Nazi Germany (1933) Anti-Aircraft Gun – 19,650 Built

With the growing use of aircraft during the First World War, many nations developed their own anti-aircraft weapons. Initially, these were mostly crude adaptations of existing weapons systems. During the interwar period, the development of dedicated anti-aircraft guns was initiated by many armies. Germany, while still under a ban on developing new weapons, would create the 8.8 cm Flak 18 anti-aircraft gun. The gun, while originally designed for the anti-aircraft role, was shown to possess excellent anti-tank firepower. This gun would see action for the first time during the Spanish Civil War (1936-1939) and would continue serving with the Germans up to the end of World War II.

World War One Origins

Prior to the Great War, aircraft first saw service in military operations during the Italian occupation of Libya in 1911. These were used in limited numbers, mostly for reconnaissance, but also for conducting primitive bombing raids. During the First World War,  the mass adoption of aircraft in various roles occurred. One way to counter enemy aircraft was to employ one’s own fighter cover. Despite this, ground forces were often left exposed to enemy bombing raids or reconnaissance aircraft that could be used to identify weak spots in the defense.

To fend off airborne threats, most armies initially reused various artillery pieces, sometimes older, or even captured guns, and modified them as improvised anti-aircraft weapons. This involved employing ordinary artillery guns placed on improvised mounts that enabled them to have sufficient elevation to fire at the sky. These early attempts were crude in nature and offered little chance of actually bringing down an enemy aircraft. But, occasionally, it did happen. One of the first recorded and confirmed aircraft kills using a modified artillery piece happened in September of 1915, near the Serbian city of Vršac. Serbian artilleryman Raka Ljutovac managed to score a direct hit on a German aircraft using a captured and modified 75 mm Krupp M.1904 gun.

On the Western Front, the use of these improvised and crude contraptions generally proved ineffective. Dedicated anti-aircraft guns were needed. This was especially the case for the Germans who lacked fighter aircraft due to insufficient resources and limited production capacity. The Germans soon began developing such weapons. They noticed that the modified artillery pieces were of too small a caliber (anything smaller than 77 mm caliber was deemed insufficient) and needed much-improved velocity and range. Another necessary change was to completely reorganize the command structure, by unifying the defense and offensive air force elements, into a single organizational unit. This was implemented in late 1916. This meant that the anti-aircraft guns were to be separated from ordinary artillery units. The effect of this was that the new anti-aircraft units received more dedicated training and could be solely focused on engaging enemy aircraft.The same year, trucks armed with 8 to 8.8 cm anti-aircraft guns began to appear on the front. While these had relatively good mobility on solid ground, the conditions of the Western Front were generally unsuited for such vehicles, due to difficult terrain. With the development of better anti-aircraft gun designs, their increased weight basically prevented them from being mounted on mobile truck chassis. Instead, for mobility, these were placed on specially designed four-wheeled trailers and usually towed by a K.D.I artillery tractor.

Both Krupp and Ehrhardt (later changing their name to Rheinmetall) would develop their own 8.8 cm anti-aircraft guns, which would see extensive action in the later stages of the war. While neither design would have any major impact (besides the same caliber) on the development of the later 8.8 cm Flak, these were the first stepping stones that would ultimately lead to the creation of the famous gun years later.

Work after the War

Following the German defeat in the First World War, they were forbidden from developing many technologies, including artillery and anti-aircraft guns. To avoid this, companies like Krupp simply began cooperating with other arms manufacturers in Europe. During the 1920s, Krupp partnered with the Swedish Bofors armament manufacturer. Krupp even owned around a third of Bofors’ shares.

The Reichswehr (English: German Ground Army) only had limited anti-aircraft capabilities which relied exclusively on 7.92 mm caliber machine guns. The need for a proper and specialized anti-aircraft gun arose in the late 1920s. In September 1928, Krupp was informed that the Army wanted a new anti-aircraft gun. It had to be able to fire a 10 kg round at a muzzle velocity of 850 m/s. The gun itself would be placed on a mount with a full 360° traverse and an elevation of -3° to 85°. The mount and the gun were then placed on a cross-shaped base with four outriggers. The trailer had side outriggers that were raised during movement. The whole gun when placed on a four-wheeled bogie was to be towed at a maximum speed of 30 km/h. The total weight of the gun had to be around 9 tonnes. These requirements would be slightly changed a few years later to include new requests such as a rate of fire between 15 to 20 rounds per minute, use of high-explosive rounds with a delay fuse of up to 30 seconds, and a muzzle velocity between 800 to 900 m/s. The desired caliber of this gun was also discussed. The use of a caliber in the range of 7.5 cm was deemed to be insufficient and a waste of resources for a heavy gun. But despite this, a 7.5 cm Flak L/60 was developed, but it would not be adopted for service. The 8.8 cm caliber, which was used in the previous war, was more desirable. This caliber was set as a bare minimum, but usage of a larger caliber was allowed under the condition that the whole gun weight would not be more than 9 tonnes. The towing trailer had to reach a speed of 40 km/h (on a good road) when towed by a half-track or, in case of emergency, by larger trucks. The speed of redeployment for these guns was deemed highly important. German Army Officials were quite aware that the development of such guns could take years to complete. Due to the urgent need for such weapons, they were even ready to adopt temporary solutions.

Krupp engineers that were stationed at the Sweden Bofors company were working on a new anti-aircraft gun for some time. In 1931, Krupp engineers went back to Germany, where, under secrecy, they began designing the gun. By the end of September 1932, Krupp delivered two guns and 10 trailers. After a series of firing and driving trials, the guns proved to be more than satisfactory and, with some minor modifications, were adopted for service in 1933 under the name 8.8 cm Flugabwehrkanone 18 (anti-aircraft gun) or, more simply, Flak 18. The use of the number 18 was meant to mislead France and Great Britain that this was actually an old design, which it was in fact not. This was quite commonly used on other German-developed artillery pieces that were introduced to service during the 1930s. The same 8.8 cm gun was officially adopted when the Nazis came to power.  In 1934, Hitler denounced the Treaty of Versailles, and openly announced the rearmament of the German Armed forces.

Production

While Krupp designed the 8.8 cm FlaK 18, aside from building some 200 trailers for it, was not directly involved in the production of the actual gun. The 8.8 cm Flak 18 was quite an orthodox anti-aircraft design, but what made it different was that it could be mass-produced relatively easily, which the Germans did. Most of its components did not require any special tooling and companies that had basic production capabilities could produce these.

Some 2,313 were available by the end of 1938. In 1939, the number of guns produced was only 487, increasing to 1,131 new ones in 1940. From this point, due to the need for anti-aircraft guns, production constantly increased over the coming years. Some 1,861 examples were built in 1941, 2,822 in 1942, 4,302 in 1943, and 5,714 in 1944. Surprisingly, despite the chaotic state of the German industry, some 1,018 guns were produced during the first three months of 1945. In total,  19,650 8.8 cm Flak guns were built.

Of course, like many other German production numbers, there are some differences between sources. The previously mentioned numbers are according to T.L. Jentz and H.L. Doyle (Dreaded Threat: The 8.8 cm FlaK 18/36/47 in the Anti-Tank role). Author A. Radić (Arsenal 51) mentions that, by the end of 1944, 16,227 such guns were built. A. Lüdeke (Waffentechnik Im Zweiten Weltkrieg) gives a number of 20,754 pieces being built.

Year	Number produced
1932	2 prototypes
1938	2,313 (total produced at that point)
1939	487
1940	1,131
1941	1.861
1942	2.822
1943	4,302
1944	5,714
1945	1,018
Total	19,650

Design

The gun 

The 8.8 cm Flak 18 used a single tube barrel that was covered in a metal jacket. The barrel itself was some 4.664 meters (L/56) long. The gun recuperator was placed above the barrel, while the recoil cylinders were placed under the barrel. During firing, the longest recoil stroke was 1,050 mm, while the shortest was 700 mm.

The 8.8 cm gun had a horizontal sliding breechblock which was semi-automatic. It meant that, after each shot, the breach opened on its own and ejected the shell casing, enabling the crew to immediately load another round. This was achieved by adding a spring coil, which was tensioned after firing. This provided a good rate of fire of up to 15 rounds per minute when engaging ground targets and up to 20 rounds per minute for aerial targets. If needed, the semi-automatic system could be disengaged and the whole loading and extracting of rounds done manually. While some guns were provided with a rammer to help during loading the gun, it was sometimes removed by the crew.

For the anti-tank role, the 8.8 cm Flak was provided with a Zielfernrohr 20 direct telescopic sight. It had 4x magnification and a 17.5° field of view. This meant a 308 m wide view at 1 km. With a muzzle velocity of 840 m/s, the maximum firing range against ground targets was 15.2 km. The maximum altitude range was 10.9 km, but the maximum effective range was around 8 km.The dimensions of this gun during towing were a length of 7.7 m, width of 2.3 m, and height of 2.4 meters. When stationary, the height was 2.1 m, while the length was 5.8 meters. Weight in firing position, it weighed 5,150 kg, while the total weight of the gun with the carriage was 7,450 kg. Due to some differences in numbers between sources, the previously mentioned 8.8 cm Flak performance is based on T.L. Jentz and H.L. Doyle (Panzer Tracts Dreaded Threat The 8.8 cm FlaK 18/36/47 in the Anti-Tank role).

The Gun Controls

The gun elevation and traverse were controlled by using two handwheels located on the right side. The traverse handwheel had an option to be rotated at low or high speed, depending on the need. The lower speed was used for more precise aiming at the targets. The speed gear was changed by a simple lever located at the handwheel. To make a full circle, the traverse operator, at a high-speed setting. needed to turn the handwheel 100 times. while on the lower gear, it was 200 times. With one full circle of the handwheel, the gun was rotated by 3.6° at high speed and 1.8° at low speed.

Next to it was the handwheel for elevation. The handwheel was connected by a series of gears to the elevation pinion. This then moved the elevation rack which, in turn, lowered and raised the gun barrel. Like the traverse handwheel, it also had options for lower and higher rotation speed, which could be selected by using a lever. During transport, in order to prevent potential damage to the gun elevating mechanism, a locking system was equipped. In order to change position from 0° to 85°, at high speed, 42.5 turns of the handwheel were needed. One turn of the wheel at high speed changed the elevation by 2°. At lower speed, 85 times turns of the handwheel were needed. Each turn gave a change of 1°.

Sometimes, in the sources, it is mentioned that the traverse was actually 720°. This is not a mistake. When the gun was used in a static mount, it would be connected with wires to a fire control system. In order to avoid damaging these wires, the guns were allowed to only make two full rotations in either direction. The traverse operator had a small indicator that informed him when two full rotations were made.

The 8.8 cm fuze setter is located on the left side of the gun. Two rounds could be placed for their time fuse settings. These were usually done manually but the gun controls could also be connected to an external control system.

The Kommandogerat 36

The fire control system Kommandogerat 36 (Stereoscopic Director 36) was an important device when using the 8.8 cm guns in an anti-aircraft role. This piece of equipment actually is a combination of a stereoscopic rangefinder and a director. It uses a 4-meter-long, stereoscopic rangefinder. It has a magnification of 12 to 14x with a reading case ranging from 500 to 50,000 meters. When the unit was being transported, the stereoscopic rangefinder would be disengaged and placed in a long wooden box. If for some reason the Stereoscopic Director 36 was not available or not working, a smaller auxiliary Stereoscopic Director 35 could be used instead.

The 8.8 cm guns were usually used in a square formation consisting of four guns.  Inside this squire was a command post, which would usually have additional range-finding equipment and instruments. These four gun’s positions were also connected to the battery unit command.

Mount

The mount which held the gun barrel itself consisted of a cradle and trunnions. The cradle had a rectangular shape. On its sides, two trunnions were welded. In order to provide stability for the gun barrel, two spring-shaped equilibrations were connected to the cradle using a simple clevis fastener.

Carriage

Given its size, the gun used a large cross-shaped platform. It consisted of the central part, where the base for the mount was located, along with four outriggers. The front and the rear outriggers were fixed to the central base. The gun barrel travel lock was placed on the front outrigger. The side outriggers could be lowered during firing. These were held in place by pins and small chains which were connected to the gun mount. To provide better stability during firing the gun, the crew could dig in the steel pegs located on each of the side outriggers. This cross-shaped platform, besides holding the mount for the main gun, also served to provide storage for various equipment, like the electrical wiring. Lastly, on the bottom of each outrigger, there were four round-shaped leveling jacks. This helped prevent the gun from digging in into the ground, distributing the weight evenly, and to help keep the gun level on uneven ground.

Bogies

The entire gun assembly was moved using a two-wheeled dolly, designated as Sonderanhanger 201. The front part consisted of a dolly with single wheels, while the rear dolly consisted of a pair of wheels per side on a single axle. Another difference between these two was that the front dolly had 7, and the rear had 11 transverse leaf springs. The wheel diameter was the same for the two, at 910 mm. These were also provided with air brakes. While these units were supposed to be removed during firing, the crew would often not remove them, as it was easier to move the gun quickly if needed. This was only possible when engaging targets at low gun elevations. Aerial targets could not be engaged this way, as the recoil would break the axles. The front and rear outriggers would be raised from the ground by using a winch with chains located on the dollies. When raised to a sufficient height, the outriggers would be held in place by dolly’s hooks. These were connected with a round pin, located inside of each of the outriggers.

Later, a new improved Sonderanhanger 202 model was introduced (used on the Flak 36 version). On this redesigned version, the two towing units were redesigned to be similar to each other. This was done to ease production but also so the gun could be towed in either direction when needed. While, initially, the dolly was equipped with one set of two wheels and the trailer with two pairs, the new model adopted a doubled-wheeled dolly instead.

Protection

Initially, the 8.8 cm Flak guns were not provided with an armored shield for crew protection. Given its long-range and its intended role as an anti-aircraft gun, this was deemed unnecessary in its early development. Following the successful campaign in the West against France and its Allies in 1940, the Commanding General of the I. Flakkorp requested that all 8.8 cm Flak guns that would be used at on the frontline receive a protective shield. During 1941, most 8.8 cm Flaks that were used on the frontline were supplied with a 1.75 meter high and 1.95 meters wide frontal armored shield. Two smaller armored panels (7.5 cm wide at top and 56 cm at bottom) were placed on the sides. The frontal plate was 10 mm thick, while the two side plates were 6 mm thick. The recuperator cylinders were also protected with an armored cover. The total weight of the 8.8 cm Flak armored plates was 474 kg. On the right side of the large gun shield, there was a hatch that would be closed during the engagement of ground targets. In this case, the gunner would use telescopic sight through the visor port. During engagement of air targets, this hatch was open.

Ammunition

The 88 mm FlaK could use a series of different rounds. The 8.8 cm Sprgr. Patr. was a 9.4 kg heavy high-explosive round with a 30-second time fuze. It could be used against both anti-aircraft and ground targets. When used in the anti-aircraft role, the time fuze was added. The 8.8 Sprgr. Az. was a high-explosive round that had a contact fuze. In 1944 the Germans introduced a slightly improved model that tested the idea of using control fragmentation, which was unsuccessful. The 8.8 Sch. Sprgr. Patr. and br. Sch. Gr. Patr. were shrapnel rounds.

The 8.8 cm Pzgr Patr was a 9.5 kg standard anti-tank round. With a velocity of 810 m/s, it could penetrate 95 mm of 30° angled armor at 1 km. At 2 km at the same angle, it could pierce 72 mm of armor. The 8.8 cm Pzgr. Patr. 40 was a tungsten-cored anti-tank round. The 8.8 cm H1 Gr. Patr. 39 Flak was a 7.2 kg heavy hollow charge anti-tank round. At a 1 kg range, it was able to penetrate 165 mm of armor. The 8.8 cm ammunition was usually stored in wooden or metal containers.

Crew

The 88 mm Flak had a crew of 11 men. These included a commander, two gun operators, two fuze setter operators, a loader, four ammunition assistants, and the driver of the towing vehicle. Guns that were used on a static mount usually had a smaller crew. The two gun operators were positioned to the right of the gun. Each of them was responsible for operating a hand wheel, one for elevation and one for the traverse. The front operator was responsible for traverse and the one behind him for elevation. The front traverse operator was also responsible for using the weapon gun sight for targeting the enemy. On the left side of the gun were the two fuse operators. The loader with the ammunition assistants was placed behind the gun. A well-experienced crew needed 2 to 2 and a half minutes to prepare the gun for firing. The time to put the gun into the traveling position was 3.5 minutes. The 8.8 cm gun was usually towed by an Sd.Kfz. 7 half-track or a heavy-duty six-wheel truck.

Flak 36 and 37

While the Flak 18 was deemed a good design, there was room for improvement. The gun itself did not need much improvement. The gun platform, on the other hand, was slightly modified to provide better stability during firing and to make it easier to produce. The base of the gun mount was changed from an octagonal to a more simple square shape. The previously mentioned  Sonderanhanger 202 was used on this model.

Due to the high rate of fire, anti-aircraft guns frequently had to receive new barrels, as these were quickly worn out. To facilitate quick replacement, the Germans introduced a new three-part barrel. It consists of a chamber portion, a center portion, and the muzzle section. While it made the replacement of worn-out parts easier, it also allowed these components to be built with different metals. Besides this, the overall performance of the Flak 18 and Flak 36 was the same. The Flak 36 was officially adopted on the 8th of February 1939.

As the Germans introduced the new Flak 41, due to production delays, some of the guns were merged with the mount of a Flak 36. A very limited production run was made of the 8.8 cm Flak 36/42, which entered service in 1942.

In 1942, the improved 88 mm Flak 37 entered mass production according to T.L. Jentz and H.L. Doyle. On the other hand J. Ledwoch (8.8 cm Flak 18/36/37 Vol.1 Wydawnictwo Militaria 155) state that the Flak 37 was introduced to service way back in 1937. Visually, it was the same as the previous Flak 36 model. The difference was that this model was intended to have better anti-aircraft performance, having specially designed directional dials. The original gunner dials were replaced with the “follow-the-pointer” system. It consists of two sets of dials that are placed on the right side of the gun. These received information about the enemy targets from a remote central fire direction post connected electrically. This way, the gun operator only had to make slight adjustments, such as elevation, and fire the gun.

The necessary information about the enemy targets was provided by a Funkmessgerate ( Predictor) which was essentially a mechanical analog computer. Once the enemy aircraft were spotted, their estimated speed and direction were inserted into this computer which would then calculate the precise position and elevation. This information would be sent to any linked anti-aircraft batteries by a wire connection. One set of the dials would then show the crew the necessary changes that need to be done to the elevation and direction of the enemy approach. The crew then had to manually position the gun elevation and direction until the second dials indicators matched the first one. The funkmessgerate computer also provided correct fuse time settings. In principle, this system eased the aiming task of the crew and at the same time improved accuracy. When used in this manner the Flak 37 could not be used for an anti-tank role.

The last change to this series was the reintroduction of a two-piece barrel design. Besides these improvements, the overall performance was the same as with the previous models. From March 1943 only the Flak 37 would be produced, completely replacing the older models.

Organization 

German air defense was solely the responsibility of the Luftwaffe, with the majority of 8.8 cm guns being allocated to them. The German Army and Navy also possessed some anti-aircraft units, but these were used in quite limited numbers. The largest units were the Flak Korps (Anti-aircraft corps). It consisted of two to four Flak Divisionen (Anti-aircraft divisions). These divisions, depending on the need, were either used as mobile forces or for static defense. These were further divided into Bigaden (brigades ) which consisted of two or more Regimenter (Regiments). Regiments in turn were divided into four to six Abteilunge (Battalion). Battalion strength was eight 8.8 cm guns with 18 smaller 2 cm guns. To complicate things a bit more, each Battalion could be divided into four groups: Leichte (Light, equipped with calibers such as 2 cm or 3.7 cm), Gemischte (mixed light and heavy), Schwere (Heavy equip with a caliber greater than 88 mm) and Scheinwerfer  (Searchlight).

Mobile War

Initially, operations and crew training was carried out by the Reichswehr. They were organized into the so-called Fahrabteilung (Training Battalion) to hide their intended role. By 1935, the German Army underwent a huge reorganization, one aspect of which was changing its name to the Wehrmacht. In regard to the anti-aircraft protection, it was now solely the responsibility of the Luftwaffe. For this reason, almost all available 8.8 cm guns were reallocated to Luftwaffe control. Only around eight Flak Battalions which were armed with 2 cm anti-aircraft guns were left under direct Army control.

In Spain

When the Spanish Civil War broke out in 1936, Francisco Franco, leader of the Nationalists, sent a plea to Adolf Hitler for German military equipment aid. To make matters worse for Franco, nearly all his loyal forces were stationed in Africa. As the Republicans controlled the Spanish navy, Franco could not move his troops back to Spain safely. So he was forced to seek foreign aid. Hitler was keen on helping Franco, seeing Spain as a potential ally, and agreed to provide assistance. At the end of July 1936, 6 He 51 and 20 Ju 57 aircraft were transported to Spain under secrecy. These would serve as the basis for the air force of the German Condor Legion which operated in Spain during this war. The German ground forces operating in Spain were supplied with a number of 8.8 cm guns.

These arrived in early November 1936 and were used to form the F/88 anti-aircraft battalion. This unit consisted of four heavy and two light batteries. Starting from March 1937 these were allocated to protect various defense points at Burgos and Vittoria. In March 1938, the 8.8 cm guns from the 6th battery dueled with an enemy 76.2 cm anti-aircraft gun which were manned by French volunteers from the International Brigades. While the 8.8 cm guns were mainly employed against ground targets they still had a chance to fire at air targets. For example, while defending the La Cenia airfield, the 8.8 cm guns from the 6th battery prevented the Republican bombing attack by damaging at least two SB-2 bombers on the 10th of June 1938. Three days later one SB-2 was shot down by an 8.8 cm gun. In early August another SB-2 was shot down by the same unit. The performance of the 8.8 cm gun during the war in Spain was deemed satisfying. It was excellent in ground operations, possessing good range and firepower.

During the Second World War

Prior to the war, the 8.8 m guns could be often seen on many military parades, exercises, and ceremonies. The first ‘combat’ use of the 8.8 cm Flak in German use was during the occupation of the Sudetenland in 1938. The entire operation was carried out peacefully and the 8.8 cm gun did not have to fire in anger.

The Polish campaign saw little use of the 8.8 cm guns. The main reason for this was that the Polish Air Force was mostly destroyed in the first few days of combat. They were mainly used against ground targets. In one example, the 8.8 cm guns from the 22nd Flak Regiment tried to prevent a Polish counter-attack at Ilza. The battery would be overrun while the crew tried to defend themselves, losing three guns in the process. The 8.8 cm Flak gun also saw service during the battles for Warsaw and Kutno.

The 8.8 cm followed the Germans in their occupation of Denmark and Norway. One of the key objectives in Norway was the capture of a number of airfields. Once captured, the Germans rushed in Flak guns including the 8.8 cm, to defend these as they were crucial for the rather short-ranged German bombers. On the 12th of April 1940, the British Air Force launched two (83 strong in total) bombing raids at the German ships which were anchored at the Stavanger harbor. Thanks to the Flak and fighter support, six Hampden and three Wellington bombers were shot down.

Following the conclusion of the Polish campaign, the Germans began increasing the numbers of the motorized Flak units. Some 32 Flak Batteries were available which the Germans used to form the 1st and 2nd Flak Corps. 1st Corps would be allocated to the Panzergruppe Kleist, while the second was allocated to the 4th and 6th Army. The Luftwaffe, as in Poland (September 1939), quickly gained air superiority over the Allied Air Forces. Despite this, there was still opportunity for the 8.8 cm guns to fire at air targets.  During the period from the 10th to 26th May 1940, the following successes were made against enemy aircraft by flak units that were part of the XIX Armee Corps: the 83rd Flak Battalion brought down some 54, 92nd Flak Battalion 44, 71th Flak Battalion 24, the 91st Flak Battalion 8, 36th Flak Regiment 26, 18th Flak Regiment 27, and 38th Flak Regiment 23 aircraft. During the notorious German crossing near Sedan, a combined Allied air force tried to dislodge them. The strong Flak presence together with air fighter cover, lead to the Allies losing 90 aircraft in the process.

Following the Western Campaign, the 8.8 cm guns would see extensive service through the war. Ironically they would be more often employed against enemy armor than in the original role. Given the extensive Allied bombing raids, more and more 8.8 cm would be allocated to domestic anti-aircraft defense. One major use of 8.8 cm Flak was during the German evacuation of Sicily, by providing necessary air cover for the retreating Axis soldiers and materiel to the Italian mainland.

In the occupied Balkans, the 8.8 cm Flak was a rare sight until late 1943 and early 1944. The ever-increasing Allied bombing raids forced the Germans to reinforce their positions with a number of anti-aircraft guns, including the 8.8 cm Flak. Some 40 8.8 cm Flak guns were used to protect German-held Belgrade, the capital of Yugoslavia. Most would be lost after a successful liberation operation conducted by the Red Army supported by Yugoslav Partisans. The 8.8 cm Flak guns were also used in static emplacements defending the Adriatic coast at several key locations from 1943 on. One of the last such batteries to surrender to the Yugoslav Partisans was the one stationed in Pula, which had twelve 8.8 cm guns. It continued to resist the Partisans until the 8th of May, 1945.

Defense of the Fatherland

While the 8.8 cm Flaks would see service supporting the advancing German forces, the majority of them would actually be used as static anti-aircraft emplacements. For example, during the production period of October 1943 to November 1944, around 61% of the 8.8 cm Flak guns produced were intended for static defense. Additionally, of 1,644 batteries that were equipped with this gun, only 225 were fully motorized, with an additional 31 batteries that were only partially motorized (start of September 1944).

When the war broke out with Poland, the Luftwaffe anti-aircraft units had at their disposal some 657 anti-aircraft guns of various calibers. The majority were the 8.8 cm with smaller quantities of the larger 10.5 cm and even some captured Czezh 8.35 anti-aircraft guns. An additional 12 Flak Companies equipped with the 8.8 cm guns were given to the navy for the protection of a number of important harbors. The remaining guns were used to protect vital cities like Berlin and Hamburg. The important Ruhr industry center was also heavily defended.

One of the first enemy aircraft shot down over German skies were British Wellington bombers. This occurred on the 4th of September 1939 when one or two enemy bombers were brought down by heavy Flak fire. These intended to bomb vital German naval ports. In early October 1939, in Strasbourg, a French Potez 637 was shot down by the 84th Flak Regiments 8.8 cm guns. One Amiot 143 and a Whitley aircraft were shot down in Germany in mid-October. During December 1939 British launched two bombing raids intended to inflict damage on German ports. Both raids failed with the British losing some 17 out of 36 Wellington bombers.

After Germany’s victory over the Western Allies in June, the Germans began forming the first Flak defense line in occupied territories and coastlines. These  were not only equipped with German guns but also with those captured from enemy forces.

Due to the poor results of their daylight bombing raids, the British began to employ night raids. These initially were quite unsuccessful with minimal damage to Germany’s infrastructure and industry. The Flak defense of Germany was also quite unprepared for night raids, unable to spot enemy bombers at night. The situation changed only in 1940 with the introduction of ground-operated radar. Thanks to this, the first few months of 1941 saw German Flak units bring down 115 enemy aircraft.

In 1942 the British military top made a decision to begin the mass bombing of German cities. The aim was to “de-house” (or kill) workers, damage infrastructure to make urban industrial areas unusable, and try and cause a moral collapse as was the case in 1918. Implementation of this tactic was initially slow due to an insufficient number of bombers. In addition, vital targets in occupied Europe were also to be bombed. In May 1942, the British launched a force that consisted of over 1,000 aircraft causing huge damage to Germany, killing 486 and injuring over 55,000 people.

In 1943 several huge events happened. The German defeats in East and North Africa led to huge material and manpower losses, while the Allies were preparing to launch massive bombing raids mainly intended to cripple Germany’s production capabilities. In response, the Germans began increasing their number of Flak units. At the start of 1943, there were some 659 heavy Flak batteries, which were increased to  1,089 by June the same year. Due to a lack of manpower, the Germans began mobilizing their civilians regardless of their age or sex. For example, in 1943 there were some 116,000 young women who were employed in various roles, even operating the guns. Near the end of the war, it was common to see all-female crews operating Flak batteries. In addition in 1944 some 38,000 young boys were also employed in this manner. Ironically, while all German military branches lacked equipment, the anti-aircraft branch had spare equipment and guns, but lacked the manpower to operate them. To resolve this, foreign Volunteers and even Soviet prisoners of war were pressed into service. The downside was the general lack of training, which greatly affected their performance.

In the first few months of 1944, the Allied 8th and 15th Air Forces lost some 315 bombers with 10,573 damaged, all attributed to the heavy Flak. In 1944 (date unspecified in the source) during an attack on the heavily defended Leuna synthetic oil refinery, some 59 Allied bombers were brought down by the heavy Flak guns. By 1944 the number of heavy anti-aircraft guns that were intended for the defense of Germany reached 7,941. By April 1945 the Flak guns managed to shoot down 1,345 British bombers. The American 8th lost 1,798, while the 15th Air Force lost 1,046 bombers due to German Flak defence by the end of the war.

The last action of the 8.8 cm Flak guns was during the defense of the German capital of Berlin. Due to most being placed in fixed positions, they could not be evacuated and most would be destroyed by their own crews to prevent capture. Despite the losses suffered during the war, in February 1945, there were still some 8,769 8.8 cm Flak guns available for service.

Effectiveness of the 8.8 cm Guns in Anti-aircraft Role

Regarding the effectiveness of the 8.8 cm anti-aircraft guns with the necessary number of rounds needed to bring down enemy aircraft. Author E.B. Westermann (Flak German Anti-Aircraft Defenses 1914-1945) gives us a good example and comparison between three main German anti-aircraft guns. The largest 12.8 cm Flak on average fired some 3,000 rounds to take down an enemy aircraft. The 10.5 cm gun needed 6,000 and the 8.8 cm 15,000 rounds (some sources mentioned 16,000). This seems at first glance like a huge waste of available resources, but is it right to conclude that?

According to an Allied war document dated from early 1945, they mentioned a few interesting facts about German flak defense. According to them, in 1943 some 33% of bombers destroyed by Germany were accredited to heavy Flak gunfire. In addition, 66% of damage sustained by their aircraft was also caused by the heavy Flak fire. In the summer of 1944, this number increased. The majority (some 66%) shot down enemy bombers were accredited to the heavy Flaks. And of 13,000 damaged bombers some 98% were estimated to be caused by the Flaks. Here it is important to note that by this time, Luftwaffe fighters lacked the ability to attack bomber formations en mass. Therefore this increase of aircraft shot down by the Flaks may be explained by this.

In addition, we must also take into account two other functions that these guns had which are often overlooked. They did not necessarily need to bring down enemy bombers. It was enough to force the enemy fly at higher altitudes to avoid losses. This in turn led to a huge loss of accuracy for the bombers. Secondly, the enemy bombers were often forced to break formation when sustaining heavy Flak fire, which left them exposed to German fighters. The shrapnel from the Flak rounds could not always directly bring down a bomber, but it could cause sufficient damage (fuel leaks for example) that the aircraft, later on, had to make an emergency landing, even in enemy territory. The damaged aircraft that made it back to their bases could spend considerable time awaiting repairs. Lastly, the Flak fire could incapacitate, wound or even kill bomber crews. Thus there was a huge psychological effect on enemy bomber crews. B-17 gunner Sgt W. J. Howard from the 100th Bomb Group recalled his experience with the German Flak. “All the missions scared me to death. Whether you had fighters or not you still had to fly through the flak. Flak was what really got you thinking, but I found a way to suck it up and go on.”

Hitler was quite impressed with the 8.8 cm performance. On the 28th of August 1942, he stated:  “The best flak gun is the 8.8 cm. The 10.5 has the disadvantage that it consumes too much ammunition, and the barrel does not hold up very long. The Reich Marshall Göring continually wants to build the 12.8 into the flak program. This double-barreled 12.8 cm has a fantastic appearance. If one examines the 8.8 from a technician’s perspective, it is to be sure the most beautiful weapon yet fashioned, with the exception of the 12.8 cm”.

Despite the best German efforts, the Flak’s effectiveness greatly degraded by late 1944. The reason for this was the shortage of properly trained crews. At the start of the war, the Germans paid great attention to crew training, which lasted several months. As the Flak guns were needed on the front, less experienced and trained personnel had to be used instead. In the later stages of the war, these crews received only a few weeks of training, which was insufficient for the job they had to perform. Lastly, Allied bombing raids eventually took their toll on German industry, greatly reducing the production of ammunition, which was one of the main reasons why the anti-aircraft defense of Germany ultimately failed. Of course, a proper analysis and conclusion could not be easily made and would require more extensive research, a wholly different topic on its own.

Self-Propelled Versions

When used as anti-aircraft weapons, the 8.8 cm guns were in most cases used as static defense points. Despite this, the Germans made several attempts to increase their mobility by placing the 8.8 cm guns on various chassis. One of the first attempts was by mounting the 8.8 cm gun on a VOMAG 6×6 truck chassis. The small number built was given to the 42nd Flak Regiment which operated them up to the end of the war.

The truck chassis offered great mobility on good roads, but their off-road handling was highly problematic. So Germans used half-tracks and full-track chassis.  Smaller numbers of Sd. Kfz 9 armed with the 8.8 cm gun were built. Attempts to build a full-track vehicle were made but never went beyond a prototype stage. The 8.8 cm Flak auf Sonderfahrgestell was a project where an 8.8cm gun was mounted on a fully tracked chassis with a folding wall, but only one vehicle would be built.  There are some photographs of Panzer IV modified with this gun, and while not much is known about them they appear to be a field conversion, rather than dedicated design vehicles. There were even proposals to mount an 8.8 cm gun on a Panther tank chassis, but nothing would come from it in the end.

Usage after the war

With the defeat of Germany during the Second World War, the 8.8 cm Flak guns found usage in a number of other armies. Some of these were Spain, Portugal, Albania, and Yugoslavia. By the end of the 1950s, the Yugoslavian People’s Army had slightly less than 170 8.8 cm guns in its inventory. These were, besides their original anti-aircraft role, used to arm navy ships and were later placed around the Adriatic coast. A number of these guns would be captured and used by various warring parties during the Yugoslav civil wars of the 1990s. Interestingly, the Serbian forces removed the 8.8 cm barrel on two guns and replaced them with two pairs of 262 mm Orkan rocket launcher tubes. The last four operational examples were finally removed from service from the Serbian and Montenegrin Army in 2004.

Conclusion

The 8.8 cm Flak was an extraordinary weapon that provided the German Army with much-needed firepower during the early stages of the war. The design as a whole was nothing special, but it had a great benefit in that it could be built relatively cheaply and in great numbers. That was probably its greatest success, being available in huge numbers compared to similar weapons of other nations.

Its performance in the anti-aircraft role was deemed satisfying, but still stronger models would be employed to supplement its firepower. The 8.8 cm anti-air gun’s effectiveness was greatly degraded toward the end of the war, which was caused not by the gun design itself but other external forces. These being mainly the lack of properly trained crews and shortages of ammunition.

8.8 cm Flak 18 Specifications:
Crew: 11	(Commander, two gun operators, two fuze setter operators, loader, four ammunition assistants, and the driver)
Weight in firing position:	5150 kg
Total weight:	7450 kg.
Dimensions in towing position:	Length 7.7  m, Width 2.2 m, Height 2.4 m,
Dimensions in deployed position:	Length 5.8  m, Height 214 m,
Primary Armament:	8.8 cm L/56 gun
Elevation:	-3° to +85°

Gallery

Credits

• Written by Marko P.
• Edited by by Ed Jackson & Henry H.
• Illustrations by David B.

Sources

• J. Norris  (2002) 8.8 cm FlaK 16/36/37/ 41 and PaK 43 1936-45 Osprey Publishing
• D. Nijboer (2019) German Flak Defences Vs. Allied Heavy Bombers 1942-45, Osprey Publishing
• T.L. Jentz and H.L. Doyle  Panzer Tracts No. Dreaded Threat The 8.8 cm FlaK 18/36/41 in the Anti-Tank role
•  T.L. Jentz and H.L. Doyle (2014) Panzer Tracts No. 22-5 Gepanzerter 8t Zugkraftwagen and Sfl.Flak
• W. Muller (1998) The 8.8 cm FLAK In The First and Second World Wars, Schiffer Military
• E. D. Westermann (2001) Flak, German Anti-Aircraft Defense 1914-1945, University Press of Kansas.
• German 88-mm AntiAircraft Gun Materiel (29th June 1943) War Department Technical Manual
• T. Anderson (2018) History of Panzerwaffe Volume 2 1942-45, Osprey publishing
• T. Anderson (2017) History of Panzerjager Volume 1 1939-42, Osprey publishing
• S. Zaloga (2011) Armored Attack 1944, Stackpole book
• W. Fowler (2002) France, Holland and Belgium 1940, Allan Publishing
• 1ATB in France 1939-40, Military Modeling Vol.44 (2014) AFV Special
• N, Szamveber (2013) Days of Battle Armored Operation North of the River Danube, Hungary 1944-45
• A. Radić (2011) Arsenal 51 and 52
• While A. Lüdeke, Waffentechnik im Zweiten Weltkrieg, Parragon
•  J. Ledwoch 8.8 cm Flak 18/36/37 Vol.1 Wydawnictwo Militaria 155
• S. H. Newton (2002)  Kursk The German View, Da Capo Press
• W. Howler (2002 France, Belgium and Holland 1940, Ian Allan
• J. S. Corum (2021) Norway 1940 The Luftwaffe’s Scandinavian Blitzkrieg, Osprey Publishing
• https://uofa.ru/en/zenitnoe-orudie-88-vermaht-strashnaya-vosemdesyat-vosmaya/

Germany (1937)Rocket Powered Aircraft – 1 Prototype Built

Prior to, and during the war, the German aviation industry developed a series of operational and prototype aircraft designs. Among the leading new technologies, rocket-powered aircraft were being developed. The concept was initially tested prior to the war on a smaller scale, including limited theoretical tests and prototyping. But further development would lead to the creation of the first rocket-powered aircraft known as the He 176. While it wasn’t accepted for service, it proved that such a concept was feasible and set the stage for the later Me 163 rocket-powered aircraft.

History of Rocket Engine Development in Germany

Following the end of the Great War, Germany was forbidden to have an Air Force. This also included the development of aircraft designs, though this did not stop the Germans from experimenting with new aviation technology. One such new technology was rocket propulsion. One of the first such flights using rocket propulsion occurred in June of 1928, when aviation enthusiast Fritz Stramer took to the sky his rocket-powered glider. Another pioneer in rocket-powered flight occurred at the end of September 1929. A pilot named Fritz von Opel managed to take to the sky in his rocket-powered glider, named Ente (Duck). Von Opel was assisted by another prominent aircraft designer Alexander Martin Lippisch. While technically speaking these were not real rocket-powered flights, given that these gliders did not take to the sky using purely the rocket engine but were towed to altitude. Nevertheless, these flights showed that flight using rocket engines was possible.

Over the following years, Lippisch became quite interested in rocket technology and would join the Deutsche Forschungsinstitut DFS, where he worked as an engineer. There, he developed a series of new glider designs, like the DFS 40. This work would eventually lead to the creation of the Me 163 rocket-powered aircraft. The Junkers Aircraft company also was interested in rocket development as they built and tested rocket take-off boosters. One such engine was ground tested in 1936.Another stepping stone in rocketry research was the work of Wernher von Braun. In 1932 and 1934 von Braun managed to successfully launch two rockets using liquid-fuel rocket engines. In 1935 he managed to come into contact with Dr. Ernst Heinkel 1935. After von Braun presented his work, Dr. Ernst was highly impressed and promised to provide von Braun with any assistance in his work. For this, he appointed a young and energetic aircraft engineer named Walter Wenzelunzel to assist von Braun. In order to properly test the installation of rocket engines in aircraft designs, a special test center was established at Kummersdorf in 1936.

Dr. Ernst supplied this research team with a few He 112 airframes. The first He 112 was used for ground testing. For this reason, its fuselage was retained while its wings and the original engine were removed. The rocket engine, which ran on a combination of liquid oxygen and alcohol, would be placed in the rear of the fuselage, with the engine nozzle being placed just beneath the tail unit. Von Braun’s team installed the oxygen tanks in front of the cockpit, with the alcohol tank behind the pilot seat. The engine (the sources do not specify its precise designation) could provide a thrust of 1,000 kg (2,200 lb) with an endurance of 30 seconds. During the testing the engine exploded, destroying the aircraft in the process.Despite this setback, the project went on. By this time, German Army Officials were becoming interested in the project. In order to maintain its secrecy, von Braun and his team were instructed to find a remote auxiliary airfield where these tests could continue to be conducted away from prying eyes. The team, wanting to be close to Berlin, chose a small field at Neuhardenberg, which was covered on most sides by dense forest. Temporary housing, cabins, and tents were quickly set up in 1937 and the work could finally go on.

In 1937 von Braun began close cooperation with another enthusiast of rocket engine development, Helmuth Walter. This cooperation was partly initiated by the German Air Ministry (Reichsluftfahrtministerium RLM) who intended to use the rocket engines for other proposals, like assistance during take-offs. Walter was a young scientist who was highly interested in rocket propulsion. He managed to obtain military funding, which greatly helped in his work. In 1936 he used a Heinkel He 72 to test this engine. In 1937, he even managed to get the attention of the RLM. The RLM formed a Special Propulsion System department (Sondertriebwerke) with the aim of experimenting with rocket engines in the aircraft industry. While this department was mainly focused on developing rocket engines for short take-off assistance, Walter wanted more than that. He intended to develop a strong rocket engine that could replace the standard piston engines of the day. Walter managed to develop such an engine, named Walter TP-1, which was fueled by the so-called ‘T-Stoff’ (hydrogen peroxide) and ‘Z-Stoff’ (water solution of either calcium or sodium permanganate).

Von Braun requested another aircraft which Henkel provided, this was the He 112 V8 (during these trials it received a slightly changed designation V8/U). The test pilot Erich Warsitz managed to take it to the sky using the aircraft’s original piston engine. Warsitz was a crucial pilot for the German early rocket and jet engine development, being heavily involved in testing and helping with the overall design of both the He 176 and He 178. At about 450 meters Warsitz activated the rocket engine, and during the 30 seconds of the engine burn phase, a speed of nearly 400 km/h (or 460 km/h (286 mph) depending on the source) was reached. Due to the dangerous leakage of the engine, the flight had to be aborted, but otherwise, the flight has deemed a success. This He 112 V8 would be returned to Heinkel, but two more aircraft (H7/U and A-03) would be donated to the rocket research program.

After this flight, all further tests were conducted using the Walter TP-1 rocket engine. In contrast to the von Braun engine which used alcohol and liquid oxygen as fuel, Walter’s own engine used hydrogen-peroxide and calcium permanganate as a catalyst. This engine was deemed safer too, which is somewhat ironic given the corrosive and volatile fuel. To avoid accidentally coming into contact with the Walter engine fuel, the pilot had to wear a highly protective suit. If exposed to the corrosive fuel, it caused disintegration without actually burning.More tests were conducted at this location until the end of 1937, when the research was to be moved to Peenemunde. Due to some delays, the tests on the He 112 continued on from April 1938.

Heinkel’s First Rocket-Powered Aircraft

Following the series of tests on the He 112, some officials from the RLM began showing great interest in the prospect of using a rocket-powered aircraft interceptor. It was originally hoped that this aircraft would be capable of vertical, or nearly vertical take-off. When sufficient altitude was reached, the aircraft was then to make a swift dive on its target, firing a volley of its full weapon load. After this attack run, it was simply to glide away once it was out of fuel, to its base of operation.

The work on the project was conducted under a veil of secrecy and began in 1936 at the Heinkel Rostock-Marienehe work. The following year the first drawings of the He 176 V1 (derived from “Versuchsmuster 1” meaning “Experimental Model”) were completed by Hans Regner. Interestingly the designers set a huge task in front of them, by actually trying to reach a blistering speed of 1000 km/h (620 mp/h). An astonishing and difficult feat to achieve with such a novelty design. This set a number of challenges that had to be overcome. One of them was a proper wing design able to withstand the pressure of such high speed. For this reason, it had to be designed to be flat, at only 90 millimeters thick, with very sharp leading edges. This in turn caused further problems, as this design would cause the aircraft to stall at low speeds. In addition, the installation of wing fuel tanks would be difficult.

In order to make the whole design smaller and thus save weight, the pilot had to be placed in a rather unpleasant semi-recumbent position, with his legs stretched out in front and the pilot’s seat reclined. This was also done to help the pilot better cope with the extreme G-forces that he would be subjected to during the extremely high forward acceleration. The fuselage had a very small diameter of only 0.8 meters (2ft 7in) and was specially designed according to the height of the test pilot, Warsitz.

The construction of the first prototype was undertaken at the Heinkel’s aircraft works in Marienehe. Once the aircraft was completed, it was to be transported to Peenemunde. The aircraft’s testing was conducted under great secrecy and was transported there via military escort in June 1938. Just prior to the actual testing, Warsitz was informed by RLM officials that given the experimental nature of the design, and Warsitz’s valued status as an experienced test pilot, he was advised not to fly it. Warsitz, who was heavily involved in the He 176 design, protested to Air Minister (Reichsluftfahrtministerium) Ernst Udet, who gave him permission to undertake the first flight. After this was settled, there were some delays with the assembly and engine adjustment.

The initial tests were undertaken on the ground. Due to unsuitable terrain and lack of a proper towing vehicle, ground testing proved ineffective. So it was decided to use the aircraft’s own engine for these tests, which were conducted at the end of 1938. Using the He 178’s own engine on the ground presented a new problem, namely the rudder could not provide steering during take-off. As the aircraft had no propellers to generate airflow, steering the aircraft using the rudder on take-off was ineffective, thus the only way to maintain the aircraft’s heading was by using the left and right brakes on the main wheels. This was quite dangerous for the pilot and the aircraft, as an imbalanced braking force could potentially lead to an accident. The result of the initial testing showed that some changes to the overall structural design were needed. For this, the Heinkel crews spent the winter of 1939 modifying the He 178.

First Flights

During the Spring of 1939, a series of small test flights were conducted with the He 178. Somewhat unexpectedly, the Heinkel team was visited by an RLM delegation led by Udet himself. After observing the He 178 on the short flight they were quite impressed, but surprisingly for the Heinkel team, Udet forbade any more flights on it. Mostly due to fear for the pilot’s life. After some delays, Warsitz visited Udet in Berlin and filed a plea that the project should go on. Udet finally accepted this and gave a green light.

While the first official flight of the He 176 was to be conducted under the supervision of many RLM officials, feeling that something might go wrong, Erich Warsitz and Heinkel’s team (without the knowledge of Dr. Erns) decided to perform the flight in secrecy. The date for this was set on the 20th of June, 1939. After a rough take-off, the pilot managed to take the He 176 to the sky. Given the small fuel load, the flight lasted around a minute. Overall, the first test flight was deemed a success. The following day, Udet and his delegation visited the site and observed another test flight.

The Fuhrer Inspects the He 176

A couple of days later Warsitz and Heinkel’s team were informed that any further flights were forbidden. The reason was that Hitler himself became interested in the project and wanted to personally see the aircraft. The He 176 was to be transported to the Rechlin Secret Test Center and shown to many high-ranking members of the Luftwaffe. On the 3rd of July 1939, the aircraft was to be demonstrated to a large delegation including Hitler himself. First, a flight of a He 111 equipped with rocket-assisted take-off was shown to Hitler, which greatly impressed him. Another Heinkel innovative design, the He 178 jet-engine powered aircraft, was also present. While it was not yet capable of taking to the sky it was used for ground testing. Next in the line for inspection was the He 176, after a brief examination of its interior by the delegation, the stage was set for it to take to the sky. The flight initially went well, but the pilot miscalculated and shut down the engine too soon. While still at high speed, he began descending rather rapidly. After several attempts to restart the engine, he finally succeeded, just before hitting the ground. The plane took an almost vertical climb of some 50 meters before the pilot regained control and landed it safely. Hitler and his delegation were under the impression that the pilot performed this maneuver intentionally to demonstrate the aircraft’s potential. For his flight, the pilot was awarded 20,000 Reichsmarks.

The End of the Project

After this exhibit, Heinkel’s team tried to prepare the He 176 for reaching speeds up to 1,000 km/h. Structural analysis of the design, on the other hand, showed that this would not be possible. For this reason, preparation for the construction of a second prototype was underway. It was to be powered by a von Braun rocket engine, which suggested that the aircraft could be launched vertically. This was possible thanks to weight reduction efforts sufficient to enable vertical take-off.

Ultimately the whole project would be canceled. The order was given by Adolf Hilter, who insisted that designs that could not enter production in less than a year, be canceled. Despite Heinkel’s attempt to win over Udet’s support, it went nowhere and the project was officially terminated.

The He 176 V1 was disassembled and transported to the Aviation Museum in Berlin to be exhibited. Sadly it would be later on destroyed in one of many Allied bombing raids. The He 176 V2 was almost complete, but its parts were eventually scrapped. The V3 had also been under construction, but was ultimately abandoned in its early stages.

Technical Characteristics

The He 176 was designed as an all-metal, high-wing rocket-powered experimental reconnaissance aircraft. Its fuselage had a simple circular cross-section design. The wings had an asymmetrical profile and were quite thin. During take-off, there was a significant chance of the wingtips contacting the ground, due to the fuselage’s small diameter and extreme vibrations during take-off. To avoid damaging them, Heinkel engineers added a “U” shaped metal bar under each wingtip as a temporary solution. The wings were also initially to act as fuel tanks, but this feature had to be abandoned on the prototype, and fuel was instead stored behind the cockpit. The tail and rudder design was more or less conventional.

The rocket engine chosen for the He 176 was the Walter RI type. It provided thrust ranging between 45 kg to 500 kg (100 to 1,1100 lb) with an endurance of one minute. Due to the weight issues combined with a relatively weak propulsion unit, the desired speed of 1,000 km/h (620 mph) was never reached. The maximum speed reached by this aircraft differs greatly between sources. For example, D. Nešić mentioned that the maximum speed was only 345 kmh, while authors J. R. Smith and A. L. Kay quoted a figure of 700 kmh. Lastly, the test pilot himself in his own logbook mentioned that he managed to reach a speed of 800 kmh (500 mph).

The landing gear consisted of one front smaller wheel, two larger wheels 700 mm in diameter, and one more to the rear. While the front wheel was fixed the remaining three were completely retractable.

The cockpit provided the pilot with an excellent forward view and was made of plexiglass. Given the experimental nature of this aircraft, great attention was given to pilot safety. As in case of emergency, bailing out of the fast-moving and cramped aircraft was almost impossible. Heinkel engineers designed the entire cockpit section to be jettisonable. The cockpit assembly was connected to the fuselage by four locks which were equipped with small explosive charges. When the pilot was jettisoned from the fuselage his parachute would open automatically and allow him to land safely. This system was tested by using a wooden cockpit containing a dummy pilot. This trial cockpit was then taken to the sky by a He 111 and at sufficient height, it was released. The parachute opened without an issue and it landed on the ground intact. The results of the dummy pilot showed that this system was safe if the cockpit landed on soft ground.The small size of the cockpit prevented the use of a standard instrument panel, as it would severely affect the pilot’s forward visibility. Instead, the instruments were placed to the left and the right of the pilot. Interestingly, while Heinkel did not intend to arm the aircraft, RLM officials insisted that two machine gun ports be placed beside the pilot. Due to the cramped cockpit interior, the two machine guns had to be placed where the pilots’ side controls were positioned. As this would cause delays and much-needed redesign work, the Heinkel engineers simply placed machine gun ports (without the actual machine guns equipped) and kept the original control units in place. The RLM officials, when visiting the work, were told that these were just temporary measures.

The Only Photograph

Given the secretive nature of the project, RLM officials effectively gathered all films and photos for themselves. All persons involved in the project were also forbidden from taking any pictures. At the war’s end, the Soviets either destroyed or captured these and their final fate is unknown. Sometime after the war, many artists attempted to produce sketches of how the He 176 may have looked. These greatly differed from the original design, but given the lack of information and general obscurity of the He 176, this is understandable.

Conclusion

The He 176 project arose as a collaboration of several different parties. It was heavily influenced by rocket engine testing and development done by von Braun and Walter. Heinkel Flugzeugwerke provided the necessary resources and production capabilities, while test pilot Erich Warsitz provided valuable feedback which guided necessary changes and improvements to the design.

It was a novel idea to use rockets to power aircraft, which offered numerous advantages, such as reaching high speed and altitude very quickly. Given that this project was more or less a Heinkel private venture in the development of new technologies it likewise did not find a place in German military service. It, however, did set the stage for future designs like the Me 163, which actually saw some combat during the war.

He 176 Specifications
Wingspans	4 m / 13 ft 1 in
Length	5 m / 16 ft 4 in
Height	1.4 m / 4 ft 7 in
Wing Area	8 m² / 53 ft²
Engine	Walter RI rocket engine
Empty Weight	1,570 kg / 3,455lbs
Maximum Takeoff Weight	2,000 kg / 4,400 lbs
Maximum Speed	700 km/h / 435 mph
Endurance flight Range	60 seconds
Crew	One Pilot
Armament	None

Gallery

Illustration by Godzilla

Credits

• Written by Marko P.
• Edited by Henry H. & Ed J.
• Illustration by Godzilla

Sources

• D. Nešić (2008), Naoružanje Drugog Svetskog Rata Nemačka Beograd
• M. Griehl (2012) X-Planes German Luftwaffe Prototypes 1930-1945, Frontline Book
• D. Mondey (2006). The Hamlyn Concise Guide To Axis Aircraft OF World War II, Bounty Books.
• D. Donald (1998) German Aircraft Of World War II, Blitz Publisher
• J. R Smith and A. L. Kay (1972) German Aircraft of the Second World War, Putnam
• Jean-Denis G.G. Lepage (2009), Aircraft Of The Luftwaffe 1935-1945, McFarland & Company Inc
• L. Warsitz (2008) The First Jet Pilot The Story of German Test Pilot Erich Warsitz Pen and Sword Aviation

Nazi Germany (1944) Parasite Interceptor – None Built 

The Sombold So 344 was a highly specialized interceptor designed by Heinz G. Sombold to attack Allied bomber formations over Germany in 1944. The way the aircraft would attack, however, would be extremely unconventional. Being deployed from a bomber mothership, the So 344 would fly towards an approaching bomber formation and launch its entire nose cone, which was a 400 kg (882 Ib) rocket, at the enemy bombers in an attempt to destroy as many as possible. From there, the So 344 could either attack the remaining bombers or return to base and land on a skid. Work went as far as wind tunnel models for the aircraft but none would be built.

History

Towards the end of the Second World War, Germany found itself at odds on an almost daily basis against the threat of Allied bombers. While pre-existing aircraft were used to defend Germany from this threat, more and more proposals for aircraft designed to deal with enemy bombers began to emerge. A number of these projects would use extremely unorthodox or downright strange methods to attempt to destroy enemy bombers. These ranged from carrying specialized weapons to even ramming the bomber. These projects were often small in design and were made of widely available materials, like wood, to save on production costs, reserving the more important material for mainline aircraft. An aircraft produced in small numbers that followed this formula was the Bachem Ba 349 “Natter”. Although not used operationally, the Ba 349 was a small bomber interceptor that would not require an airstrip to take off. Instead, it would be launched vertically from a launch rail. After taking off, the Ba 349 would approach the Allied bombers and attack them with a salvo of rockets in the nose. With its ammo depleted, the pilot would then eject from the aircraft, with the aircraft’s engine section parachuting down and being recovered for reuse. The nose would break off for the pilot to deploy the rockets under the cone. The Ba 349 is the most well known of these projects, but many would never leave the drawing board. Many of these aircraft designs were created by large companies but a handful came from individual engineers. One such design, the Sombold So 344, would approach the destruction of enemy bombers in an entirely different, almost ludicrous way.

The Sombold So 344 was the idea of Heinz G. Sombold of the Bley Ingenieurbüro (Engineering Office). Bley Segelflugzeug was a sailplane manufacturer located in Naumburg, Germany. During the 1930s, they became popular for their various sailplane designs, like the Kormoran and Motor-Kondor designs. Heinz G. Sombold was an engineer at Bley. He began working on the So 344 in late 1943 and his aircraft incorporated many features of the sailplanes built by the company. At the time, the craft was only designed as a parasite escort fighter and armed with two machine guns. On January 22nd of 1944 however, Sombold would drastically change the design and purpose of the aircraft. From here, the aircraft would be designed for the destruction of enemy bombers. To fit this new role, it would use a very unorthodox weapon. The nosecone of the So 344 was a rocket filled with 400 kg (880 Ib) of explosives that could be launched by the pilot at enemy aircraft. Sombold envisioned his aircraft using its nosecone rocket against close formations of bombers, where multiple aircraft could be destroyed with one well placed explosive. American bombers would often fly in combat box formations, where the bombers would fly close together to maximize the defensive capabilities of their guns. This allowed the bombers to have ample protection from enemy interceptors, as the approaching craft would come under fire from most of the aircraft in said formation. There were earlier weapons deployed by the Germans to try and damage the closely packed formations, like the BR 21, but none would be as huge a payload as the Sombold’s nose rocket.

Design work on the So 344 continued through 1944, even going as far as having a ⅕ scale wind tunnel model being made and tested at the Bley facility. By 1945, work on the project was cut off, as the Bley facility had to be abandoned due to the encroaching warfront. No further work was done on the Sombold So 344 and Sombold’s fate is unknown. No other designs by Sombold are known to have existed. The 344 designation was later used for the Ruhrstahl X-4, or RK 344, air-to-air missile system.

A photo has circulated in several books, as well online, that claims a nosecone of the So 344 was built and discovered by the Allies at the end of the war. However, this photo actually depicts the nose section of a Wasserfall surface-to-air missile. The nose of the Wasserfall easily could be confused for that of the Sombold’s, as its shape is semi-similar and both have four stabilizing fins. No So 344 was built.

Design

The Sombold So 344 was a single man special attack aircraft. It was to have a short, tubular body of wooden construction. For ease of transport, the aircraft could be split into two sections. The cockpit would be located at the rear of the body, directly in front of the vertical stabilizer. The aircraft would have conventional control surfaces on its wings and stabilizers. At the ends of the horizontal stabilizers were two angled vertical stabilizers. The wings would be mid-set. For its powerplant, the So 344 would use a Walter 509 bi-fuel rocket engine. To conserve fuel, the aircraft would be deployed via bomber mothership. Once deployed, it would have around 25 minutes of fuel. To land, the So 344 would have a rounded ski built into the body, similar to how the sailplanes Bley created would land.

For its main armament, the So 344 had a massive unguided rocket as its nose cone. The nose would contain 880 Ibs (400 kg) of explosive Acetol. The rocket was triggered via a proximity fuse. For stabilization, four fins would be placed on the nose. Additionally, the So 344 would have two forward machineguns to either defend itself or attack other bombers once its payload was released.

Operations

The So 344 would be carried to an approaching bomber formation via a modified bomber mothership. Once deployed, the aircraft would move in an arc towards the bombers, coming in downwards at them from at least 3,300 ft (1,000 m) above. This height would protect the So 344 from defensive fire during its dive. When the aircraft was lined up with a group of bombers, the pilot would launch the nosecone into the middle of the formation. Given the close proximity of the bombers in formation and the explosive threshold of the nosecone, it was predicted the resulting explosion would be able to take down several bombers in one attack. After launching its nosecone, the So 344 would have some fuel left and could continue to attack the remaining bombers with two machine guns on the aircraft. When fuel was low, the aircraft would return to base via gliding, like the Messerschmitt Me 163B rocket interceptor. Once near an airfield, it used a large ski to land.

Conclusion

The So 344 was a very strange way of approaching the bomber problem over Germany late in the war. The logic behind it was not too far fetched. The aforementioned Ba 349 Natter followed a similar attack plan, approaching the bombers and firing off a salvo of rockets before the pilot bailed from the craft. A project like the So 344 was not new to Germany by that point in the war and, like most of its contemporary designs, was not produced.

Had it been produced, the So 344 would have been a very niche aircraft. The fact that the aircraft had a single shot from its rocket payload made accuracy extremely important. The aircraft also would have been a prime target for Allied escort fighters once it ran out of fuel. A bomber would also need to be modified to carry the So 344 and would be a prime target for the escort fighters once the attacker was launched. The nature of the aircraft has led it to wrongly be named a “suicide attacker” by many postwar books on the subject. In some instances, the craft is also incorrectly listed as being a ramming aircraft. It is likely the aircraft would not have impacted the war very much.

Variants

• Sombold So 344 (1943)– Original planned fighter version. Armed with two machine guns or heavier armament. None were built
• Sombold So 344 (1944)– The Sombold So 344 attack aircraft. Armed with a nosecone rocket which would be fired at enemy bomber formations. None were built.

Operators

• Nazi Germany – The Sombold So 344 was designed for the Luftwaffe to use against Allied bombers over Germany. None of the type would be built.

Sombold So 344 Specifications
Wingspan	18 ft 8 in / 5.7 m
Length	22 ft 11 in / 7 m
Height	7 ft 1 in / 2.2 m
Wing Area	64.58 ft² / 6 m²
Engine	Walter 509 Bifuel rocket engine
Weight	2,976 Ib / 1,350 kg
Flight Time	25 minutes
Crew	1 pilot
Armament	2x machine guns 1x 880 Ib (400 kg) Nose Rocket

Gallery

Video

Credits

• Article by Marko P.
• Edited by Henry H. and Stan L.
• Illustration by Ed Jackson
• Herwig, D. & Rode, H. (2003). Luftwaffe Secret Projects: Ground Attack & Special Purpose Aircraft. Hinckley, England: Midland Pub.
• http://www.luft46.com/misc/so344.html

Nazi Germany (1944) Jet Fighter – 1 Incomplete Prototype Built 

During the war, German scientists and engineers managed to develop and build a number of jet powered aircraft, several of which went on to see combat. What is generally less known are the large number of experimental jets that were proposed and prototyped. These designs utilized a great variety of engines, airframes, and weapons. One of these unfinished projects was the Messerschmitt P.1101 jet fighter.

Need for a New Jet Fighter

During the war, the Germans introduced the Me 262, which had the honor of being the first operational jet fighter in the world. While it provided better performance than ordinary piston powered aircraft, it was far from perfect. The greatest issues were that it was expensive to build, required two jet engines, and could not be built in sufficient numbers. The German Air Ministry (Reichsluftfahrtministerium; RLM) wanted a much simpler and cheaper design powered by a single engine. They issued a competition for a new jet fighter ,code named 1-TL-Jäger, during July 1944 for all available aircraft manufacturers. Some of the requirements listed were that it would be a single seater, have a maximum speed of 1000 km/h (620 mph), an endurance of at least one hour, armor protection for the pilot, make use of the Heinkel HeS 011 engine, and had an armament that had at least two 30 mm (1.18 in) MK 108 cannons. During a meeting with the leading German aircraft manufacturers held in September 1944, Messerschmitt presented the P.1101designed by Waldemar Voight.

The Messerschmitt P.1101 Development History

Messerschmitt’s engineers and designers began working on designing a single engined jet aircraft at the start of 1943. Two projects, P.1092 and P.1095, were both powered by a single Jumo 004 jet engine, but, as the Me 262 was entering full production, their development was largely suspended. These projects were shelved until the RLM competition in 1944. Seeing a new opportunity, Messerschmitt presented drawings of a new project named P.1011, which was influenced by the previous projects. It had an all-metal fuselage construction and was powered by one HeS 011 engine with the air intakes placed on the wing’s roots. It also had a V-tail.Following the meeting with the RLM officials in September, some changes were made to the P.1101’s overall design. Instead of two air intakes, a single one in the nose was to be used. This also necessitated the redesigning of the cockpit, which was moved back. In addition, the rear V-tail was replaced with a standard fin design. At this early stage, the possibilities of using this aircraft for other purposes were still being explored. Beside the standard fighter, other roles which were considered were night fighter and interceptor. On 10th November, the owner of the company, Willy Messerschmitt, issued orders to begin working on the first experimental prototype. To speed up the developing time, it was proposed to reuse the already produced components of the Me 262. The Me 262 fuselage, wings design and construction were to be copied.

End of the Project

The P.1101 prototype was only partially completed in early 1945. It appears that, despite Messerschmitt’s attempts to complete this project, the RLM simply lost interest. Messerschmitt’s other projects, like the P.1110 and P.1111, showed greater potential than the P.1101. This, together with the fact that the promised engine never arrived, meant that the single incomplete prototype was put into storage at the Messerschmitt Oberammergau research center. It remained there until the war’s end, when it was captured by American forces.

Technical Characteristics

The P.1101 was a single seater, jet engine-powered mixed construction fighter. The lower parts of the all-metal fuselage were designed to house the jet engine. In the front of the fuselage, a round shaped intake was placed. To the rear, the fuselage was additionally reinforced to avoid any damage due to the heat of the jet exhaust. The underside of the fuselage was to have a skid to help better land during an emergency.While it was originally intended to be powered by the HeS 011 engine, the power plant was never supplied and the Jumo 004B was to be used as a replacement. The main fuel tank, with a capacity of 1,100 liters (290 gallons), was placed just behind the cockpit. Only a mock-up engine was ever installed in this aircraft, so it was never tested properly, even on the ground. Due to this, it is unknown what the P.1101’s overall flight performance would have been. Some sources give rough estimates, such as that it could have reached 890 km/h (550 mph) at sea level and up to 980 km/h (610 mph) at higher altitudes. Of course, these are only estimations contingent on the fact that the plane had no other problems during operational flight. In addition the general ability to test flight characteristics in the transonic-supersonic range were extremely crude at this point.

The wing’s were made of wood materials. The prototype would have a completely innovative feature, namely the sweep angle of the wings could be adjusted at different angles ranging between 35° and 45°. The rear vertical and horizontal tail assembly was also made of wood.The P.1101 had a retracting tricycle-type landing gear. It consisted of one forward mounted and two mid-fuselage wheels. All three retracted rearwards into the fuselage. The cockpit had a round shaped canopy with good all around vision.

The basic armament configuration consisted of two MK 108 cannons with 100 rounds each. These were placed in the front lower part of the fuselage. There were proposals to increase the firepower by adding two more MK 108 cannons, and the use of experimental air-to-air missiles was also considered. As the prototype aircraft was built to test overall flight performance, no armament was ever installed.

In American Hands

Advancing American soldiers reached the Messerschmitt Oberammergau base during April (or May) 1945. The single P.1101 was found there and, for some time, left open to the elements. The Bell Aircraft Chief Designer Robert Woods came to know of the existence of this aircraft. Once he had a chance to examine it, he organized for it to be shipped back to America for further study. It would be restored and used as testing mock up aircraft. The Bell aircraft design bureau paid great interest to the variable wing design. Working from the P.1101, they would eventually develop the Bell X-5, one of the first operational aircraft that could change the position of its wings during flight.

Conclusion

While incorporating the innovative feature of variable swept wings, the P.1101 was another victim of the chaotic state Germany was in at the end of war. Whether this aircraft could have performed its role is unknown, and while it never flew for the Germans, it helped the Americans develop the Bell X-5 after the war which incorporated the same variable wing design.

P. 1101 Specifications
Wingspans	27 ft / 8.24 m
Length	30 ft 1 in / 9.13 m
Height	9 ft 18 in / 2.8 m
Wing Area	170 ft² / 15.8 m²
Engine	One Jumo 004B or one HeS 011
Empty Weight	5,725 lbs/ 2,600 kg
Maximum Takeoff Weight	8,950 lbs / 4,060 kg
Fuel Capacity	1,100 l / 290 Gallons
Estimated Maximum Speed	610 mph / 980 km/h
Estimated Cruising speed	550 mph / 890 km/h
Crew	1 pilot
Armament	Two 108 MK cannons

Credits

• Article by Marko P.
• Edited by Stan L. and Henry H.
• Illustrated by Carpaticus
• D. Nešić, (2008). Naoružanje Drugog Svetsko Rata-Nemačka. Beograd.
• D. Monday. (2006). The Hamlyn Concise Guide To Axis Aircraft Of World War II, Bounty Books.
• D. Sharp (2015) Luftwaffe Secret Jets of the Third Reich, Mortons Media Group
• M. Griehl (2012) X-Planes, Frontline Books
• R. Ford (2000) German Secret Weapons of World War Two, MBI Publishing
• Jean-Denis G.G. Lepage (2009) Aircraft of the Luftwaffe 1935-1945, McFarland and Company
• J. R. Smith and A. L. Kay (1972) German Aircraft of the Second World War, Putnam
• http://www.luft46.com/mess/mep1101.html

Germany (1944) Experimental VTOL Fighter – Paper Project

During the war, German aviation engineers proposed a large number of different aircraft designs. These ranged from more or less orthodox designs to hopelessly overcomplicated, radical, or even impractical designs. One such project was a private venture of Focke-Wulf, generally known as the Triebflügel. The aircraft was to use a Rotary Wing design in order to give it the necessary lift. Given the late start of the project, in 1944, and the worsening war situation for Germany, the aircraft would never leave the drawing board and would remain only a proposal.

History

During the war, the Luftwaffe possessed some of the best aircraft designs and technology of the time. While huge investments and major advancements were made in piston engine aircraft development, there was also interest in newer and more exotic technologies that were also being developed at the time, such as rocket and jet propulsion. As an alternative to standard piston engine aircraft, the Germans began developing jet and rocket engines, which enabled them to build and put to use more advanced aircraft powered by these. These were used in small numbers and far too late to have any real impact on the war. It is generally less known that they also showed interest in the development of ramjet engines.

Ramjets were basically modified jet engines which had a specially designed front nozzle. Their role was to help compress air which would be mixed with fuel to create thrust but without an axial or centrifugal compressor. While this is, at least in theory, much simpler to build than a standard jet engine, it can not function during take-off. Thus, an auxiliary power plant was needed. It should, however, be noted that this was not new technology and, in fact, had existed since 1913, when a French engineer by the name of Rene Lorin patented such an engine. Due to a lack of necessary materials, it was not possible to build a fully operational prototype at that time, and it would take decades before a properly built ramjet could be completed. In Germany, work on such engines was mostly carried out by Hellmuth Walter during the 1930s. While his initial work was promising, he eventually gave up on its development and switched to a rocket engine insead. The first working prototype was built and tested by the German Research Center for Gliding (Deutsche Forschungsinstitut für Segelflug– DFS) during 1942. The first working prototype was tested by mounting the engine on a Dornier Do 17 and, later, a Dornier Do 217.

The Focke-Wulf company, ever keen on new technology, showed interest in ramjet development during 1941. Two years later, Focke-Wulf set up a new research station at Bad Eilsen with the aim of improving already existing ramjet engines. The project was undertaken under the supervision of Otto Ernst Pabst. The initial work looked promising, as the ramjets could be made much cheaper than jet engines, and could offer excellent overall flying performance. For this reason, Focke-Wulf initiated the development of fighter aircraft designs to be equipped with this engine. Two of these designs were the Strahlrohr Jäger and the Triebflügel. The Strahlrohr had a more conventional design (although using the word conventional in this project has a loose meaning at best). However, in the case of the Triebflügel, all known and traditional aircraft design theory was in essence thrown out the window. It was intended to take off vertically and initially be powered by an auxiliary engine. Upon reaching sufficient height, the three ramjets on the tips of the three wings would power up and rotate the entire wing assembly. It was hoped that, by using cheaper materials and low grade fuel, the Triebflügel could be easily mass-produced.

The Name

Given that these ramjet powered fighter projects were more a private venture than a specially requested military design, they were not given any standard Luftwaffe designation. The Triebflügel Flugzeug name, depending on the sources, can be translated as power-wing, gliding, or even as thrust wing aircraft. This article will refer to it as the Triebflügel for the sake of simplicity.

Technical Characteristics

Given that the Triebflügel never left the drawing board, not much is known about its overall characteristics. It was designed as an all-metal, vertical take-off, rotary wing fighter aircraft. In regard to the fuselage, there is little to almost no information about its overall construction. Based on the available drawings of it, it would have been divided into several different sections. The front nose section consisted of the pilot, cockpit, and an armament section for cannons and ammunition, which were placed behind him. Approximately at the centre of the aircraft, a rotary collar was placed around that section of the fuselage. Behind it, the main storage for fuel would be located. And at the end of the fuselage, four tail fins were placed.

This aircraft was to have an unusual and radical three wing design. The wings were connected to the fuselage while small ramjets was placed on their tips. Thanks to the rotary collar, the wings were able to rotate a full 360o around the fuselage. Their pitch could be adjusted depending on the flight situation. For additional stability during flight, the tail fins had trailing edges installed. The pilot would control the flying speed of the aircraft by changing the pitch.  Once sufficient speed was achieved (some 240 to 320 km/h (150 to 200 mph)), the three ramjets were to be activated. The total diameter of the rotating wings was 11.5 m (37  ft 8  in) and had an area of 16.5 m² (176.5 ft²).This unusual aircraft was to be powered by three ramjets which were able to deliver some 840 kg (1,1850 lb) of thrust each. Thanks to ramjet development achieved by Otto Pabst, these had a diameter of 68 cm (2.7 ft), with a length of less than 30 cm (0.98 ft). The fuel for this aircraft was to be hydrogen gas or some other low grade fuel. The estimated maximum speed that could be achieved with these engines was 1,000 km/h (621 mph). The main disadvantage of the ramjets, however, was that they could not be used during take-off, so an auxiliary engine had to be used instead. While not specifying the precise type, at least three different engines (including jet, rocket, or ordinary piston driven engines) were proposed.

In the fuselage nose, the pilot cockpit was placed. From there the pilot was provided with an overall good view of the surroundings. The main issue with this cockpit design wass the insufficient rear view during vertical landing.

The landing gear consisted of four smaller and one larger wheels. Smaller wheels were placed on the four fin stabilizers, while the large one was placed in the middle of the rear part of the fuselage. The larger center positioned wheel was meant to hold the whole weight of the aircraft, while the smaller ones were meant to provide additional stability. Each wheel was enclosed in a protective ball shaped cover that would be closed during flight, possibly to provide better aerodynamic properties. It may also have served to protect the wheels from any potential damage, as landing with one of these would have been highly problematic. Interestingly enough, all five landing wheels were retractable, despite their odd positioning.The armament would have consisted of two 3 cm (1.18 in) MK 103s with 100 rounds of ammunition and two 2 cm (0.78 in) MG 151s with 250 rounds. The cannons were placed on the side of the aircraft’s nose. The spare ammunition containers were positioned behind the pilot’s seat.

Final Fate

Despite its futuristic appearance and the alleged cheap building materials that would have been used in its construction, no Triebflügel was ever built. A small wooden wind tunnel model was built and tested by the end of the war. During this testing, it was noted that the aircraft could potentially reach speeds up to 0.9 Mach, slightly less than 1,000 km/h. The documents for this aircraft were captured by the Americans at the end of the war. The Americans initially showed interest in the concept and continued experimenting and developing it for sometime after.

In Modern Culture 

Interestingly, the Triebflügel was used as an escape aircraft for the villain Red Skull in the 2011 Captain America: The First Avenger movie.

Conclusion

The Triebflügel’s overall design was unusual to say the least. It was a completely new concept of how to bring an aircraft to the sky. On paper and according to Focke-Wulf’s engineers that were interrogated by Allied Intelligence after the war, the Triebflügel offered a number of advantages over the more orthodox designs. The whole aircraft was to be built using cheap materials, could achieve great speeds, and did not need a large airfield to take-off, etc. In reality, this aircraft would have been simply too complicated to build and use at that time. For example, the pilot could only effectively control the aircraft if the whole rotary wing system worked perfectly. If one (or more) of the ramjets failed to work properly, the pilot would most likely have to bail out, as he would not have had any sort of control over the aircraft. The landing process was also most likely very dangerous for the pilot, especially given the lack of rear view and the uncomfortable and difficult position that the pilot needed to be in order to be able to see the rear part of the aircraft.

The main question regarding the overall Triebflügel design is if it would have been capable of successfully performing any kind of flight. Especially given its radical, untested and overcomplicated design, this was a big question mark. While there exist some rough estimation of its alleged flight performances, it is also quite dubious if these could be achieved in reality. The whole Triebflügel project never really gained any real interest from the Luftwaffe, and it is highly likely that it was even presented to them. It was, most probably, only a Focke-Wulf private venture.

Triebflügel Estimated  Specifications
Rotating Wing diameter	37  ft 8  in / 11.5 m
Length	30 ft / 9.15 m
Wing Area	176.5 ft² / 16.5 m²
Engine	Three Ramjets with 840 kg (1,1850 lb) of thrust each
Empty Weight	7,056  lbs / 3,200 kg
Maximum Takeoff Weight	11,410 lbs / 5,175 kg
Climb Rate to 8 km	In 1 minute 8 seconds
Maximum Speed	621 mph / 1,000 km/h
Cruising speed	522 mph  / 840 km/h
Range	1,490  miles / 2,400 km
Maximum Service Ceiling	45,920 ft / 14,000 m
Crew	1 pilot
Armament	Two 3 cm MK 103 (1.18 in) and two 2 cm (0.78 in) MG 151 cannons

Gallery

Credits

• Article by Marko P.
• Duško N. (2008)  Naoružanje Drugog Svetsko Rata-Nemačka. Beograd.
• D. Sharp (2015) Luftwaffe Secret Jets of the Third Reich, Dan Savage
• Jean-Denis G.G. Lepage (2009) Aircraft of the Luftwaffe 1935-1945, McFarland and Company
• J.R. Smith and A. L. Kay (1972) German Aircraft of the Second World War, Putham
• http://www.luft46.com/fw/fwtrieb.html

Nazi Germany (1943) Night fighter – Approximately 2,520 Built

Developed from converted fighter versions of the Ju 88A-4 medium bomber, the Ju 88G would take up a growing role in the German night fighter force, as it saw its greatest successes in the Spring of 1944, and its decline in the Autumn of that same year. While built mostly as a result of the German aviation industry’s failure to produce a new specialized night fighter design, the Ju 88G would nonetheless prove to be a valuable asset, one that far exceeded the capabilities of its predecessors and was well suited for mass production.

Hunting in the Dark: 1943

1943 was a year of highs and lows for the Luftwaffe’s night fighter force, one that saw their tactics change considerably to match those of RAF’s Bomber Command. The year started with the Luftwaffe continuing the heavy use of its long standing fixed network of defensive ‘Himmelbett’ cells. These contained searchlights, radar, and night fighters that coordinated to bring down raiders. This chain of defenses stretched across the low countries through northern Germany in a network known more broadly as the ‘Kammhuber line’, named after its architect and initial commander of the German night fighter force, Josef Kammhuber. However the British would develop tactics to shatter this line and employ countermeasures to blind the radars used both by flak and fighter directors, and night fighters.

They employed what became known as the ‘bomber stream’, deploying their aircraft in a long and narrow formation in order to penetrate as few of the Luftwaffe’s defensive boxes as possible. It was a simple but effective tactic, a night fighter could only intercept so many planes, and the cells were quickly overwhelmed. When they coupled this tactic with radar reflecting chaff, which they called ‘window’, the result was the near total collapse of the German air defenses during the July raid against the city of Hamburg. With German radar scopes clouded by the resulting interference, they were unable to direct gun laying radar for their anti-aircraft guns, and night fighters could not be vectored onto their targets, much less find anything using their on-board radar systems. Virtually defenseless and in the grips of a hot, dry summer, Hamburg suffered a level of destruction eclipsed only by the raid on Dresden when the war was coming to a close.

The Luftwaffe’s disaster over Hamburg forced them to reform their strategy and develop new detection systems that would be unaffected by the newest RAF countermeasures. Kammhuber was sacked, though not exclusively as a result of the raid, and a new system of night fighter control was to be the primary means of nightly strategic air defense. Instead of the heavy focus on the fixed Himmelbett boxes, night fighters would be assembled over beacons before being directed towards bomber streams. This would ensure there would be no bottlenecks and would allow the full strength of the night fighter force to, as it was hoped, be brought against the enemy in mass. They would also employ new equipment, modifying their Wurzburg radars, used for fire and aircraft direction, with a chaff discriminating device, and replacing the older Lichtenstein (B/C) aerial search radars with the new SN-2.In the winter of 1943, Bomber Command set out to try and knock Germany out of the war. They launched a series of large-scale raids against major industrial cities and the capital, with Sir Arthur Harris, its C-in-C, believing he could end the war without the need for a costly invasion of the continent (Overy 339). The Luftwaffe’s new weapons and tactics would quickly prove their worth during what later became known as the ‘first Battle of Berlin’. Bomber Command held that a loss rate of 5% represented “acceptable losses” and significantly higher values could spell trouble for continuous operations (Brown 309). Between August and November of 1943, the casualty rates during the “1st Battle of Berlin” sat at 7.6-7.9%, figures which would climb slowly over the following months (Overy 342). However, while most Luftwaffe planners were enthusiastic about the new air defense methods, they would have to confront a growing concern in the service: they were reliant on considerably dated night fighter designs.

The Search for a New Design

Throughout much of 1943, the night fighting mission was taken up mostly by variants of the Bf 110, followed by the Ju 88, and in much smaller numbers the Do 217 and He 219. In order to address the lack of a mass produced, specialized night fighter design, three new proposals were introduced. The first being the Ta 154 “Moskito,” a wooden, dedicated night fighter design which hoped to capture the same success as the British aircraft which bore the same name. The second, the He 219, was a specialized night fighter design championed by the very man who had devised the Himmelbett system, Josef Kammhuber. Lastly the Ju 188, a bomber that at the time still lacked a night fighter version, was proposed for conversion (Aders 72).The Ta 154, despite high hopes for the project, never came to fruition as a result of its troubled development. The He 219 was sidelined by Generalflugzeugmeister (Chief of Procurement and Supply) Erhard Milch, who opposed increasing the number of specialized airframes in favor of mass production of multipurpose designs (Cooper 265). To make matters worse for the project a number of technical issues prolonged development, the aircraft took around 90,000 hours to produce, and with comparatively little support from the Luftwaffe, few were built (Cooper 325). The aircraft would, however, still be employed with the Luftwaffe, but in limited service. The Ju 188 design that likely would have received Milch’s support simply never materialized.

With the failure to find a new design, it was clear that the brunt of future night fighting would fall on existing designs, in particular the Ju 88. In early 1943, it was on this design that hopes were placed for a high performance, specialized night fighter that would become available to the Luftwaffe the following year (Cooper 266).

The Old 88

Originally entering service as a medium/dive bomber in 1939, the Ju 88A was a state of the art, if somewhat conservative, design that was exceedingly versatile and easily modifiable. The airframe was sturdy, aerodynamically clean, and modular, with many components capable of being modified without necessitating major revisions to its overall design. This is perhaps nowhere more evident than the self-enclosed combined engine-radiator assemblies that allowed the powerplant and its associated cooling systems to be easily removed or replaced via connecting plates and brackets (Medcalf 106, 107, 191).Not long after its teething period subsided, the Ju 88 proved itself in a number of roles and was employed as a night fighter early in the war, as some bombers were converted to Zerstorer (long range fighter/ground attack aircraft) at Luftwaffe workshops. Several of these aircraft were subsequently handed off to night fighter squadrons by the end of 1941, the first set with their dive brakes still equipped (Aders 31). However, by the end of 1941, small quantities of serial-built Ju 88C fighters were being delivered, with a larger production run following in the subsequent years. The type would eventually take up a growing position in the night fighter force (Medcalf 166, 178). Owing to their origins as converted aircraft, the Ju 88C-6 series retained virtually the same airframe as their bomber counterparts, with some minor alterations. The bombardier and their equipment were removed and an armament of three 7.92 mm MG17’s, a 20mm MG 151/20, and a pair of 20mm  MG FF cannons were installed in the nose of the aircraft and in the “gondola” beneath the nose that would have otherwise carried the bombsight and ventral gunner (Medalf 319).

The night fighting capabilities of the C-6 were good but its shortcomings were becoming more apparent as the war progressed. By early 1943, it was considered relatively slow and this was particularly worrying in the face of the RAF’s growing use of the Mosquito as a bomber and pathfinder, an aircraft which no German night fighter in service was able to effectively intercept. When flying at high speeds and altitudes, catching these aircraft was often more a matter of good fortune than anything else. In mid 1943, an interim design known as the Ju 88R was introduced in the hopes of alleviating some of the deficiencies of the preceding series. Despite remaining very capable in the anti-heavy bomber role, it had no hope of intercepting the Mosquito. While the Ju 88R proved to be significantly faster thanks to the use of the much more powerful BMW 801 engines over the older Jumo 211Js, it still failed to fulfill the anti-Mosquito role that its planners hoped to achieve.

While the aircraft offered greater performance and was favored by pilots, it was still very much a simple conversion, much like the C series it was supplementing, and it was clear additional modifications were necessary to better realize the airframe’s potential. In particular, its greater engine power meant the aircraft could reach higher speeds, but that power also enabled the aircraft to exceed the limits to which the rudder was effective (Aders 73). However, despite the disappointments of the year and the failure to secure a brand-new night fighter design, the hope that a new model of specialized Ju 88 would be entering service was soon realized.

Gustav

By the end of 1943, work on the new night fighter was complete and the Luftwaffe was preparing to receive the first planes by the end of the year. The new Ju 88G-1 was developed as the successor to the previous C and R series night fighters, both consolidating production and vastly improving performance.The Ju 88V-58 was the primary prototype for the Ju 88G-1 and first flew in June of 1943 (Aders 258). It sat between the older Ju 88R series aircraft and the later Ju 88G in design and appearance, using the same basic airframe as the Ju 88R and its BMW 801 power plants. However, it also incorporated the vertical stabilizer designed for the Ju 188, used a new narrower, low drag canopy from previous fighter models, and removed the “gondola” which carried a portion of the aircraft’s armament in previous models (Aders 132; Medcalf 191, 192). The armament was significantly improved with the addition of a mid-fuselage gun pod which mounted four MG 151/20 20 mm cannons, making use of the space otherwise taken up by bombing gear, with another pair of cannons installed in the nose of the aircraft. However, the nose mounted pair were removed later on due to issues regarding the muzzle flash of the guns affecting the pilot’s vision, a resulting shift in the aircraft’s center of gravity, and interference with nose mounted radar aerials (Medcalf 191).

After this series of changes to the aircraft’s fuselage, armament, and the subsequent addition of an SN-2c radar, the Ju 88G went into production. 6 pre-production Ju 88G-0 aircraft and 13 Ju 88G-1s were completed by the end of 1943 (Medcalf 178). The production switch between the previous Ju 88R and 88C models to the G was relatively smooth, with the first three aircraft delivered to the Luftwaffe in January of 1944. Production and deliveries of the new model increased sharply over the following weeks thanks to the aircraft sharing most of its components with older models (Aders 129). Mass production was carried out rapidly, with 12 planes completed a month later in January, roughly doubling the next month, and rising to 247 aircraft in June, before gradually falling as the production of its successor, the G-6, began to supersede it (Medcalf 240).

The Ju 88G-1 went into production with an offensive armament of four forward facing 20 mm MG 151/20 cannons in a pod mounted ventrally near the center of the aircraft. Upward facing cannons in the fuselage, in a configuration referred to as ‘Schräge Musik’, were often installed later at field workshops. These upward facing weapons were of particular use against British bombers, which had forgone ventral defensive guns. This armament was a marked improvement over the three 20 mm cannons and three MG 17 7.92 mm machine guns carried by the preceding C6 and R series (Medcalf 319).

The aircraft was powered by the much more powerful BMW 801 G-2 engines producing 1740 PS, a huge boost up from the Jumo 211J, 1410 PS, on the Ju 88C-6. This allowed the aircraft to reach 537 km/h at an altitude of 6.2 km, quite a considerable improvement over the Ju 88C-6’s 470 km/h at 4.8 km (Junkers Flugzeug und Motorenwerke 7, 12, Medcalf 319). The engines were unchanged from that of the previous Ju 88R model, though it was able to make better use of them thanks to the enlarged vertical stabilizer which granted better control and stability at high speed.

G-6 

To build on the success and production base of the first design, work began on a successor. Retaining the same airframe, the G-6 would be powered by the Junkers Jumo 213 A-1 and would standardize the use of equipment commonly added to the G-1 at Luftwaffe workshops. To this end several new prototypes were produced, these being Ju 88V-108, V-109 which included the MW50 boost system, and Ju 88V-111 which served as a production prototype (Medcalf 192).The aircraft carried with it several key improvements over the initial model. It was faster, better armed, and possessed a more advanced set of electronic warfare equipment. However, it’s top speed is difficult to ascertain given the limited number of sources on the aircraft. It was able to achieve 554 km/h (344 mph) at 6km (19685 ft) without the use of the MW50 boost system, and after the war Royal Navy test pilot Eric Brown was able to reach a top speed of 644km/h (400mph) at an altitude of 9,145 meters in tests (30,000ft) (Medcalf 319, Eric Brown 195). In all likelihood, this was a testing aircraft that was using either Jumo 213E or 213F engines, as 9km was well above the full throttle height of the Jumo 213A. Alternatively, some of these engines may have made their way into very late production G-6 aircraft.

The new standardized equipment included an upward firing pair of 20 mm cannons, the FuG 350 Naxos Z radar detector, and they would later be the first night fighters to be equipped with the new SN-2R and Naxos Zr tail warning equipment. They also carried the new Neptun radars for twin engine fighter use and were the only aircraft that made use of the SN-3 and Berlin search radars (Medcalf 319, 324; Aders 181). 

The SN-2R was a rearward facing radar aerial added to the SN-2d search radar sets that would warn the crew of pursuers. It helped to significantly improve survivability along with the new Naxos Zr, which could now warn the crew of enemy night fighter radar emissions. These systems quickly showed their worth. Ju 88G-6’s fared better in the presence of enemy night fighters than the He 219’s and Bf 110’s, which lacked standardized tail warning equipment (Aders 181).

Late G-6’s were also equipped with the FuG 120A Bernhardine. This device was intended to make use of a nationwide network of high powered transmitters that would have been unjammable by the RAF’s electronic warfare equipment. The system would provide the altitude of a bomber stream, its location on a grid map, its course, strength, and the recipient night fighter’s bearing from the ground station. All of this information was relayed in coded messages by means of a teleprinter in the cockpit of the night fighter. It was mostly foolproof, but the system was not fully operational by the war’s end (Medcalf 325; Price 237, 238).

Pilot’s Remarks and General Flight Characteristics

As with the rest of the Ju 88’s in the night fighter service, the plane had the ergonomics and handling characteristics that were so sought after by pilots. The sorties they faced by this point of the war were as long as two hours and as such undemanding flight characteristics were a crucial feature of any night fighter (Aders 23). Stability, well balanced controls and the ability to fly well on one engine were crucial factors, and having them made the Ju 88G a highly rated aircraft among the force (Aders 31, 132). Its reinforced airframe also came in useful, as its earlier use as a dive-bomber required a high tolerance for g-forces that made it capable of pulling off hard maneuvers without risk of damaging the airframe in the process. The addition of the Ju 188’s vertical stabilizer also improved handling markedly, as the newer design provided much smooth rudder controls over the previous version, which had ones unchanged from older bomber models and were quite stiff once the aircraft was brought up to speed (Medcalf 304).

The G-1 handled exceedingly well, with controls that were well balanced and responsive. Praise for the Gustav’s handling could even be found outside the ranks of the Luftwaffe, as Roland Beamont, an RAF fighter pilot and post war test pilot, had a chance to take one up and evaluate how it performed at RAF Tangmere in the summer of 1945. Beamont found the aircraft undemanding, with gentle controls and that, on landing, the aircraft “could be steered on the approach as gently and responsively as any fighter”. Equally as important, he found the aircraft needed very little adjustment in the air, with only very minor trimming of control surfaces needed for smooth operation in regular flight. In a rare chance, he even found an opportunity to have a mock battle with another RAF pilot, Bob Braham, flying a DeHavilland Mosquito. Beamont found the 88 was able to hold its ground for some time, but eventually letting up when he began to reach the limits of the unfamiliar plane so low to the ground and in the wake of Bob’s plane, which promptly outmaneuvered him.Despite his praise for the aircraft’s flight characteristics, he felt the structural cockpit framework was very restrictive of the pilot’s vision. In a summary of his first flight and a second on July 16th, he claimed “It has remained in my rating as one of the best heavy piston-engined twins of all time and a very pleasant flying experience.” (Medcalf 294, 295). Much like Beamont, most Luftwaffe pilots were very satisfied with the aircraft (Aders 132).

Famed Royal Navy pilot Capt. Erik ‘Winkle’ Brown would also be among the few allied pilots to have the opportunity to fly both the G-1, and subsequent G-6 model. Capt. Brown felt the aircraft possessed largely the same excellent handling characteristics as the Ju 88A-5 he’d flown prior. He praised the aircraft for its easy ground handling, thanks to its excellent brakes, it’s good handling during climbs, and light controls at cruising speed (Brown 190).

Capt. Brown would spend more time with the G-6 and was able to put one through more demanding tests. Having previously flown several versions of the Ju 88, Brown was particularly impressed by the aforementioned high speeds achieved by a Ju 88G-6 (Werk-nr 621965) he’d flown in tests. The aircraft remained in line with his general, glowing remarks over the Ju 88. “It was a pilot’s airplane, first and last, it demanded a reasonable degree of skill in handling and it responded splendidly when such skill was applied. There was a number of very good German aircraft but, with the exception of the Fw 190, none aroused my profound admiration as did the Junkers ‘eighty-eight’ (Brown 195).”

Perhaps the simplest but greatest advantage the aircraft had in night fighting was in the close proximity of the crewmembers, which allowed them easy communication in the event of intercom failure or emergency. It also allowed the pilot to be seated beside their radar operator, with the flight engineer seated directly behind him, an ideal arrangement providing both easy communication and good situational awareness, which became a necessity as bomber streams became the hunting grounds for RAF night fighters (Aders 132).

While it inherited the benefits of the original design, it also had its flaws, the most obvious of which was the poor visibility due to the bars of the reinforced cockpit frame, and the troublesome landing gear which had a tendency to buckle if the aircraft was brought down too hard (Medcalf 75). The landing gear was a hydraulically actuated set that rotated 90 degrees so that the wheels would lie flat within their nacelles. This greatly reduced drag, as the shallower landing gear bays contributed far less to the frontal area of the plane, but they could be broken in forced landings or careless flying. These types of accidents were typically handled by the airfield ground staff, though handing off the plane to a recovery and salvage battalion could prove necessary in the event of a forced landing or a particularly bad accident (Medcalf 62).

Lichtenstein SN-2

Perhaps the most important feature of the Ju 88G, its radar, was easily the weakest point of the aircraft in comparison to its contemporaries in foreign service. Unlike the British or Americans, the Germans lacked any major production of centimeter band search radars, forcing them to rely on meter band types. In practical terms, the meter band radar carried with it several major disadvantages, the most evident and visible of which were the large aerial antennas which protruded from the aircraft’s fuselage and created significant drag. In tests by the Luftwaffe’s Rechlin test pilots, it was found that the Lichtenstein (B/C) decreased the maximum speed of a Bf-110 by 39.9 km/h (Aders 44). Another major disadvantage was its inferior ability to cut through ground clutter, leading to very poor performance at lower altitudes and making it useless near ground level (Aders 163, 200).The standard Ju 88G-1 was equipped with the Lichtenstein SN-2c, also designated as FuG 220. This airborne radar set was designed by Telefunken for naval service and originally rejected by the Luftwaffe earlier in the war. Its initial rejection was based on its extreme minimum range of 750 meters, which meant that any target would disappear off the scopes long before the pilot would be able to see it (Aders 79, 80). Its later adoption was a matter of the previous air search radar having a relatively short maximum range, and that the SN-2 would be unaffected by the chaff that made the previous sets useless (Brown 309). However, due to the shortcomings of the original SN-2, the device was coupled with a simplified version of the older Lichtenstein  FuG-212 radar to track targets within the large minimum range of the new system.  The resulting set up required the use of 5 radar scopes and was an exceedingly cumbersome display, with three scopes devoted to the older Lichtenstein set and two for the SN-2 (Price 196).

The SN-2 carried by the 88G was an improved model which had its minimum range decreased to an acceptable distance, allowing it to drop the excess equipment for the far simpler SN-2c, which required only two scopes (Aders 122). The system had a frequency range of 73/82/91 MHz, a power output of 2.5 kW, an instrumented range of 8km, a minimum range of 300 m, a search angle with an azimuth of 120 degrees, an elevation of 100 degrees, and a total weight of 70 kg. While the system had a maximum instrumented range of 8km, its practical detection range was tied to the altitude at which it was operating and the size of the target. For example, if searching for a heavy bomber traveling at the same altitude, and with the maximum antenna aperture towards the Earth being roughly 30 degrees, and at an operating altitude of 5km, the slant range of the radar can be placed roughly at the system’s maximum range of 8km (Bauer 12, 13). This range increases or decreases correspondingly with the altitude of the aircraft or its target, with the device being virtually useless near ground level. One SN-2c was eventually recovered by the RAF when an inexperienced crew landed their plane at RAF Woodbridge as a result of a navigation failure, which allowed the British to develop both effective chaff and electronic jamming countermeasures for it (Price 221). This same aircraft would be the one given such a good review by Roland Beamont, its registration code being 4R+UR.

The SN-2 would see further development even as its usefulness declined in the face of widespread jamming and chaff which targeted its operating bands. The SN-2d was the most immediate development which helped to some degree. Its operating frequencies were shifted to the 37.5-118 MHz dispersal band to make use of its still usable frequencies that were not fully targeted by RAF jamming efforts. It would later be combined with the SN-2R tail warning radar and, very late in the war, made use of low drag ‘morgenstern’ aerials and an aerodynamic nose cone which fit over it (Aders 244).

Late War and Experimental Radars

The FuG 217/218 Neptun radar sets were developed and built by FFO. These had been initially developed for use in single engine night fighters, but were later adapted for use aboard twin engine aircraft. They were largely a stop gap following the RAF jamming efforts against the SN-2, as any new aerial search radar was months away. These series of radars came in a variety of configurations as they were further developed and pressed into wider service. The Neptun 217 V/R was a search radar that could switch between two frequencies between 158 and 187 MHz, had a search angle of 120 degrees, a maximum range of 4 km with a minimum of 400 meters, and a total weight of 35 kg. The subsequent Neptun 218 V/R search radar included four new frequency settings along the same range, had a maximum range of 5km with a minimum of 120 meters, a power output of 30kW, weighed 50kg, and possessed the same search angle as the previous model. Both radars could be mounted in a “stag antler” array with the preceding Neptun 217 V/R also having a “rod” type mounting arrangement, which consisted of individual antennas attached to the airframe. As with the SN-2, tail warning sets were produced which were found in the form of the standalone Neptune 217 R and Neptun 218 R sets, or as a component of the Neptune 217 V/R and Neptun 218 V/R combined search and tail warning radars. (Aders 245, 246).

The FuG 228 SN-3 was developed by Telefunken and was visually similar to the SN-2 but with thicker dipoles. The device operated on a frequency range of 115-148 MHz, had a power output of 20kW, a maximum range of 8km with a minimum of 250m, a search angle with an azimuth of of 120 degrees, an elevation of 100, and a total weight of 95kg. Some sets also made use of a low drag “morningstar ” array that used ¼ and ½-wavelength aerials. 10 sets were delivered for trials and may have been used in combat (Aders 245).

The FuG 240 Berlin was another radar developed by Telefunken and their last to see operational use during the war, it also being the first and only centimetric aerial search radar to see service with the Luftwaffe. It operated on a wavelength of 9 to 9.3 cm, an output of 15kW, had a maximum range of roughly 9 km, a minimum of 300 m, a search angle of 55 degrees, weighed 180 kg, and had no serious altitude limitations (Aders 246, Holp 10). While only twenty five Berlin sets were delivered to the Luftwaffe they made successful use of them in March of 1945 (Aders 246; Brown 317). While these new devices were free of the heavy jamming the SN-2 faced, they lacked the larger production base of the SN-2 which continued to be fitted to new night fighters until the end of the war.

Passive Sensors

While the SN-2 radar was somewhat mediocre, this deficiency was offset by other devices that were often installed aboard which could supplement it, these being the FuG 227 Flensburg and FuG 350 Naxos Z. Developed by Telefunken, Naxos was able to detect the emissions of British H2S ground mapping radar and other devices with frequencies in the centimeter band. This would enable a night fighter equipped with the system to home in on RAF aircraft that were using ground mapping radar to direct bomber streams to their targets. The Naxos Z set was capable of detecting emissions at up to 50 km, enabling them to find pathfinders or simply other bombers in the stream as the ground mapping radar became more commonplace among the aircraft of Bomber Command (Price 176, Medcalf 325). Subsequent models would expand the reception band to allow the device to detect British centimetric aerial intercept radar and combine the system with tail warning equipment to alert aircrews to the presence of British, and later American, night fighters, with the series working within the 2500 mHz to 3750 mHz band (Medcalf 325). These included the Naxos-Zr, used exclusively in Ju 88s, with the aerial contained within the fuselage, the Naxos ZX, which further increased the detectable frequency ranges, and the Naxos RX, which was a version of the previous type which coupled it with tail warning equipment (Aders 248, 249). This was solely a directional sensor and would give the operator the azimuth of the target, but not its altitude or range.

Flensburg was another passive device, this one made by Siemens. While Naxos detected the emissions from RAF ground mapping radar, Flensburg picked up the tail warning radar of RAF bombers, a device codenamed Monica. With later versions operating on a tunable frequency band of 80 mHz to 230 mHz, it allowed aircraft equipped with it to detect virtually all bombers traveling within a stream should their rear warning radar be active (Medcalf 325). Among the captured pieces of equipment in Ju 88G [4R+UR], this was evaluated by the RAF and found to be an exceedingly useful tool for detecting and closing in on their bombers. The aircraft with the device was evaluated by Wing Commander Derek Jackson in a series of tests with both a single RAF Lancaster bomber and a small group of five planes flying over a considerable distance. He found that, in both cases, he was able to home in on the bombers with the Flensburg device alone from as far as 130 miles away without any issues even when the aircraft were in close formation, where there was hope that several of the tail warning radars operating closely together might have confused the device (Price 222).In all, 250 Flensburg sets were produced, alongside roughly 1,500 Naxos-Z sets, and though only the latter became standard equipment, both saw extensive use among Ju 88 night fighters (Aders 124). These devices proved incredibly successful in combination with SN-2 and, for several months, allowed the German night fighter forces to achieve great operational success. However, they eventually fell behind again one final time after the successful British efforts to counter the Luftwaffe’s sensors and tactics in the months following the landings in France (Brown 319). In the end only Naxos remained the only reliable means of detecting raiders as, unlike Monica, they could not do without their H2S ground mapping radar.

Initial Deployments

Field use of the aircraft began shortly after the delivery of the first pre production aircraft, which were quickly sent out to units equipped with older models of Ju-88s, often being placed into the hands of formation leaders. In this way, its introduction into service was gradual, with the first aircraft already being in the hands of more experienced pilots before more deliveries allowed for the entire unit to transition away from older models. Prior to July of 1944, Gruppe IV of NJG3, II and III of NJG6, and I of NJG7 were supplied with large numbers of G-1s, followed by a gradual supply to NJG2, Gruppe IV of NJG 5, III of NJG3, and NJG100. It should also be noted that these aircraft could be found in the inventories of most units, even those that did not fully transition over fully to their use (Aders 131).

For the first three months of 1944, the Luftwaffe inventory had only a single digit number of operational G-1s but, by April and May, mass deliveries of the aircraft began, with 179 planes available in May and 419 by July (Aders 272). A total 1,209 Ju 88G-0s and G-1s were delivered to the Luftwaffe between December of 1943 and October of 1944, with the aircraft and its successor, the Ju 88G-6, becoming the mainstay of the German night fighter force for the remainder of the war (Medcalf 178, 240).

Zahme Sau: Winter through Spring

As a heavy radar equipped night fighter, the Ju 88G would serve the Luftwaffe as “Zahme Sau” (Tame Boar) interceptors. They differed from “Wilde Sau” (Wild Boar), in that they were to receive guidance toward enemy bombers from a series of ground based stations in a system known as Y-Control. With information collected from various search radars and passive radio and radar detectors scattered throughout much of Western Europe, ground control operators would direct interceptors toward bomber streams (Price 175, 178).

For much of 1944, a typical mission for a Zahme Sau pilot would go as follows. First, they would take off and head for an assembly point marked by a radio/searchlight beacon. Then, they would wait their turn before receiving radio commands directing them towards a bomber stream. The fighters were led away from the beacons by their formation leaders, but rarely did all a gruppe’s fighters actually reach the target in close order. Lastly, upon reaching the stream, they would attempt to merge with it and then begin to search out targets with on board sensors. In addition to direct guidance, Y-control gave a running commentary on a bomber stream, describing its course and the altitude range the staggered bombers flew at (Aders 102, 103,195). This running commentary was particularly useful later on when night fighters more commonly flew alone and the use of the signal beacons was restricted.

This system would see the effectiveness of the Luftwaffe’s night fighters reach its zenith in the spring. Building upon their successes of the previous winter they would inflict heavy losses on Bomber Command. Between November of 1943 and March of 1944, Bomber Command would lose 1,128 aircraft prior to the temporary withdrawal from large scale operations over Germany. During the raid on Nuremberg in April of 1944, 11.9% of raiders failed to return home in what became the costliest raid of the entire war (Overy 368). Thankfully for the Allies, the Luftwaffe would never see this level of success again, as Bomber Command shifted to support Operation Overlord at the end of May. While Arthur Harris wished to continue his large-scale area bombing campaign over Germany, he would relent to pressures from higher offices and place his forces in support of the coming operation to liberate France. The subsequent raids against various rail yards across coastal France would prove a well needed respite for Bomber Command. The short distance the raiders flew over hostile territory meant that Luftwaffe night fighters had fewer opportunities for interception, and thus Bomber Command’s losses were comparatively light.

RAF Tactics and Changing Fortunes

Following Overlord, Bomber Command returned to Germany better equipped and prepared for the challenges ahead. A typical late war Bomber Command heavy raiding force was composed mostly of Lancaster and Halifax heavy bombers which were supported by airborne  radar and radio jammers, night fighters, decoy formations composed of trainee squadrons, and chaff dispersing aircraft. In addition to the aforementioned Lancaster and Halifax, the B-17 and B-24 were also used by both the USAAF and RAF as electronic warfare platforms during these raids, though in much smaller numbers. Several variants of the DeHavilland Mosquito would be used as pathfinders, bombers, and nightfighers. The pathfinders were particularly troublesome as they could outpace any interceptor, save for a night fighter variant of the Me 262 that was introduced near the end of the war. While goals of the heavy bombers were straightforward, the supporting forces’ goal was to disorient Luftwaffe ground controllers and engage their night fighters to reduce operational losses and tie up enemy aircraft (Aders 194, 195).Locating the stream proved difficult, but if a fighter was to infiltrate it, they were mostly free of electronic interference and would encounter little resistance. While successful infiltration often meant good chances for kills, most night fighters would end up returning to base having expended most of their fuel in the search.

While the Luftwaffe’s system was still holding steady it soon faced a new challenge, as from December 1943 onward, German night fighter pilots would also have to contend with the long-range Mosquito night fighters of the RAF’s 100 Group. Tasked with supporting bombing raids through offensive action, they operated by seeking out German night fighters over raid targets, at night fighter assembly points, and lastly to seek out enemy aircraft near the stream itself (Sharp & Bowyer 289). By the beginning of May 1944, 100 Group possessed only about a hundred Mosquitos, though the number would grow larger and they would begin to replace their older and less capable aircraft (Sharp & Bowyer 290, 291). In the Autumn of 1944, the Mosquitos began to carry equipment to track German night fighters by activating their Erstling IFF (Identify Friend or Foe System) by mimicking the signals of German search radars. With this new gear and their bolstered numbers, they had tied down much of the Luftwaffe night fighter force by the winter of 1944. Eventually, the Germans left their IFFs off, which made tracking their own planes extremely difficult, and forced them to abandon the use of the assembly beacons which were frequented by the Mosquitos (Aders 196). Understandably, the Mosquito became the source of constant anxiety for Luftwaffe night fighter crews. The Mosquito typically made its appearance during takeoffs, landings, and when the often unsuspecting German night fighters were transiting to and from their targets. Under such circumstances, the use of tail warning and radar detecting equipment aboard the Ju 88G was both an important defensive tool, and a serious morale booster.

Despite its earlier successes, the Luftwaffe’s night fighter force’s effectiveness began its decline in August of 1944 in the face of general disruptions to their detection and communication capabilities as the Allies deployed radar and radio jammers to the continent (Aders 194, 195, 197). This loss of early warning radar coverage would prove a decisive blow to the Luftwaffe, one that they never recovered from.

Blind and Deaf: Autumn into Winter 

As summer turned to autumn, night fighter bases were increasingly harassed by Allied daylight fighter bombers, which forced the Luftwaffe to disperse their forces to secondary airfields. While these “blindworm” locations were free of prowling Mosquitos and fighter bombers, they were not without their disadvantages. While these fields were well camouflaged, their rough landing fields could be hazardous and they were not cleared for night landings. This forced many night fighters to land at their more well-constructed bases after their nightly sorties and return to the camouflaged fields in the evenings. The result was a rise in losses as the aircraft were occasionally caught by Allied fighters on their flight back. Through late 1944 and into 1945, German night fighter losses were most commonly the result of interception in transit or being hit on the ground. While at first only bases in Belgium and the Netherlands were threatened, Allied fighters would appear in growing numbers over the skies of Western and Southern Germany, as would the recon aircraft that periodically uncovered the “blindworm” bases (Aders 197).

In September of 1944 the night fighter force flew a total of 1,301 sorties against approximately 6,400 enemy aircraft, of which they brought down approximately 76, representing a loss rate of 1.1%. Bomber Command losses had fallen significantly from the 7.5% of the previous year, and from last April’s catastrophic high of 11.9%. As such, Bomber Command losses were once again well below the 5% attrition threshold for continuous operations (Aders 197).By the start of winter, the RAF and USAAF had largely succeeded in jamming most of the Luftwaffe’s early warning radars, y-control radio services, and through the use of chaff and jammers, made the standard SN-2 search radar useful only in the hands of experts. This had the overall effects of ensuring the night fighter force was slower to respond in-bound raiders, more likely to be sent against diversionary formations, and that night fighters were far less likely to make contact with the bomber stream after being vectored toward it. By winter, it had become clear for the Luftwaffe that the after hours war over Western Europe had been irrevocably lost.

While the night fighter force had some success in finding alternatives to their models of the SN-2 air search radars there was no hope of recouping their past successes. Between the chronic fuel shortages, marauding RAF Mosquitos, mounting ground and transit losses, and the compromised performance of most of the Luftwaffe’s ground based radars, the situation had become unsalvageable. Its decline was final, and in February of 1945, the force disintegrated as the Allies took the war into Germany (Aders 201). After almost a year following its greatest successes, the Luftwaffe’s night fighter force finished the war mostly grounded for lack of fuel and as night harassment forces in support of Germany’s depleted and hard pressed army (Aders 206).

On the Offense

In conjunction with their interception duties, many units equipped with Ju 88Gs would conduct night ground attack operations against Allied forces in France against the Normandy beachhead, and later across the Western front in support of Operation Wacht am Rhein at the end of 1944.

On the night of August the 2nd, 1944, the first of these operations were carried out against various targets, including the disembarkation area at Avranches and the Normandy bridgehead. The operation code-named ‘Heidelburg’ was conducted by elements of NJG’s 2, 4, and 5.These attacks were conducted without the use of bombs and were regarded by some as absurd due to the extreme danger in conducting low level strafing runs at night, and with only limited preparations being made before the operation (Boiten P4 25). The attacks would be carried out until the night of the tenth with the night fighters taking considerable, but inconsistent, losses.

On the night of the sixth, one Ju 88G would claim an unusual victory in this period as during their return flight,  Lt. Jung of 6./NJG2. Jung and his R/O Fw. Heidenrech detected and closed in on P-38 of the 370th fighter squadron at around 2:30 near Falaise, which they subsequently downed. Not all the aircraft had the same luck as Jung, as during the same night another Ju 88G of his Gruppe would be brought down by an Allied night fighter. The aircraft proceeded to crash into a Panther tank belonging to the 1st SS Panzer Division, resulting in a two hour traffic jam during that unit’s counter attack on Mortain (Boiten P4, 28). The overall impact these missions had were largely undefinable due to the inability to accurately survey the damage inflicted.

While infrequent attacks were carried out during the Autumn of 1944, the Luftwaffe’s night fighters would not be committed to any major ground attack operations until the end of the year. On the night of December 17th, several night fighter squadrons would be called upon for night ground attack operations in support of Operation Wacht Am Rhein. This action saw roughly 140 Ju 88’s and Bf 110’s of at least seven Gruppen being committed to what was to become the Battle of the Bulge (Boiten P3, 65).

These night raids did considerable damage and sowed confusion amongst rear-echelon services, as vehicles initially traveled with undimmed lights and many facilities failed to observe black out conditions. This was especially true against rail and road traffic which, until then, felt safe traveling at night. These mistakes placed otherwise safe trucks, trains, depots, and barracks in the sights of night fighters sent on massed area raids, and armed reconnaissance patrols. These attacks were typically carried out by strafing, and bombing in the case of modified aircraft, which were equipped with ETC 500 bomb racks. During the nightly ground attack operations during the Battle of the Bulge, these modified aircraft typically carried a pair of AB 250 or AB500 cluster bombs which themselves contained either SD-1 and SD-10 anti-personnel submunitions.These attacks were particularly effective on the odd night with higher visibility. On the night of the 22nd of December, 23 Bf 110G’s and Ju 88G’s belonging to the I. and IV./NJG 6 flew interdiction missions around Metz-Diedenhofen. Owing to the good weather that night they were able to successfully attack several targets, which included some 30 motor vehicles credited as destroyed, and several trains which they attacked north of Metz. They were joined that night by seven aircraft from I.NJG4 which undertook low level strafing attacks, for which they were credited for the destruction of one locomotive, four motor vehicles, and a supply dump. Additionally, they were credited for damaging another locomotive, six motor transport columns, and five single motor vehicles. Losses amongst the night fighters were uncharacteristically light that night, with only Bf 110 G-4 2Z+VK having been lost during the raids (Boiten 73).

The operational conditions during these raids were generally very poor, both a result of the weather, which had infamously grounded most aircraft during the initial stages of the battle, and Allied electronic interference. While the navigational aids and avionics of their aircraft made them effectively all weather capable, the harsh weather and Allied jamming of navigation beacons and radio communications proved serious challenges to Luftwaffe night fighter crews. The difficult nature of the missions themselves made for little improvement, as they typically flew at low altitudes under weather conditions which reduced visibility. The sum of all of these factors made for missions which brought on significantly more fatigue than the typical bomber interception mission.Throughout the battle, the Ju 88G would prove an exceptional night ground attack aircraft or ‘Nachtschlachter’. With its powerful engines, cannons, large payload, and exceptional de-icing systems, the aircraft could carry out attacks under very harsh winter conditions. Several of these aircraft would have their radar removed and were used exclusively for this mission until the end of the war. A number of former night fighters would even serve with the bomber squadron KG2, with their cannon armament removed, as night attack aircraft (Medcalf Vol.2 618).

The raiders encountered few night fighters as several RAF Mosquito night fighter units had been withdrawn to requip with the new Mosquito NF Mk. XXX. Between the two USAAF squadrons with their P-61’s and the remaining RAF units, there were few Allied night fighters in the area (Aders 200). However, Luftwaffe losses to AAA were high thanks to the advanced centimetric gun-laying radars in use with the US and British armies. In the end the night fighters were able to cause disruptions behind allied lines, but the price paid was steep, with 75 aircraft being lost over 12 nights (Boiten P5 3).

Operation Gisela:

The Ju 88G would play an exclusive role in the last major Luftwaffe night action of the entire war, in a large-scale intruder mission dubbed Operation Gisela. This operation was likely formulated after Maj. Heinz-Wolfgang Schnaufer discovered that night fighting conditions on the other side of the ‘front’ were far more favorable. He later submitted a proposal to his fighter division to attack Allied bombers over the North sea, where there would be relatively little electronic and chaff interference, and where the bombers would least suspect an attack. However, the CO of the 3rd fighter division would instead propose to attack the bombers at their airfields when they were landing.

In any case the British intelligence services got wind of the plan as was made clear by the broadcasting of the song ‘I dance with Gisela tonight’ over a propaganda station. The attack would be postponed several times until early March, 1945 (Aders 205).

About 100 Ju 88G’s were dispatched in three waves to follow a bomber stream as it departed for home. Upon reaching their destination the first wave would down twenty two bombers, however the fires from the wrecks would ruin the chances of the subsequent waves. While many bombers were saved by flying to different airfields after being alerted by the flames, eight more were wrecked attempting to land at darkened airstrips. However, the night fighters would face a dangerous return trip as they had to chart a course using dead reckoning and astral navigation due to their signal beacons being jammed (Aders 205). In the end, the night fighters would suffer a similar level of losses to the bombers they were hunting as a result of ground fire, crashes resulting from low level flight, and navigation failures. Operation Gisela would end in failure with no subsequent missions being attempted.

Construction 

Fuselage 

The Ju 88A-4 was the most widely produced bomber variant and provided the foundations for the C, R, and G types. It was a fairly conventional all metal aircraft in its construction, and, while it pushed few technical boundaries, it was state of the art and versatile. It was primarily made of sheet aluminum fastened by rivets, with cast parts used for load bearing elements. Some use of Elektron magnesium alloy was made to further reduce weight, with sparing use of steel where strength was required, particularly in the landing gear assemblies and fuselage connecting elements. The fuselage cross section was rectangular with rounded corners and clad in large sheet aluminum stampings. It used a semi-monocoque structure made up of formers and bulkheads joined by connectors that ran front to aft, with the outer aluminum skin riveted to both elements, which allowed it to bear some of the structural load. Its structural load factor was 4.5 with a 1.1 multiplier for the first wrinkle, 1.3 for yield, and 1.8 for failure. In service, it proved very sturdy, with Junkers engineers claiming after the war that there had been no reported major structural failures over the service life of the airframe (Medcalf  41,43,73).Eventually, the construction process had been improved to the point where the fuselage could be built from sub-assemblies that would become the upper and bottom halves of the fuselage. These would then be joined together after the internal components were fitted. Wing construction followed a similar process, making heavy use of sub assemblies, followed by equipment installation, skinning, and painting. An early model Ju 88 took roughly 30,000-man hours to complete. By the end of 1943, this number remained about the same for the Ju 88G-1. While this may seem unimpressive at face value, the night fighter carried an airborne radar system and a much more sophisticated set of avionics (Medcalf 41-43; Adders 183).

Wings and Stabilizers

The Ju 88’s wings were the heaviest part of the aircraft, comprising much of its total structural weight at over 1200 kg. A pair of massive main spars ran from the root to the wing tip, a rear spar ran across the entire span of the wing to support the flaps and ailerons, and two forward spars ran from the engine nacelles to the fuselage to transfer thrust from the engines and support loads from the landing gear. These spars were joined by relatively few airfoil shaped ribs and stiffened with corrugated aluminum (Medcalf 41-43). The wings were joined to the fuselage by means of four large ball connectors, which made for easy assembly and alignment. (Medcalf 73).

The vertical stabilizer was fixed to the fuselage by means of the same ball-screw connectors as the wings. Installing it was simple, with the rudderless stabilizer being fitted to the fuselage, and the rudder fin being affixed afterwards. The horizontal stabilizers did not use the same fitting system. Instead, they were each inserted into the fuselage by two spars which were then bolted together. This process was virtually the same on both the Ju 88A and the Ju 188, save for the latter having a fin which was 42% larger by area and a rudder which was 68% larger than the previous model (Ju 88A-4 Bedienungsvorschrift-FL Bedienung und Wartung des Flugzeuges; Ju 188E-1(Stand Juni 1943); Medcalf 123). The Ju 88G would incorporate the larger vertical stabilizer from the Ju 188 to improve stability and control at high speed.

As previously stated, the landing gear could prove troublesome due compromises in its design. During early prototyping, JFM (Junkers Flugzeug- und Motorenwerke) redesigned the landing gear into a single strut that would rotate so that it would lie flat beneath the wing when retracted. While this did remove the frontal area that would have seriously impacted the aircraft’s high speed performance, it came at the cost of added complexity and made for a far less robust landing gear arrangement (Medcalf 74, 75). Differing from earlier series, the Ju 88G’s landing gear frames made use of welded cast steel instead of light weight alloys. The G-1 carried a maximum of 2835 liters (620 gallons) of fuel, with the subsequent G-6 likely having a reduced fuel capacity considering its shorter endurance (Report No. 8 / 151).

Engines and De-icing Systems

Among the most notable features of the Ju 88 were its use of unitized engine power units and its novel de-icing system. The unitized engine installation incorporated both the engine and associated cooling system into a single module that could be installed or removed from the aircraft relatively quickly, and made storage of components easier. These “kraftei” arrangements existed for the BMW 801 G-2, and, later, Jumo 213 A-1 engines. These engines were fitted with VDM and VS-111 propellers respectively.

Engine Type	Arrangement	Bore	Stroke	Displacement	Weight	Maximum Output	Maximum RPM	Fuel type
BMW 801 G-2	Radial 14	156 mm	156 mm	41.8 liters	1210 kg	1740 PS	2700	C3, 95 octane
Junkers Jumo 213 A-1	Inverted V-12	150 mm	165 mm	35 liters	820 kg	1775 PS [2100 PS MW50]	3250	B4, 87 octane

(Medcalf 323; Ju 88S-1 Flugzeug Handbuch 3, Smith & Creek 687; Jumo 213 13)

The aircraft was also equipped with a de-icing mechanism which took in air, ran it through a heat exchanger around the exhaust ejector stacks, drove it through channels in the wings, and then out over the ailerons (Rodert & Jackson). As the BMW 801 had no exhaust stacks compatible with this system, they made use of a petrol-fired heater to supply air to the de-icing system on the Ju 88G-1 (Report No. 8 / 151).

Cockpit

The crew arrangement on all Ju 88 models would set the entire crew within the canopy and in close contact with one another. The bombardier ,or radar operator, sat to the pilot’s right, a flight engineer/gunner at the pilot’s back, and a ventral gunner sat beside the flight engineer or in a prone position inside the “gondola”, where his weapon was located. Aboard the Ju 88G, the ventral gunner’s position had been omitted with the removal of the gondola, however the positions of the other crew members remained largely unchanged. While these close quarters arrangements were somewhat claustrophobic, they ensured easy communication between the pilot and the rest of the crew at all times. It also made for a much simpler bail out procedure, as half the canopy would detach and allow for a quick escape for all aboard. In the Ju 88G, the crew entered the aircraft through a hatch below the cockpit.

The Ju 88G’s cockpit differed heavily from previous fighter versions as a result of added instrumentation and alterations to some of the aircraft’s existing controls. Among the new additions were ammunition counters with space for representing up to six guns, and a Zeiss Revi C.12/D gunsight. This sight differed from previous sets by its new elevation controls and its lack of an anti-glare shield. The front of the canopy was protected by a 10mm armor plate, with the windscreen itself being comprised of four panes of armored glass. The three in front of the pilot were electrically heated to prevent frost formation (Report No. 8 / 151). Work was also done to revise the controls to bring them more in line with other Luftwaffe fighters, perhaps most usefully by the addition of an automatic engine control system and manual propeller pitch control switches being added to the throttles (Brown 194).

Armament

The aircraft’s initial armament consisted of four Mg 151/20 cannons and a defensive MG 131. The cannons were mounted in a ventral pod between the aircraft’s wings and supplied by ammunition belts that occupied the space used as a bomb bay on bomber variants of the airframe. The ammunition belts were loaded with an equal proportion of high explosive ‘mine-shot’, armor piercing, and general purpose high explosive shells. The single 13 mm MG 131 was placed at the rear of the canopy within an armored glass mount and supplied with 500 rounds of armor piercing and high explosive shells in equal proportion (Ju 88G-1 Schusswaffenlage Bedienungsvorschrift-Wa). An armament of upward firing 20mm cannons, being either the MG FF or MG 151/20, were often installed at Luftwaffe field workshops prior to their inclusion to the design in the production run of the G-6 model.In addition to its cannons, the aircraft could mount ETC 500 underwing racks for bombs and fuel tanks. These racks could each support bombs weighing over 1000kg, though bomb loads in service were light compared to those carried by bomber variants of the Ju 88. These were universal pylons that were added to existing aircraft, an alteration that was fairly simple given the design commonalities with the older Ju 88A-4, and newer Ju 88S medium bombers.

Avionics

In addition to its complement of detection devices, the aircraft carried a variety of tools to aid in navigation and ground direction. Ju 88G’s were typically equipped with the following devices: FuB1 2 (Blind approach receiver), Fug 10P (radio set), FuG 25 (IFF), FuG 101 (Radio altimeter), and the FuG 16zy (radio set).

The FuB1 2 was a blind landing system that guided the aircraft onto a runway by way of two radio beacons placed at 300 m and 3000 m away from one end of the airstrip. It was a tunable device so that airfields could possess separate frequencies between 30 and 33.3 mHz. The aircraft itself carried the Eb1 2 beacon receiver, the Eb1 3F beam receiver, the FBG 2 remote tuner, the AFN 2 approach indicator, the U8 power supply unit, and either a mast or flush antenna (Medcalf 324).

The FuG 10P was a radio developed by Telefunken and was coupled with the Pielgeräte 6 radio direction finder. The device consisted of numerous transmitters and receivers capable of operating at various ranges. One pair, E10 L and EZ 6, operated at between 150-1200kHz, and another, S10 K and E10 K, between 3-6mHz. Other components included the U10/S and U10/E power supply units, and the fixed antenna loading unit AAC 2. Numerous versions existed and made use of various other components. Much of this system was later removed during the production run of the Ju 88G-6 (Medcalf 324).

The FuG 25 “Erstling” was an IFF system manufactured by GEMA that would respond with coded impulses to the ground-based Wurzburg, Freya, and Gemse radar systems up to a range of 100 km. The receiver operated on a frequency of 125 mHz and the transmitter at 160 mHz. The entire unit was contained within the SE 25A unit, with the BG 25A control box in the radio operator’s station (Medcalf 324).

FuG 101 was a radio altimeter designed by Siemens/LGW with a maximum range of 150-170 m and operated on a frequency of 375 mHz at 1.5 kW. Accuracy was within 2 m and the entire system weighed 16 kg. It consisted of the S 101A transmitter, E 101A receiver, U 101 power supply unit, and the pilot’s panel indicator (Medcalf 325).

The FuG 16zy “Ludwig” was a radio manufactured by Lorenz and used for fighter control and directional homing, operating on a frequency range of 38.5 to 42.3 MHz. In Ju 88 night fighters it usually accompanied the Fug 10P radio gear which sat just below the defensive machine gun at the rear of the canopy. It could be set to different frequencies for the Y-control communication system: Gruppenbefehlswelle [between aircraft in formation], Nachischerung und Flugsicherung [between the pilot and the ground control unit], and Reichsjagerwelle [running battle commentary] (Aders 242). It was composed of the S16 Z Tx transceiver, E16 Z and U17 power supply systems, and the loop phasing unit ZWG 16 along with the antenna (Medcalf 324).

The FuG 120A ‘Bernhardine’ was a radio positioning device designed by Siemens to provide navigational assistance and bomber stream intercept information to night fighters by means of a teleprinter in the aircraft’s cockpit. It was intended to overhaul the night fighter force’s air to ground communication infrastructure which faced significant signals interference from the RAF, but the war ended before it entered large scale service. Aircraft could be directed over a range of 400km with position bearings accurate within .5 degrees from ground stations (Medcalf 325, Price 238, 239).

Emergency Equipment

The Ju 88G would share the same emergency gear as the Ju 88S, this being stowed in a compartment at rear of the fuselage. The largest items of the set were an inflatable raft and an emergency radio beacon, with the contents of the entire compartment being sealed in a waterproof cloak (Ju 88S-1 Flugzeug Handbuch 64).

Production

Junkers Flugzeug und Motorenwerke AG was the sole manufacturer of the Ju 88G and, as was the case with most late war German aircraft, production was conducted at major plants in conjunction with dispersal facilities. The primary production facility for the Gustav was at Bernburg, with two dispersal plants at Fritzlar and Langensalza, each of which would eventually be able to assemble 75 aircraft every month, these being half the capacity of the main Bernburg plant (Medcalf 241, 247).

As with all major fighter projects at the time, large-scale mobilization of labor and material resources was managed by the Jagerstab, an office which built direct links with the RLM (Reichsluftfahrtministerium, the German Air Ministry), regional government officials, and industrialists in order to marshal resources for expanding fighter production. The office was created in response to increasing Allied raids against Germany’s aviation industries and the growing disparity in numbers, which began to strongly favor the Allies as they built up their forces in anticipation for the landings in France. The office was headed by Albert Speer, Minister of Armaments and War production, and aided by Erhard Milch, Generalluftzeugmeister (Air Master General). In spite of the rapidly deteriorating wartime conditions facing all German industries, the office was successful in boosting production, but relied on desperate and illegal measures (Medcalf 229,232). In the fall of 1944, a minimum 72-hour work week was standard, as was the use of forced labor under conditions that were especially poor at the dispersal sites. The acceptance of rebuilt and used parts became ever more commonplace. This, however, did little to offset the clear superiority of the Allies in the air after the Summer of 1944 (Medcalf 247).

Up until April of 1944, the aircraft was built in parallel with decreasing numbers of Ju 88C-6 and Ju 88R, as production at Bernburg transitioned over to the Gustav. Production of the Ju 88G-1 ceased in October as the factories shifted over to the Ju 88G-6 (Medcalf 240). The Bernburg plant was hit twice by the USAAF’s Eight Air Force in February of 1944, which resulted in total stoppages for only a few days, after which production quickly resumed. However, there was a projected loss of over a hundred aircraft per month compared to the averages of the previous year, with a full recovery requiring several months (Medcalf 229).

Ju 88 Production

January

February

March

April

May

June

July

August

September

October

November

December

1943

–

–

–

–

–

–

–

–

–

–

–

13 (+6 pre-production)

1944

12

26

47

169

209

247

239

143

88

10

–

–

5*

14*

138*

189*

222*

308*

178*

1945

168*

35*

19*

Ju 88G-6 production*

Ju 88G-0 Werk Nummern: 710401 through 710406

Ju 88G-1 Werk Nummern: 710407 through 714911

Ju 88G-6 Werk Nummern: 620018 through 623998

Ju 88G-7 Werk Nummern: 240123 through 240125 (~3 built)

Ju 88G-10 Werk Nummern: 460053 through 460162 (~30 built, converted to mistel air to ground weapons)

Variants:

G-0: Preproduction aircraft, the same as G-1

G-1: Production night fighter, powered by BMW 801 G-2 engines

G-2: Proposed zerstorer, powered by the Jumo 213A, was to carry a single MG 131, four MG 15’s, and two MK 103’s. No radar.

G-3: Proposed night fighter, powered by DB 603, same armament as the G-1

G-4: Proposed night fighter, powered by Jumo 213A, with GM-1 boost system

G-5: Proposed night fighter, powered by Jumo 213A

G-6: Production night fighter, powered by Jumo 213A

G-7: The same as G-6 except with Jumo 213E engines with three speed, two stage intercooled superchargers. Output: 1726 HP (1750 PS) unboosted, 2022 HP (2050 PS) with boost at 3250 RPM. Weight: 28,946 lbs (13,130 kg). Speed:  650 km/h at 7.9 km. Experimental.

G-10: Same as G-6 but with an extended fuselage.

(Medcalf 319, 178, 240; Green 448-482; Smith & Creek 687)

Conclusion:

The Ju 88G would prove a valuable asset to the Luftwaffe’s night fighter forces through its zenith, in the spring of 1944,  until its collapse nearly a year later. From a production standpoint the aircraft was phenomenal. It made use of existing supply chains and components from Ju 88 variants that had long been in service prior to its introduction, allowing for a near seamless transition into mass production. In terms of its performance, the initial model would prove exceptional, being far faster and easier to fly than the existing night fighter workhorses, the aging Bf 110G and Ju 88C. The subsequent G-6 model would prove to be even more impressive with the addition of more powerful engines and standardized tail warning equipment.While the aircraft did have its downsides and couldn’t solve every problem the night fighter service faced, it effectively fulfilled its purpose, and became the most numerous night fighter model in German service by the war’s end.

Specification Charts:

Classification	Aircraft type	Engine	Engine output	Loaded weight	Range	Maximum Speed
Bomber	Ju 88A-4	Jumo 211J	2×1400 PS (2x 1380 hp)	14000 kg, 30864lbs	2430 km, 1510 mi	440 km/h (5.5 km), 273mph (18044ft)
Zerstorer/Night fighter	Ju 88C-6	Jumo 211J	2×1400 PS (2x 1380 hp)	–	–	470 km/h (4.8 km), 292mph (15748ft)
Zerstorer/Night fighter	Ju 88R-2	BMW 801D	2×1740 PS (2×1716 hp)	–	3450 km, 2144 mi	550 km/h (6.2km), 341 mph (20341ft)
Night fighter	Ju 88G-1	BMW 801G	2×1740 PS (2×1716 hp)	12005 kg, 26466lbs	2870 km, 1783 mi	537 km/h (6.2km), 333mph (20341ft)
Night fighter	Ju 88G-6	Jumo 213A	2x 1775 PS [2100 PS], (2×1750 hp [2071 hp])	12300 kg, 27116lbs	~2400km, 1491 mi	554 km/h (6.0km), 344mph (19685ft)

(Medcalf 323, 319, 320; Smith & Creek 687)

*only the G series was tested with radar and exhaust flash hiders fitted, when equipped with these devices the C and R series flew at values lower than the ones presented on this chart

[] denotes performance with the MW50 boost system

Ju 88G-1  (Ju 88G-6)	Specification
Engine	BMW 801 G-2 (Jumo 213 A-1)
Engine Output	2×1740 PS (2x 1774PS [MW50: 2100PS]) : 2×1706 hp (2×1750 hp [2071 hp])
Empty Weight	8846 kg (9000kg) : 19502 lbs (19842 lbs)
Loaded Weight	12,005 kg (12300kg) : 26466 lbs (27117 lbs)
Maximum Range	2870 km (~2400 km) : 1784 mi  (~1490 mi)
Maximum Endurance	4 hours 35 minutes (3 hours 45 minutes)
Maximum Speed [at altitude]	537 km/h [6.2 km] : 333mph [20341ft]
Armament	4xMG 151/20 , 1xMG 131 (4xMG151/20, 2xMG 151/20, 1x MG 131)
Crew	1 Pilot, 1 Radar Operator, 1 Flight Engineer/Gunner
Dimensions	–
Length	14.5 m : 47′6 7/8”
Wingspan	20.08 m : 65′11″
Wing Area	54.5 m2 : 586.6 ft2

(Ju 88 G-2, G-6, S-3, T-3 Bedienungsvorschrift-Fl 66, 69 Part II; Ju 88G-1,R-2, S-1,T-1 Bedienungsvorschrift-Fl 49, 53 part II; Report No. 8 / 151: Junkers Ju 88 G-1 Night Fighter 2; Medcalf 323, 319, 320)

*Top speeds reflect only the initial production models and do not take into account any boost systems.

BMW 801 G-2 Low supercharger gear (January 1944)	At Height	Output	RPM	Manifold Pressure
Maximum power (3 minutes)	0.9 km	1740 PS	2700	1.42 ata
Combat power (30 minutes)	1.1 km	1540 PS	2400	1.32 ata
Maximum continuous	1.6 km	1385 PS	2300	1.20 ata
Low power, greatest efficiency	2.2 km	1070 PS	2100	1.10 ata
Low power	2.3 km	980 PS	2000	1.05 ata
BMW 801 G-2 High supercharger gear (January 1944)	At Height	Output	RPM	Manifold Pressure
Maximum power (3 minutes)	6.0 km	1440 PS	2700	1.30 ata
Combat power (30 minutes)	5.6 km	1320 PS	2400	1.32 ara
Maximum continuous	5.8 km	1180 PS	2300	1.20 ata
Low power, greatest efficiency	5.7 km	990 PS	2100	1.10 ata
Low power	5.7 km	905 PS	2000	1.05 ata

Engine rated for C3 ~95 octane fuels

(Ju 88S-1 Flugzeug Handbuch 3)

Radar System	Practical Maximum range	Minimum range	Search angle-azimuth	Search angle-elevation	Frequency	Output	Array	Other notes
FuG 220  Lichtenstein SN-2c & SN-2d	8km (instrumented)Altitude dependent	300m	120 degrees	100 degrees	73/82/91 MHz later changed to 37.5-118 MHz dispersal band	2.5kW	Stag antler (Hirschgeweih), few examples of low drag morningstar array (Morgenstern)	SN-2d had a narrower beam width, was combined with tail warning radar, and performed better against jamming. Standard production radar for the Ju 88G.
FuG 217 Neptun V/R	Altitude dependent	400m	120 degrees	–	Two click stop frequencies of 158 amd 187 MHz	–	Rod or stag antler	FuG 217R was the tail warning radar component
FuG 218 Neptun  V/R	Altitude dependent	120m	120 degrees	–	Six click stop frequencies between 158-187 MHz	–	stag antler	FuG 218R was the tail warning component
FuG 228 Lichtenstein SN-3	Altitude dependent	250m	120 degrees	100 degrees	115-148 MHz	20kW	Stag antler, morningstar	ten sets built
FuG 240/1 Berlin N-1a	~9km	300m	55 degrees	–	9-9.3cm (3,250-3,330 MHz)	15kW	Parabolic antenna	25 sets built, 10 delivered for service, 1945

This chart is only for operational and experimental radar usage aboard the Ju 88G, it does not include earlier radars or specialized sets designed for other aircraft.

*The morgenstern (eng. morningstar) aerial is often misidentified as a separate search radar or exclusive to either the SN-2d or SN-3, it is a low drag aerial arrangement compatible with either device.

~ Sources disagree

(Aders 244-246; Holp 10)

Gallery

Illustrations by Ed Jackson

Primary Sources

• Air Intelligence 2 (g) Inspection of Crashed or Captured Enemy Aircraft Report Serial No. 242 dated 16th July 1944 Report No. 8 / 151: Junkers Ju 88 G-1 Night Fighter. 1944.
• Fw-190 A-5/A-6 Flugzeug-Handbuch (Stand August 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. December 8, 1943.
• Handbuch fur die Flugmotoren BMW 801 MA-BMW 801 ML-BMW 801C und BMW 801D Baureihen 1 und 2. BMW Flugmotorenbau-Gessellschaft m.b.H. Munich. May, 1942.
• Junkers Flugmotor Jumo 213 A-1 u. C-0. Junkers Flugzeug und Motorenwerke Aktiengesellschaft, Dessau. December, 1943.
• Ju 88S-1 Flugzeug Handbuch. Junkers Flugzeug und Motorenwerke A.G., Dessau. 1944.
• Ju 88A-4 Bedienungsvorschrift-FL Bedienung und Wartung des Flugzeuges. Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. July 19, 1941.
• Ju 188E-1 (Stand Juni 1943). Junkers Flugzeug und Motorenwerke Aktiengesellschaft, Dessau. June 1, 1943.
• Ju 88G-1 Schusswaffenlage Bedienungsvorschrift-Wa (Stand Oktober 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. November, 1943.
• Ju 88 G-1,R-2, S-1,T-1 Bedienungsvorschrift-Fl (Stand November 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. December 1, 1943.
• Ju 88 G-2, G-6, S-3, T-3 Bedienungsvorschrift-Fl (Stand September 1944). 1944.
• Rodert, L. A., & Jackson, R. (1942). A DESCRIPTION OF THE Ju 88 AIRPLANE ANTI-ICING EQUIPMENT (Tech.). Moffett Field, CA: NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS. 1942.

Secondary Sources

• Aders, Gebhard. German Night Fighter Force, 1917-1945. Stroud: Fonthill, 2016.
• Bauer, A. O. (2006, December 2). Some Aspects of German Airborne Radar Technology, 1942 to 1945 [Scholarly project]. In Foundation for German Communication and Related Technologies. Retrieved from https://www.cdvandt.org/
• Bauer, Arthur O. “Stichting Centrum Voor Duitse Verbindings- En Aanverwante Technologieën 1920-1945.” Foundation for German communication and related technologies (History of Technology), December 2, 2006. https://www.cdvandt.org/.
• Boitens, Theo. Nachtjagd Combat Archive 24 July – 15 October 1944 Part 4. Red Kite . 2021.
• Boitens, Theo. Nachtjagd Combat Archive 16 October – 31 December Part 5 1944. Red Kite . 2021.
• Boitens, Theo. Nachtjagd Combat Archive, 1 January – 3 May 1945. Red Kite . 2022.
• Brown, L. A radar history of World War II: Technical and military imperatives. Bristol: Institute of Physics Pub. 1999
• Brown, Eric Melrose. Wings of the Luftwaffe. Hikoki, 2010.
• Cooper, M. The German Air Force, 1933-1945: An Anatomy of Failure. Jane’s Pub, 1981.
• Green, William. The warplanes of the Third Reich (1st ed.). London: Doubleday. pp. 448–482, 1972.
• Manfred Griehl, Nachtjäger über Deutschland, 1940-1945: Bf 110, Ju 88, He 219 (Wölfersheim-Berstadt: Podzun-Pallas-Verlag, 1999).
• Medcalf, William A. Junkers Ju 88 Volume One From Schnellbomber to Multi-Mission War Plane. Manchester, UK: Chevron Publishing Limited , 2013.
• Medcalf, William A. Junkers Ju 88 Volume Two The Bomber at War Day and Night Operational and service history. Manchester, UK: Chevron Publishing Limited , 2014.
• Holpp, Wolfgang. “The Century of Radar.” EADS Deutschland GmbH
• Holm, M. (1997). The Luftwaffe, 1933-45. Retrieved February, 2021, from https://www.ww2.dk/
• Overy, Richard James. The Bombing War: Europe 1939-1945. London: Penguin Books, 2014.
• Price, Alfred. Instruments of Darkness: the History of Electronic Warfare, 1939-1945. Barnsley, S. Yorkshire: Frontline Books, 2017.
• Sharp, C. Martin, and Bowyer Michael J F. Mosquito. Bristol: Crecy Books, 1997.
• Smith, J. R., & Creek, E. J. (2014). Focke-Wulf Fw 190, Volume 3: 1944-1945. Manchester: Crecy Publishing.

Credits

• Article written by Henry H.
• Edited by Stan L. and Ed J.
• Ported by Ed J.
• Illustrations by Ed Jackson

Nazi Germany (1934) Dive-bomber – 262-400 Built

Prior to the Second World War, the Germans were experimenting with how to increase the accuracy of air bombing attacks. One solution was to use dive attacks, which greatly increased the chance of hitting the desired targets. By the mid-30s, a number of German aircraft manufacturing companies were experimenting with planes that could fulfill these dive bomb attacks. The Junkers Ju 87 proved to be the most promising design and would be adopted for service.  The Ju 87 would become one of most iconic aircraft of the Second World War, being feared for its precise strikes, but also for its unique use of sirens for psychological warfare.

History

After the First World War, the Germans began experimenting with ideas on how to make aircraft more precise during ground attack operations. The use of conventional bombers that dispatched their payload from straight and level flight could effectively engage larger targets, such as urban centers, industrial facilities, infrastructure, etc. This method was less effective for destroying smaller targets, like bunkers or bridges. A dive-attack, on the other hand, provided a greater chance of hitting smaller targets and, to some extent, reduced the chance of being shot down by ground based enemy anti-aircraft fire. This concept of dive-attack aircraft would be studied and tested in detail by the Germans during the 1930s. These aircraft would be known as Sturzkampfbomber (dive-bomber), but generally known as Stukas.

The development of such aircraft was greatly hindered by the prohibitions imposed by the Treaty of Versailles. To overcome this, some German companies simply opened smaller subsidiaries in other countries. In the case of the Junkers, a subsidiary company known as Flygindustri was opened in Sweden. There, they developed a K 47 two-seater fighter in 1929. It was tested for the role of dive-bomber and proved successful. But its price was too high for the German Luftwaffe to accept, so it was rejected.

As a temporary solution, the Germans adopted the He 50 in 1932. The following year, a more comprehensive test of the dive-bombing concept was undertaken at airbase Juterbog-Damm. During these trials, Ju-52 bombers were used. The overall results were disappointing, thus development of a completely new dedicated design was prioritized by the Germans. For this, Luftwaffe officials placed an order with all aircraft manufacturers to present their models for the dive-bomber competition.In late 1933, the Junkers dive-bomber development project was carried out by engineer Herman Pohlmann. He stressed the importance of an  overall robust aircraft design in order to be able to withstand steep diving maneuvers. Additionally, it should have had fixed landing gear and be built using all-metal construction.

The next year, a fully completed wooden mock-up with inverted gull wings and twin tail fins was built by Junkers. Officials from the German Aviation Ministry (Reichsluftfahrtministerium RLM) inspected the mock-up during late 1934, but they were not impressed and didn’t place a production order. Despite this, Junkers continued working on the project. Junkers soon began construction of a full scale prototype. Due to many delays with the design, construction of the project dragged into October 1935. The first prototype received the Ju 87 V1 designation, bearing serial number 4921. Somewhat surprisingly, it was powered by a 640 hp Rolls-Royce Kestrel 12 cylinder engine. The first test flight was completed in September 1935 by test pilot Willi Neuenhofen. While the first flight was generally successful, the use of a foreign engine was deemed unsatisfactory and it was requested that a domestic built engine be used instead.  The V1 prototype would be lost in an accident when one of the twin tail fins broke off during a dive test near Dresden. Both the pilot Willi Neuenhofen and the second passenger, engineer Heinrich Kreft, lost their lives. The examination of the wreckage showed that the fin design was too weak and thus had to be replaced with a simple conventional tail fin.

Ju 87 V2 (serial number 4922 and with tail code  D-UHUH (later changed to D-IDQR) was built with the 610 hp Jumo 210 A engine and had a redesigned tail fin. Another addition was the installation of special slats that could be rotated at 90° forward, perpendicular to the underside of the wing, acting as dive brakes. The V2 also received a specially designed bomb release mechanism, meant to avoid accidentally hitting the lowered radiator and the propeller. When the pilot activated the bomb release during a dive, the specially designed cradle would simply swing forward. In essence, this catapulted the bomb safely away from the plane while still maintaining its trajectory toward the target. There were a number of delays with the redesign of the airframe, which led to V2’s first flight being made during late February 1936. While the test flight was successful, the Luftwaffe officials showed some reluctance with regards to the project, given the fate of the first prototype. Nevertheless, the Ju 87, together with the He 118, Ha 137 and Ar 81, were used in a dive-bomber competition. The initial results favored the Heinkel, but when the He 118 was lost during one of its  test flights together with the engine problems, the RLM proclaimed the Ju 87 as the winner.

Winning the competition for the new dive-bomber design, Junkers was instructed to build more prototypes to improve the overall performance of the Ju 87. The V3 (serial number 4923 and designation D-UKYQ) received a number of modifications. It had an enlarged tailfin, added counterweights on the elevators, a modified landing gear, and a redesigned engine cowl to improve forward visibility. The first test flight was made in March of 1936.The V4 (serial number 4924 and with D-UBIP) was further modified by once again increasing the size of the tailfin, adding forward firing machine guns, a rear defensive machine gun, and again redesigning the front engine compartment. It was powered by the Jumo 210 Aa engine. It was flight tested for the first time in June 1936. During its test flight, the maximum cruising speed achieved was 250 km/h (155 mph). The RLM would become increasingly concerned about the Ju 87 design, as this cruising speed was the same as that of the older He 50. Despite this, the handling and resilience of the whole airframe were deemed satisfactory. The V4 prototype would later serve as the base for the A-0 pre-production series. The last prototype, V5 (serial number 4925), was built in May 1936. It was built to test the installation of the DB 600 and Jumo 210 engines.

The Ju 87 ‘Anton’ Introduction

Following the success of the prototype series, the RLM officials issued orders for more Ju 87 aircraft. This would lead to a small production run of between 7 to 10 aircraft of the Ju 87A-0 pre-series aircraft (A for Anton, according to the German phonetic alphabet). While the first A-0 aircraft were to be built starting in November 1935, due to a number of delays, the actual production began in the spring of 1936. Following a series of tests conducted on the A-0 aircraft at the end of 1936, it was determined that these planes, equipped with the Jumo 210 Aa engine, were underpowered. A number of the A-0 aircraft would receive a new 680 hp Jumo 210 D engine as an upgrade. The A-0’s rear fuselage was also lowered to provide the rear gunner with a better firing arc. For the radio equipment, two ‘V’ shaped antennas were placed around the cockpit.

Further development led to the Ju 87A-1, which was powered by the Jumo 210 D as standard. The A-1 series was able to carry one 250 kg (550 lbs) bomb in its standard two man crew configuration. Alternatively, it could carry one 500 kg (1100 lbs) bomb but, in this case, the rear machine gunner had to be left behind.

The last version of the series was the Ju 87A-2. It was slightly improved by adding better radio equipment. In addition, the engine performance was improved, along with a new two-stage compressor, and a new propeller.

Technical Characteristics 

The Ju 87A was designed as a single-engined, twin-seat all metal dive bomber. Its fuselage was built by connecting two oval-shaped sections with a simple structure design. The longerons consisted of long shaped strips which spanned across the longitudinal direction of the aircraft. These had a ‘U’ shape which was connected to the duralumin skin by rivets.

For construction of the Ju 87’s wings, Junkers engineers employed the doppelüger (a double wing construction). This meant that the full-span ailerons were hinged near the trailing edge of the wings. Another feature of the wings was that they had an inverted gull design. This was done intentionally by the Junkers engineers in an attempt to provide the crew members with the best possible all around visibility. The Ju 87 fuselage and wings were covered with a combination of duralumin and magnesium alloy sheeting. While the V1 prototype was equipped with twin tail fins, the A-series was equipped with a more orthodox tail design. The tailplanes had a rectangular shape, while the rudder had a square shape.

The landing gear was fixed. It consisted of two larger front wheels, with one smaller tailwheel to the rear. The front landing gear and wheels were covered in large protective fairings, sometimes known as “spats.” This arrangement would prove to be problematic, and would later be replaced with a much simpler design.

The Ju 87 engine was mounted specifically to provide easy access for replacement or maintenance. It was powered by an inline Jumo 210 D water cooled engine, with a variable pitch propeller with a 3.3 m diameter. The fuel capacity was 480 liters, placed in two tanks. The fuel tanks were located in the center part of the curved wings.The Ju 87 had a large cockpit where the pilot and the rear gunner were positioned in a back-to-back configuration. The center of the canopy assembly was reinforced by a durable section of cast magnesium, meant to provide better structural integrity. The cockpit was also protected with a fire-resistant asbestos firewall. On the A-series, the pilot was responsible for operating the radio equipment. This task would be allocated to the rear gunner in later versions. The radio equipment consisted of a FuG VII radio receiver and transmitter.

The Ju 87A-1 was armed with one forward mounted 7.92 mm MG 17 and a rear positioned MG 15, also firing 7.92 mm, fitted on a flexible mount. The offensive armament consisted of either a 250 kg or 500 kg bomb (550 to 1100 lbs). When the larger bomb was used, the rear crew member had to be left behind. A small number of aircraft were equipped with bomb racks for four 50 kg (110 lbs)  mounted under the wings. These were actually used for training purposes, as the bombs were actually made of concrete.

Diving Operation

The Ju 87 pilot would commence the dive-bombing run once the target was identified. The target would be located through a bombsight which was placed in the cockpit floor. The attack would usually be carried out from an altitude of less than 4,600 meters. The aircraft would then be rolled around by the pilot until it was upside down. The Ju 87 would then engage its target at an angle of attack of 60 to 90°, with a speed of 500 to 600 km/h (310-370 mph). During these dive-bombing runs, there was a chance the pilot could  temporarily lose consciousness due to extensive G-forces. If the pilot was unable to pull up, a ground collision was a strong possibility. To avoid this, the Ju 87 was equipped with automatic dive brakes that would simply level out the plane at a safe altitude. Once the plane reached a level flight, the brakes would then disengage. The Ju 87 was also equipped with warning lights that informed the pilot when it was time to release the bomb.

Germans conducted extensive research to determine how much G-force a pilot could endure without any medical problems. The testing revealed that the pilot could overcome a 4G force without problems. At 5G , the pilot would experience blurred vision. The maximum G-forces were noted to be 8.5 G but only for three seconds. Any more could lead to extensive injuries or even death.

Organization

The Ju 87 were used to equip the so-called Sturzkampfgeschwader or simply StG (dive-bomber flight unit). The StG was divided into three Gruppen (groups). Each of these groups was further divided into three Staffel (squadrons).

In Combat

The Ju 87 saw its first combat action during the Spanish Civil War that lasted from 1936 to 1939. The Germans saw this war as the perfect place to test their new aircraft designs. For this reason, one V4 prototype was secretly disassembled and transported on a passenger ship to Spain in August 1936. It was part of the experimental unit (Versuchskommando) VK/88 (or VJ/88, depending on the source) of the Condor Legion. The overall performance or even the use of this aircraft is generally unknown. During this conflict, it received the designation 29-1. It may have taken part in the Battle of Bilbao  in June of 1937, after which it was shipped back to Germany.

In early 1938, three more aircraft of the A-1 series were shipped to Spain. These received the 29-2, 29-3, and 29-4 designations. They were given to the 1st Staffel of Sturzkampfgeschwader  162 (dive bomber wing).  While only three aircraft were used by this unit  their original designations were often replaced with higher numbers in an atempt to decive the enemy.  The initial pilots of these aircraft were Ernst Bartels, Hermann Hass, and Gerhard Weyert. The Germans would replace them with new crew members after some time, in the hope of increasing the number of pilots with experience operating the aircraft under combat situations.

Their initial base of operations was an airfield near Zaragoza, Spain. There were some problems with the forward landing gear covers, which would dig into the ground on the sandy soil of the airfield. To resolve this issue, the crews simply removed them. The use of a larger 500 kg bomb required the removal of the rear gunner, so the smaller 250 kg bomb load was more frequently used.

In March 1938,, the three Ju 87s attempted to attack retreating Spanish Republican units at the Aragon with somewhat limited success. The attacks were less successful, mainly due to the inexperience of the pilots. From July 1938 on, the Ju 87 showed more promising performance during the Spanish Republican failed counterattack at the Ebro River and Mequinenza. By October, all three Ju 87 As were shipped back to Germany.

The overall performance of the A-series was deemed insufficient for combat operations early on. This, together with the fact that the improved Ju 87B version was becoming available in increasing numbers, leading to a withdrawal of the A version from service. These would be reallocated to training units, and would be used in this role up to 1944.

In Hungarian Service 

During the war the Germans provided their Hungarian ally with four Ju 87A aircraft. These were used mostly for crew training in later stages of the war.

Production and Modifications

Production of the Ju 87 ended by the summer of 1938. By that time, some 262 were built by the Junkers factories located in Dessau (192) and Bremen (70). These numbers are according to M. Griehl (Junkers Ju 87 Stuka). Author D. Nešić (Naoružanje Drugog Svetsko Rata-Nemačka), on the other hand, notes a number of 400 aircraft being built.

The main versions were:

• Ju 87 Prototype series – Five prototypes were built and used mostly for testing.
• Ju 87A-0 – A small pre-production series.
• Ju 87A-1 – Main production version.
• Ju 87A-2 – Slightly improved A-1 aircraft.

Conclusion

While the Ju 87A fulfilled the role of dive-bomber well, it was shown to be inadequately developed to meet military requirements. For this reason, it was mainly issued for crew training. Its main success was that it provided the German with an excellent base for improvement and development of further aircraft. It also provided the German pilots with valuable experience in such dive-bombing flights.

Ju 87A-1  Specifications
Wingspans	45 ft 3 in / 13.8 m
Length	35 ft 4 in / 10.78 m
Height	12 ft 9  in  /  3.9 m
Wing Area	104 ft² /  31.9 m²
Engine	Junkers Jumo 210D 680 hp engine
Empty Weight	5,070 lbs / 2,300 kg
Maximum Takeoff Weight	7,500 lbs / 3,400 kg
Fuel Capacity	480 liters / 127 US gallons
Maximum Speed	200 mph / 320 km/h
Cruising speed	170 mph  / 275 km/h
Range	620 miles / 1,000 km
Maximum Service Ceiling	22,970 ft / 7,000 m
Crew	One pilot and the Rear Gunner
Armament	One forward mounted 7.92 mm MG17 and one 7.92 mm MG15 positioned to the rear One 550 lb (250 kg) bomb for two-seaster Or one  1100 lb (500 kg) bomb in the single-seater configuration.

Gallery

Illustrations by Carpaticus

Credits

• Article by Marko P.
• Edited by Stan L. & Ed J.
• Illustrations by David Bocquelet & Carpaticus
• M. Griehl (2006) Junkers Ju 87 ‘Stuka’, AirDOC.
• M. Guardia (2014) Junkers ju 87 Stuka, Osprey Publishing
• D. Nešić (2008). Naoružanje Drugog Svetsko Rata-Nemačka. Tampoprint S.C.G. Beograd.
• D. Monday. (2006). The Hamlyn Concise Guide To Axis Aircraft OF World War II, Bounty Books.
• Z. Bašić (2018) Građanski Rat U španiji 1936-1939, Čigoja Štampa.
• G. Sarhidai, H. Punka and V. Kozlik. (1996) Hungarian Air Forces 1920-1945, Hikoki Publisher

Nazi Germany (1938) Tactical Reconnaissance Aircraft – 13-18 Built

During the Second World War, the Germans would design and build a number of unusual aircraft (the Me 163 or the He 111 Zwilling, for example), but none was so unorthodox and strange as the Bv 141. In order to provide good visibility for its reconnaissance role, the crew gondola was completely separated from the aircraft’s fuselage. While small numbers were built, during testing it was shown to have decent flying characteristics for its completely unconventional design.

History

In 1937, the German Ministry of Aviation (Reichsluftfahrtministerium RLM) issued a request to all German aircraft manufacturers for a new single-engine reconnaissance aircraft with provision for three crew members. Great attention was to be dedicated to having a good all-around visibility. In addition, the aircraft would also have to be able to act as a light attack, and smokescreen laying aircraft. Three aircraft manufacturers responded to this request, Arado, Focke Wulf, and Blohm und Voss. Of these, Blohm & Voss would submit the most distinctive design to say at least.

While at first glance, the Ha 141 (as it was known at the start of the project, with the ‘Ha’ designation stands for Hamburger Flugzeugbau) appears to be created by someone with no experience whatsoever in aircraft design. This was not actually the case. In reality, the Ha 141 was designed by Dr. Ing. Richard Vogt, who was Chief Designer at Blohm und Voss for the new reconnaissance aircraft. The Ha 141 was to have an unusual design, as the crew was put into a well-glazed gondola, with the fuselage with and engine to the left. During his initial calculations, Dr. Vogt predicted, successfully, that the large crew gondola would act as a counterbalance to the long left-side engine fuselage.

When Dr. Ing. Richard Vogt presented his plans to the Ministry of Aviation, the officials were quite uninterested in such an unorthodox design, and the story of the Ha 141 would have ended there. Not willing to give up on his idea so easily, the Blohm und Voss company financed the construction of the first prototype with its own funding. The prototype was completed early in 1938  and the name was changed to Bv 141. It made its maiden flight on the 25th of February that year. The flight went well, without any major problems. The only issue was a slight oscillation of the landing gear. When it was presented to the Luftwaffe officials, they were surprised by its performance and ordered a production run of three more prototypes. Interestingly, after some negotiations with Blohm & Voss, their prototype was included in this order and two more aircraft were actually built. The first prototype was marked as V0 and would be later rebuilt into the Bv 141 V2 prototype and tested with the BMW 139F engine.  The Luftwaffe officials only requested that the crew gondola be completely redesigned, internally and externally, to incorporate a larger working space, and to be almost completely glazed, quite similar in design to the Fw 189. Bv 141 V1, actually the second produced aircraft, was used to test the aircraft’s general flight performance. The V3 made its first test flight on 5th October 1938 and was used mainly to test the BMW 132N engine.

By 1939, an additional two more aircraft were built. The V4, that was to be sent to the Erprobungstelle Testing Center at Rechlin, had an accident during landing. After the repairs were made, it was finally flight tested at Rechlin. It performed well and it was liked by the pilots that had the chance to fly it. It also underwent a number of different weapon tests. Once all these tests were completed, the V4 prototype was chosen for modification into the first A-series. After that, a small series of the A version, five aircraft in total, were built and used mostly for testing and development of new improvements at Rechlin. Some were stationed at Aufklärungsschule 1 (Training School 1) at Großenhain. While the A-2 would be rebuilt into a training airframe in May 1942, the fate of the remaining aircraft of this series is unknown. Likely, all were scrapped. Depending on the sources the A-series aircraft were powered by a 1,000 hp BMW Bramo 323 radial engine.

Following these tests, the Bv 141 received positive reports about its overall performance. There were also discussions about its mass production. Despite this, the whole project was officially canceled on 4th April 1940. The main reason was the Luftwaffe high officials’ distrust of the design. The official reason for rejection of the Bv 141 was noted as ‘underpowered,’ despite its good performance.

Technical Characteristics

The Bv 141 was a uniquely designed single-engine all-metal aircraft. It did not have a standard fuselage, with the engine in the front and the crew behind it.  The crew gondola and the fuselage with the engine were completely separate from each other. Both were located slightly off the center of the wings. The crew gondola was placed on the right, with the engine to the left.

The first A-series aircraft had a wingspan of 15 m (49 ft 3 in). The Bv 141 was initially powered by a 865 hp BMW 132N 9-cylinder radial engine. It used a constant speed propeller. Behind the engine, the 490 l fuel tank was placed.

The tail design was changed during the Bv 141’s development. Initially, a standard tail design was used. This would later be replaced with a forward leaning, asymmetric tailplane, offset to port side. The unusual shape of the new tailplane had the intent of providing the rear gunner with the best available firing arc. It only had one elevator, which had a larger surface area than the previous model. Surprisingly, the aircraft’s good performance was left unchanged after the introduction of the asymmetric tailplane.The landing gear was more or less standard for its time. The front landing gear consisted of two large wheels that retracted outwards into the leading edges of the wings. To the rear, there was a small landing wheel that retracted to the back and slightly protruded out of the fuselage.

The first crew gondola had fewer glazed surfaces than the later used models. In general, it provided the crew with excellent front, rear, and right-side views of the surroundings. The left view was partly obscured because of the engine.

The armament consisted of four 7.92 mm machine guns. Two MG 17 forward firing fixed machine guns were placed in the forward nacelle. These were operated by the pilot, who used a Revi aim sight. To the rear, one defensive MG 15 was placed in a small circular cupola atop of the Bv 141. The last MG 15 was positioned to the rear of the aircraft. The Bv 141 could also carry four 50 kg (110 lb) bombs.The pilot was positioned on the left side of the englazed nose of the gondola.  Next to him  was the position of the observer, who also acted as bombardier in case the Bv 141 was used for ground attack. The observer also had the job of operating the radio and the machine gun placed in the small circular cupola. Interestingly, because he performed different tasks, his seat was connected to two tracks which enabled him to move freely inside the gondola without getting up. The third crew member operated the rear defensive machine gun.

Last Hope for Production

With the cancelation of the Bv 141A series due to allegedly poor engine performance, Dr. Ing. Richard Vogt immediately began working on an improved version. In order to address the concerns made  by the Luftwaffe regarding its engine, the Blohm & Voss designers decided to use the stronger 1,560 hp BMW 801A 14-cylinder two-row engine. Unbeknownst to them, this decision would actually doom the whole project.

With the new engine, other changes to the overall design had to be made. The wings had to be reinforced and their span increased to 17.46 m (57 ft 3 in). In addition, the leading and trailing edges had to be redesigned. The rear part of the fuselage’s design was also changed. The landing gear was also improved by adding much stronger landing gear wheels. The armament appears to have been reduced to three machine guns (the sources are not clear here), while the bomb load remained the same.

All these changes would lead to the development of the Bv 141B series. The first mock-up was completed in February 1940. The first test flight was made on the 9th January 1941. This time, the Luftwaffe officials showed interest in it, especially after installing the much stronger engine. While Blohm & Voss received permission to build five aircraft of the B-series, the order was increased by five more. Initial calculations showed that it could reach speeds up to 480 km/h (300 mph), at least in theory. Almost immediately, the Bv 141B aircraft proved to be plagued with many problems. The controls were difficult to use and the plane was prone to mechanical faults, especially regarding the landing gear and the hydraulic systems. A huge issue was also created by the strong vibrations that occurred during the test flights. In addition, during firing trials, it was noted that cordite fumes would accumulate in the cockpit from the guns.The Luftwaffe’s initial enthusiasm for this unusual aircraft quickly faded away. While the tests on the Bv 141 would go on for a few more years, the Fw 189 would be chosen instead. Despite this setback, Dr. Vogt would continue on working on similar and improved designs during the war. Due to urgent requests for more ‘normal’ planes, he was ultimately forced to abandon his work and, besides some proposals, he never got a chance to build another such aircraft during the war. The last mention of the Bv 141 B-10 was in May of 1944, when it was used to tow another unusual design from Blohm and Voss, the experimental Bv 40 armed glider.

Operational Use

The second BV 141B prototype was allocated to Aufklärungsschule 1 (Reconnaissance Training Unit) in 1941, stationed at Grossenhain. It appears that its performance was deemed satisfactory, as more aircraft were requested in order to form at least one operational test unit for use on the Eastern Front. This was never implemented, mostly due to two reasons. The Blohm und Voss factories were redirected to higher priority projects, and since the  Fw 189 was accepted for service, there was no real need for another reconnaissance aircraft.Some sources, like the book Aircraft of World War II by C. Chant, mention that it was used in test flights over the UK and the Soviet Union during its short operational service.

Use After the War

The fate of the small number of Bv 141s produced is not known. While the majority were scrapped, some managed to survive until war’s end. One Bv 141 was actually captured by the Soviet Forces near the end of the war. This aircraft would be flight tested by the British pilot Captain Eric Brown. He was the chief test pilot of the Royal Aircraft Establishment at Farnborough. He was involved in a British project tasked with taking over German war research installations and interrogating technical personnel after the war.

The single Bv 141 was relocated to an auxiliary airfield near the town of Meissen. When Captain Brown arrived, Soviet soldiers were already taking anything that was of use from the airfield and destroying everything else. After making a request to the Soviets to see if the aircraft could be flown, the Soviets approved. He was instructed to conduct a short flight around the airfield, and to beware of possible engine malfunctions due to the general poor state of the aircraft.

Captain Eric Brown described the flight with the Bv 141 as follows. “With the flaps set to start, there was surprisingly little take-off swing, although I had expected rather a lot. The run was short, but I found the undercarriage took a long time to retract, although I suspected the hydraulics were sluggish after a long period of disuse.

The climb was mediocre at a speed of 189 km/h (112 mph) and, remembering my Russian instructions, I did not go above about 915 m (3,000 ft). Cruising speed at that height was 325 km/h (202 mph). It was at this speed that I decided to try out the theory behind the asymmetric layout of the 141, namely that in the event of attack, the aircraft could be stood on its wing tip and held there in straight flight, thus giving the gunner in the cone of the nacelles a tremendous field of fire. 

Frankly, I was sceptical of this claim of edge-on straight flight, but it proved to be, as near as damn it, true. I then stepped up the power, increasing the speed to 360 km/h (224 mph), but just as I rolled the aircraft on to its port side, the engine suddenly backfired heavily and oil pressure began to drop. This terminated any short handling session, as I considered discretion better than providing the Russians with their eagerly awaited spectacle. 

I therefore turned straight into the landing pattern with the engine throttled well back, and lowered the undercarriage immediately at about 610 m (2,000 ft) to give it time to lower in case it got temperamental. I had both flaps and the undercarriage lowered by about 305 m (1,000 ft), across wind of the final approach, turning on to finals at 150 m (490 ft) at 145 km/h (90 mph) and easing the speed off to 130 km/h (80 mph) over the airfield boundary. 

I stopped the engine at the end of the landing run, as it was obviously very sick. …. In retrospect, I am really glad to have had the unique opportunity of even a short flight in the Bv 141B, because it left me with the realisation that it was not as bad an aircraft as its development history seemed to suggest. It had good, effective controls, although it had poor lateral stability, which would have made it unpleasant to fly in turbulence at low level. Maybe this and the fact that its competitor, the Fw 189, had excellent flying characteristics, were the real reasons for its demise before reaching operational production.  “

Allegedly, according to some internet sources, at least one Bv 141 was captured by the British forces. It was then shipped to England for evaluation, but its fate is unknown.

Production

How many Bv 141s were produced is not clear in the sources. The number ranges from 13 to 18 aircraft being built. This includes at least three prototypes, five of the slightly improved A series and some 10 B series aircraft. The last Bv 141B was delivered in mid-May 1943.

• Ha 141 Prototype – The first prototype was built as a Blohm & Voss private venture.
• BV 141A –  Slightly improved version.
• BV 141B – Powered by a much stronger engine and with many other modifications, especially to the wing design.

Operators

• Germany – A few aircraft were used experimentally by the Luftwaffe.
• Soviet Union – After the War, the Soviets managed to capture one Bv 141B, but its fate is unknown.
• United Kingdom – Possibly captured one, which was allegedly shipped to England for evaluation.

Conclusion

The BV 141 initially demonstrated generally good flight characteristics, despite its unusual and radical design. The desire to further improve the flight performance, and distrust by the Luftwaffe eventually killed the project. The extensive redesign of the Bv 141B series simply had too many problems that were never completely resolved. The Luftwaffe was also reluctant to invest more time in it, especially as the more orthodox Fw 189 was being introduced into service. In the end, while it was not put into production, the BV 141 was nevertheless an interesting design and certainly deserves a spot in aviation history.

Bv 141B Specifications
Wingspans	57  ft 3  in / 17.56  m
Length	45  ft 9 in / 13.9 m
Height	11 ft 9 in  / 3.6  m
Wing Area	570 ft² / 52.9 m²
Engine	One BMW 801 A-0 1.560 HP 14 cylinder radial engine
Empty Weight	10,360  lbs / 4,700 kg
Maximum Takeoff Weight	13,450 lbs / 6,100 kg
Fuel Capacity	470 l
Climb Rate to 6 km	In 8 minute 48 second
Maximum Speed at 5.000 m	272 mph / 438 km/h
Cruising speed	250 mph  / 400km/h
Range	745  miles / 1,200 km
Maximum Service Ceiling	32,810 ft / 10,000 m
Crew	Pilot, observer and the rear gunner.
Armament	Two forward fixed 0.3 in (7.92 mm) machine guns and one same caliber machine gun placed to the rear. Up to four 110 lb (50 kg) bombs

Gallery

Illustrations by Ed Jackson

Credits

• D. Nešić (2008), Naoružanje Drugog Svetskog Rata Nemačka Beograd
• B.Eric (1977/2010) Wings Of The Luftwaffe Flying The Captured German Aircraft of World War II, Hikoki Publications.
• C. Chant (2007) Pocket Guide Aircraft Of World War II, Grange Books.
• M. Griehl (2012) X-Planes German Luftwaffe Prototypes 1930-1945, Frontline Book.
• Jean-Denis G.G. Lepage Aircraft Of The Luftwaffe 1935-1945, McFarland and Company.
• D. Donald (1994) Warplanes Of The Luftwaffe, Barnes and Noble.

Yugoslavia (1933-1947) Training aircraft – 81 Built

The FP-2 was designed as an advanced two seater biplane trainer for the Yugoslav Royal Air Force in late 30s. It would be used to equip pilot training schools for some years before WW2. During World War II, it would be used by the Axis powers, which managed to capture a number of them, for limited ground attack operations. The FP-2 would survive the war in smaller numbers and remain in use up to 1947.

History

As the Yugoslav Royal Air Force began to develop and acquire more modern types of aircraft, the need for advanced training aircraft became apparent. Due to the obsolescence of older trainers, the Yugoslav Royal Air Force Command issued orders to begin developing a new series of advanced trainers in 1933. One of the designs submitted was the Fizir FP-1 biplane made by Zmaj. Despite its disappointing overall performance, a new design was desperately needed. At the same time, a design team composed of Rudolf Fizir and Dušan Stankov began working on a new model named FP-2. In a later address to Zmaj management in May of 1940, Dušan Stankov wrote that he was responsible for the design of the FP-2, with little to no input from Rudolf Fizir. While the Royal Air Force command was more in favor of a monoplane design, the FP-2 nevertheless received a green light.

Name

The capital letters in the name FP-2 are an abbreviation for “Fizir Prelazni 2” (Физир Прелазни ФП-2). Depending on the source, it is also sometimes identified as F.P.2. During its operational service in the Yugoslav Royal Air Force, it was also known as F.P.2-K7 after its engine name, or Fizir-Stankov F.P.2 after its designers. This article will use the FP-2 designation, as it is best known today.

What is interesting is that the FP-2 name may suggest that it was an improved version of the earlier FP-1. In reality, these two projects had nothing in common. This name was done mainly for administrative reasons, in order to obtain the funds allocated for FP-1.

Work on the Prototype

Work on the first prototype began in early 1933. At this time, the Yugoslav Royal Air Force officials were negotiating with the French for licenced production of several Gnome-Rhone engine designs, including the K-7, K-9 and K-14. For this reason, it was decided to test the performance of these engines by installing them into several prototype aircraft. This decision included the FP-2 ,which was to be powered by a French Gnome-Rhone K-7, making 420 hp.

The first prototype was officially completed by the end of 1933. It was flight tested by Zmaj test pilot Pavle Bauer. The pilot performed a series of test flights without any problems. As the first flights were successful, the FP-2 was given to the Yugoslav Royal Air Force for further testing in early 1934. For the testing of the FP-2, a commission of seven members was tasked with determining its exact flight performance. The test flight series began on the 19th of February, and after only four days a preliminary report was submitted to the Yugoslav Royal Air Force Command. The report gave mostly positive remarks on the FP-2 performance, with a few changes requested, such as increasing of the fuel load, a better position for the instruments inside the cockpit, modifications of the seats etc. The K-7 engine performance was deemed sufficient, and it was also noted that the testing of the FP-2 with any other engines at the moment was not required. This commission also urged for the FP-2 to be put into production as soon as possible.

The FP-2 design team expected that a production order was to be given shortly by the Yugoslav Royal Air Force Command. But this was not the case for several reasons. The main problem was the inability of the Rakovica factory to locally produce the K-7 engine by 1936.  Due to high prices, the Yugoslav Royal Air Force could not buy these engines directly from France. Another issue was the adoption of the new Rogožarski ‘PVT’ high-wing training aircraft which used the same engine and offered better performance than the FP-2.

In order to solve this problem, the Zmaj engineers decided to replace the K-7 with the nine-cylinder Valter Pollux II (320 hp) engine. The ensuing flight tests carried out showed that the new engine only worsened the flight performance of the FP-2, due to lower power output. Thus, Zmaj was forced to replace it with the original K-7.

From the end of October to the first half of November 1934, more tests were carried out on the FP-2 with the K-7 by a second commission. This new commission had six members and was tasked with FP-2’s overall performance more thoroughly. These tests also included the testing of a few different types of propellers. The results showed that the metal type propellers gave better performance. In addition, the operational radius was evaluated and the results showed that, at the speed of 100 mph (161 km/h), the FP-2 could stay operational for three hours. Several pilots flight tested the FP-2 and, in general, positive remarks were given about its performance. The changes in the cockpit instrument arrangement was also rated as an improvement. After the tests were completed, this commission gave positive reviews for the FP-2 and suggested that it should be adopted for production as a basic trainer, but not as a fighter trainer due to the lack of performance for this role.

Technical Characteristics

The FP-2 was designed as a single-engine, two-seater basic trainer biplane. The FP-2 was made using wood as its main construction material and then covered with canvas. Its wooden elements were connected using metal pleats and rivets. The fuselage consisted of 16 oval shaped frames that were all connected with four long wooden spars. The wing’s construction was made of wood and then covered with fabric. Rear tail unit was made using a combination of metal and wood, which was then covered in  fabric. The landing gear was a fixed design with two wheels equipped with shock absorbers. There was no rear tail wheel and instead used a small skid which also was provided with a shock absorber. In winter, the front wheels could be replaced with skis.

It was powered by the French K-7 Gnome-Rhone 313 kW (420 hp) engine. The engine itself was placed on a ring shaped housing made of metal and duralumin construction. The maximum speed achieved with this engine was 148 mph (238 km/h). Being designed as a trainer aircraft, its crew consisted of a pilot/instructor and the student.

In Service Before War

For its service in the Yugoslav Royal Air Force, the first prototype was purchased for 577,000 Dinars in 1934. Next year, the contract for the construction of the first batch of 20 aircraft was signed. These were to be produced and given to basic training schools by 1936. All 20 aircraft were completed on time and were given to the First and Second basic training Schools. A few were temporarily given to the Fighter plane school until the more advanced PVT could be built. Once the PVT was adopted for service, the fighter school FP-2s were given to the basic training schools.

The FP-2 was mainly used to replace older training aircraft models that were in service. In its intended role, the FP-2 proved to have satisfactory performance and generally fulfilled the role of a basic trainer successfully. Only one accident was reported in 1938, when, due to a pilot error, control of the plane was lost and it crashed to the ground. The pilot managed to jump out of the plane and safely landed.

During the production run, there were only minor modifications between the different planes. The FP-2 which were built in 1939 were modified with improved control panels with more updated instrumentation. Zmaj also proposed a modified FP-2H powered by the K-9 engine for use by the navy, but it was not adopted.By March 1941, around 9 FP-2 aircraft were reportedly awaiting repairs at the Zmaj factory. The fifth batch of 15 FP-2 were to be built by mid-1941. The materials and engine were assembled but, due to the outbreak of the war, none were delivered to the Yugoslav Air Force. Production of the FP-2 was carried out until the Axis invasion of Yugoslavia in April 1941.

During the April War

At the time of the Axis attack on Yugoslavia in April 1941, all FP-2 were still assigned to the two basic training schools. The First pilot school was transferred near Sarajevo shortly before the outbreak of the war, along with 10 FP-2. The school was operational until the German capture of Sarajevo. The commander of this school, Colonel Adalbert Rogulja, ordered the entire unit to surrender to the Germans without attempting to sabotage its aircraft.

The Second pilot school, located at the Kapino polje near Nikšić, had 15 FP-2. As the area was not  attacked by Axis forces, this school was operational until the end of war. The remaining FP-2s were stationed in smaller numbers across Yugoslavia. One was destroyed by the Germans in Novi Sad, and a few more in Niš and Pančevo. By the war’s end, both the Germans and Italians managed to capture an unknown number of FP-2s.

In German Service

The Germans managed to capture the Zmaj factory and an unknown number (possibly more than 15) of FP-2 across Yugoslavia. But they were more interested in the factory itself than the FP-2, and for this reason did not use the aircraft that were captured.

In Italian Service

The Italians managed to capture around 13 fully operational FP-2. One was transported to Italy to be flight tested with other captured Yugoslav aircraft (Do-17K and Hurricane) in early June 1941. The remaining 12 FP-2s were stationed at Tirana, but then repositioned in May 1941 to Shkodër to join the 5° Gruppo, which was part of the 39ª Squadriglia. This unit was equipped with older IMAM Ro-37 aircraft. As these were prone to malfunction, the Italians simply reused the FP-2 and pressed them into service. They were mainly used for liaison missions between Tirana and Shkodër. But Partisan activity began to increase in the area and faced with a lack of any other aircraft, the Italians began to arm the FP-2s. The FP-2s were armed with machine guns taken from the Ro-37 aircraft.

The 39ª Squadriglia would be operational until June 1943 in the Shkodër region. It was then returned to Italy and, while it is not clear, there is a chance that at least three FP-2 were still operational with this unit. The final fate of the FP-2s in Italian service is unfortunately not known.

In NDH Service 

After the April War ended, the Germans captured all surviving aircraft production factories, including Zmaj, in Yugoslavia. They restarted production for their own needs. The newly formed NDH (Independent State of Croatia) puppet state asked the Germans for a number of aircraft for their newly formed air force. This included any available Yugoslavian aircraft that survived the war. The Germans supplied the NDH with FP-2s captured in Sarajevo during the war.

In the case of the FP-2s at the Zmaj factory, there were engines and parts for the incomplete fifth production series that could potentially be built. The Germans delayed any decision whether to allow the NDH to take these aircraft. In 1943, an arrangement was reached between the NDH Aviation Force officials and the representatives of Zmaj for the delivery of the 15 FP-2 aircraft. The production process was slow due to the lack of a qualified workforce and constant sabotage by resistance movements. By 1944, only eight FP-2s were completed for the NDH. The remaining seven would remain in Zmaj factory hangars until they were captured by the victorious Communist Partisan forces in October 1944.

During the war, the NDH Air Force used the FP-2 in its original role of a training aircraft. As the Partisan activity began to rise, some FP-2s were modified by adding bomb racks for six 12 kg (27 lb) bombs. These were then used to fight the Partisans, but as neither the pilot nor the observer were supplied with parachutes, these operations were dangerous.

By 1944, it was obvious that the Axis were on the losing side and, for this reason, many NDH pilots tried to escape to the Partisan side whenever it was possible. One of them was Mitar Оbućanin. While flying an FP-2 (6822) in late August 1944, he escaped to the Partisan held island of Vis. This plane would be used by the Partisans for reconnaissance and liaison. Another attempt was made in October by pilot Drago Markotić and assistant Milan Aćimović. The escape failed and the plane was shot down by German AA ground fire. The pilot was captured and executed but his assistant managed to escape.

The NDH had around 23 FP-2s in their Air Force. The aircraft supplied by the Germans received serial numbers 6801 to 6815 and the ones acquired from Zmaj were 6816 to 6823.

After War Service

With the liberation of Zemun, where the Zmaj factory was located, seven incomplete FP-2s were found abandoned. By late April 1945, two FP-2s were completed and put to use by the new Communist Yugoslav Air Force. The last five were completed by mid 1945. In total, around 13 were operated by the Yugoslav Air Force after the war. They would not remain long in service due to a lack of spare parts. They were mostly used as a target tug to haul flying targets for ground AA crew training.

The parts of one FP-2 can now be seen at the Belgrade Aviation Museum near the Nikola Tesla Airport.

Production

The FP-2 was produced in several batches from 1934 to 1940. The first batch consisted of 20 aircraft, followed by a second one with 15 planes in 1937, another 15 planes in 1939, and the final batch of 15 in 1940. An additional 15 planes were to be built in 1941, but due to the outbreak of the war, this was never completed.

Before the war, the total production number of FP-2s made by Zmaj was 65 aircraft, plus the prototype. During the war and, in small numbers, after the war, an additional 15 were built. In total, 81 FP-2 were built.

Modifications

• FP-2 – Main production version
• FP-2H – A proposed naval version powered by the K-9 engine, but not adopted for service.

Operators

• Kingdom of Yugoslavia – Used some 66 planes for pilot training.
• SFR Yugoslavia – After the war used seven aircraft of this type. They were all captured at the Zmaj factory. These planes were designed for the NDH but never delivered on time.
• NDH – A dozen aircraft of this type were delivered to the Air Force of the NDH in 1941 by the Germans. In 1944, another eight aircraft were delivered from the Zmaj factory in Zemun.
• Italy – Used 13 captured planes from May 1941 to June 1943 against the rebels in Montenegro and Albania.
• Germany – Captured smaller numbers of FP-2s but did not use them.

FP-2 Specifications
Wingspan	35 ft 5 in / 10.8 m
Length	25 ft  11 in /  7.9 m
Height	9 ft 6 in / 2.9 m
Wing Area	310 sq ft / 28.8 m²
Engine	One Gnome-Rhone 7K, 7-cylinder radial, 313kW (420 hp) engine
Empty Weight	1.630  lbs / 740 kg
Maximum Takeoff Weight	3.170 lbs / 1,450 kg
Maximum Speed	148 mph / 238 km/h
Cruise speed:	124 mph / 200 km/h
Effective range	360 mi / 580 km
Maximum Service Ceiling	22,300 ft / 6,800 m
Crew	Two (Instructor and student)
Armament	None

Gallery

Illustrations by Carpaticus

Credits

• Article by Marko P.
• Edited by Stan L. and Ed J.
• Illustrations by Carpaticus
• Č. Janić i O. petrović (2011) Kratka Istorija Vazduhoplovstva U Srbiji, AEROKOMUNIKACIJE Beograd.
• D.Babac (2008), Elitni Vidovi Jugoslovenske Vojske U Aprilskom Ratu, Publish.
• Vojislav V. Mikić (2000) Zrakoplovstvo Nezavisne Države Hrvatske 1941-1945, Vojno  istorijski institut Vojske Jugoslavije
• Vojislav V. Mikić (1998) Italijanska Avijacija u Jugoslaviji 1941-1943, Vojno  istorijski institut Vojske Jugoslavije
• B. Nadoveza and N. Đokić (2014), Odbrambena Privreda Kraljevine Jugoslavije, Metafizika Beograd.
• T. Lisko and D. Čanak (1998), The Croatian Air Force In The WWII, Nacionalna i sveučilišna knjižnica, Zagreb
• F. Vrtulek (2004) Ludbrežanin Inženjer Rudolf Fizir, Podravski Zbornik.
• http://www.vazduhoplovnetradicijesrbije.rs/index.php/istorija/229-fizir-fp-2

Nazi Germany (1936) Shipborne and coastal reconnaissance aircraft – 98~118 Built

In the mid-thirties, the German Ministry of Aviation (Reichsluftfahrtministerium – RLM) tasked the Heinkel company with developing a replacement for the He 60 shipborne and reconnaissance aircraft. While Heinkel fulfilled the request by building the He 114, its overall performance was deemed insufficient for German standards.

History

During the early thirties, the He 60 was adopted for service as the main German shipborne and coastal reconnaissance aircraft. As it was considered outdated, in 1935, the RLM issued to Heinkel a request for a new shipborne and coastal reconnaissance aircraft that was to replace the He 60. The next year, two prototypes were completed. While it was originally planned to test these aircraft with the BMW 132 engine, due to lack of availability, this was not possible. The first prototype (with D-UBAM marking) made its maiden flight in September 1936. It was powered by a Daimler Benz DB-600A which gave out 900 hp. The test results of the first flight were disappointing, as it proved difficult to control on the water but also in the air. The second prototype, V2 (D-UGAT), powered by a 740 hp Jumo 210 E, made its first flight in December 1936. It was used to test the catapult launching capabilities of this aircraft. It had some modifications in comparison to the first prototype, like having a larger tail and redesigned floats. Despite some improvements, the catapult launch testings from the Gneisenau showed that the He 114 was not suited for this role.

Despite not having a promising start, further prototypes were ordered. The V3 (D-IDEG) prototype was powered by an 880 hp BMW 132 K (or D, depending on the source) engine. The floats were once again redesigned and the pilot had a better-glazed shield. This aircraft was tested in April 1937 with similar performance as previous versions.

V4 (D-IHDG) made its maiden test flight in August 1937. It had many modifications in order to improve its performance. The wing’s edges were redesigned, new floats were used and it was also fitted with machine gun armament. V5 (D-IQRS) had new improved floats which enabled it to take-off even from ice. While most sources mention only five prototypes, some note that there were two more. The V6 and V7 prototypes were tested with similar equipment and were armed with two machine guns, one firing through the propeller and the second mounted to the rear. Additional armament tested consisted of two 50 kg (110 lb) bombs.

Technical characteristics

The He 114 was designed as a single-engine, all-metal, twin crew biplane aircraft. It had a monocoque oval-shaped fuselage design. It was powered by one BMW 132K 960 hp nine-cylinder radial engine. The fuel load consisted of 640 l.

Somewhat unusual for biplanes of the era, the lower wings were much smaller than the upper ones. They had a half-elliptical design and were thicker than the upper wings. The upper wing was connected to the fuselage by two ‘N’ shaped struts. There were also two ‘Y’ struts connecting the lower and the upper wings. The upper wing was constructed using three parts with two ailerons. The upper wing could, if needed, be folded to the rear. The landing gear consisted of two floats which could also act as auxiliary fuel storage tanks with 470 l each.

The crew consisted of the pilot and the rear positioned machine gunner/observer. The armament consisted of one MG 15 7.92 mm (0.31 in) machine gun placed to the rear. The ammunition load for this machine gun was 600 rounds. Additionally, there was an option to externally mount two 50 kg (110 lb) bombs.

Further development

Despite being shown to have poor performance, a small production run was made by Heinkel. Some 10 (or 6 depending on the source) aircraft of the A-0 series, together with 33 of the A-1 series would be built. The only difference was the use of a larger rear tail design on the He 114A-1 series. The small number of He 114 built were given to various test units and flight schools, where its performance was often criticized by all. During its introduction to service, the much more promising Ar-196 was under development, but it would need some time until production was possible. As a temporary solution, the Luftwaffe officials decided not to retire the He 60 from service yet. Heinkel was informed that, due to the He 114’s overall poor performance, it would not be accepted for service and that it would be offered for export if anyone was interested. For this reason, Heinkel developed the He 114A-2 series. The He 114A-2 had a reinforced fuselage, floats that could be used as fuel storage tanks, and, additionally, it was modified to have catapult attach points. The He 114A-2, while tested, was not operated by the Luftwaffe, and it was used for the export market.

The following B-series (including B-1 and B-2) were actually just A-2 planes with some slight improvements, meant primarily for export. The history of the C-series is somewhat unclear, as it appears to be specially developed for Romania. It was much better armed, with either two 20 mm (0.78 in ) MG 151 cannons, two 13 mm (0.51 in) MG 131 heavy machine guns, or even two MG 17 7.92 mm (0.31 in) (the sources are not clear) placed inside the lower wings. Some sources also mention that additional machine guns were installed inside the engine compartment and could be fired through the propeller. Additionally, it appears that its fuselage was modified to be able to carry two additional 50 kg (110 lb) bombs. The rear positioned MG 15 was unchanged. This version also had a new Junkers type 3.5 m diameter propeller. The floaters were also slightly redesigned and it received smoke screen trovers. Additionally, to provide better stability while positioned near shore, a small anchor could be realized.

Operational use

Despite not being accepted by the Luftwaffe, due to the Kriegsmarine’s (German war navy) lack of sufficient seaplanes, some He 114 had to be used for this purpose. The distribution of the He 114 began in 1938 when the 1./Küstenfliegergruppe 506 was equipped with this aircraft. In 1939, it was 43equipped with the older He 60, as these proved to be better aircraft. Some German ships, like the Atlantis, Widder, and Pinguin, received these aircraft. During their use, the He 114 floater units proved to be prone to malfunctions. These were reported to be too fragile and could easily be broken down during take-off from the sea during bad weather.

A group of 12 He 114 C-1 aircraft that were to be sold to Romania were temporarily allocated to the 2nd Squadron of the 125th Reconnaissance Group (2/125 Aufkl.Sta.). These units operated in the area of Finland’s shore. When the Bv 138 became available in sufficient numbers, the He 114 C-1 was finally given to Romania.

Foreign use

While the He 114 failed to get any large production orders in Germany, it did see some export success. These included Denmark, Spain, Romania and Sweden. The B-series was sold, which was more or less a copy of the A-2 series.

In Danish service

The Danish use of the He 114 is not clear. Depending on the source, there are two versions. In the first, Denmark managed to buy 4 He 114 aircraft and even ordered more, but the German occupation stopped any further orders. In the second, while Denmark wanted to buy some He 114, nothing came of it, once again due to German occupation.

In Spanish service

During 1942, Spain obtained some 4 He 114s from the Germans. In Spanish service, these were known as HR-4. Despite their obsolescence and lack of spare parts, these would remain in use up to 1953.

In Romanian service

Romania received a group of 12 He 114 in 1939. During the war, the number would be increased to 29 in total. These would be extensively used to patrol the Black Sea. At the end of the war, these were captured by the Soviets, who confiscated them. Some would be returned to Romania in 1947, which would continue to use them up to 1960, when they were scrapped.

In Swedish service

Sweden bought some 12 He 114 in March 1941. In Swedish service, these would be renamed to S-12. Despite being an unimpressive design and prone to malfunction, the Swedish used them extensively during the period of 1941 to 1942, with over 2054 flight missions. They would remain in service up to 1945, with six aircraft being lost in accidents.

Production

Despite its poor performance, Heinkel undertook a small production of the He 114. The number of produced aircraft ranges from 98 to 118 depending on the source.

• He 114 Prototypes – Between 5 to 7 prototypes were built
• He 114 A – Limited production series
• He 114 B – Export version of the A-series
• He 114 C – Slightly improved version with stronger armament

Operators

• Germany – Small numbers of these aircraft were operated by the Luftwaffe and Kriegsmarine, but their use was limited
• Denmark – Possibly operated four He 114 before the German occupation
• Spain – Bought four He 114, and operated them up to 1953
• Sweden – Bought 12 He 114 in March 1941, which remained in use until 1945
• Romania – Operated 29 He 114, with the last aircraft being scrapped in 1960

Surviving aircraft

While there are no complete surviving He 114s various parts and wrecks have been found over the years. Parts of one wreck were found in lake Siutghiol near Mamaia, on the Romanian Black Sea coast, in 2012. There is a possibility that the wreck of another lays in a lake near Alexeni as well.

Conclusion

The He 114 was an unsuccessful design that failed to gain any larger production orders in Germany. It had difficult controls both in the air and on the water. While it would see some limited service with the Luftwaffe, most would be sold abroad, where some were used up to the ’60s.

Specifications –  He 114A
Wingspan	44 ft 7 in / 13.6 m
Length	38 ft 2 in / 11.65 m
Height	17 ft 2 in / 5.23 m
Wing Area	455 ft² / 42.27 m²
Engine	One BMW 132K 960 hp nine-cylinder radial engine
Empty Weight	5.070 lb / 2.300 kg
Maximum Takeoff Weight	8.090 lb / 3.760 kg
Fuel Capacity	640 liters
Climb Rate to 1 km	In 4 minute 20 second
Maximum Speed	208 mph / 335 km/h
Range	572 mi / 920 km
Maximum Service Ceiling	16,075 ft / 4,900 m
Crew	One pilot and one rear gunner
Armament	One rear-mounted 0.31 in (7.92 mm) machine gun Two 110 lb (50 kg) bombs

Gallery

Illustrations by Ed Jackson

Sources

• D. Nešić (2008), Naoružanje Drugog Svetskog Rata Nemačka Beograd
• M. Griehl (2012) X-Planes German Luftwaffe Prototypes 1930-1945, Frontline Book.
• S. Lonescu and C. Craciunoi, He 114, Editura Modelism
• Jean-Denis G.G. Lepage Aircraft Of The Luftwaffe 1935-1945, McFarland and Company.
• Ferenc A. and P. Dancey (1998) German Aircraft Industry And Production 1933-1945. Airlife England. https://www.cugetliber.ro/stiri-eveniment-hidroavion-din-al-doilea-razboi-mondial-descoperit-in-lacul-tasaul-201060