Tag Archives: Yugoslavia

MS 406 in Croatian Service

Independent State of Croatia flag Independent State of Croatia (1943-1945)
Fighter –  36 to 46 Operated

During the Second World War, the German puppet state the Nezavisna Država Hrvatska NDH (Eng. Independent State of Croatia), tried to develop its own Air Force. Unfortunately for them, its German and Italian allies simply did not have the industrial resources, nor spare planes to allow them to build a significant air force. Still, the NDH’s persistence in asking for such equipment paid off in 1944 when they received over 30 captured French MS 406 fighters.

The Morane-Saulnier MS 406 in NDH service. Source: T. Likso and Danko Č. The Croatian Air Force In The Second World War

History

After Italy’s unsuccessful invasion of Greece, Benito Mussolini was forced to ask his German ally for help. Adolf Hitler agreed to assist, fearing that a possible Allied attack through the Balkans would reach Romania and its vital oil fields. In the path of the German advance towards Greece stood Yugoslavia, whose government initially agreed to join the Axis side. This agreement was short-lived, as the Yugoslav government was overthrown by an anti-Axis pro-Allied military coup at the end of March 1941. Hitler immediately gave an order for the preparation of the invasion of Yugoslavia. The war that began on 6th April 1941, sometimes called the April War, was a short one and ended with a Yugoslav defeat, and the division of its territory between the Axis powers.

With the collapse of the Kingdom of Yugoslavia, Croatia, with German aid, was finally able to declare independence, albeit becoming a fascist puppet state. It was officially formed on the 10th of April 1941. The new state received a significant territorial expansion by annexing most of western Yugoslavia, including Bosnia, parts of Serbia, and Montenegro.

While the conquest of the Kingdom of Yugoslavia proved to be an easy task for the Axis, holding these territories proved to be much more difficult. This was mainly due to two resistance movements that were actively engaged in sabotage, destroying railways and bridges, and attacking isolated occupation units’ positions and strong points. Despite attempts to suppress these attacks, the resistance movements, especially the Communist Partisans, grew rapidly, forcing the Germans and their Allies to introduce ever-larger occupation forces. The NDH forces were especially targeted as they committed mass murders and deportations to concentration camps. Thanks to the German help, they managed to form a small Air Force that in its inventory consisted of all kinds of obsolete, and in rarer cases, new equipment. By 1943, it was in the process of reorganization and the NDH officials during this time often asked their German overlords for more modern aircraft. Sometimes they even portrayed their own Air Force as weaker than it was.

The NDH Air Force was particularly poorly equipped with fighter aircraft. Luckily for them, the Germans at that time occupied what remained of Vichy France, capturing all kinds of military equipment. This also included the MS 406 fighters which was agreed to be sent to NDH by the end of 1943.

A Brief MS 406  History

At the start of the Second World War, the Morane-Saulnier MS 406 was one of the more modern French fighters built using metal components whose development began in mid-1930s. The first prototype under the designation MS 405 made its maiden test flight on the 8th of August 1935. Following successful testing and good performance, the French Ministry of Aviation issued a request for the first 50 aircraft in February 1938. Given the rising tension in Europe at that time the order was eventually increased to an additional 825 aircraft to be built. By the time, the French surrendered to the Germans over 1,000 aircraft of this type were built.

French Morane-Saulnier MS 406 fighter. Source: Wiki

The MS 406 was a good design that was nearly equal to the German Bf 109 models near the start of the war. During the War with the Germans in 1940, the MS 406 managed to achieve some success against the Germans but ultimately proved incapable of stopping the enemy. Some 300 aircraft of this type would be lost during this brief war, either due to the action of enemy fighters, ground anti-aircraft fire, or accidents. The MS 406 also achieved some success on the foreign market with 12 being sold to China, 30 to Finland, and the Swiss obtained a license for production. Poland also expressed interest in acquiring 150 aircraft of this type but nothing came of this as a result of the German invasion that began in September 1939.

In NDH service

The precise number of available MS 406 or the date when they arrived is not clear.  According to A. Pelletier ( French Fighters Of World War II in Action) the NDH received 46 MS 406 in early 1943. Author V. V. Mikić ( Zrakoplovstvo Nezavisne Države Hrvatske 1941-1945) on the other hand mentioned a lower number of 38 which began to arrive at the end of 1943 and early 1944. These aircraft received registration numbers from 2301 to 2338.  According to T. Likso and D. Čanak (The Croatian Air Force In Second World War) between 36 to 38 were sent to the NDH during 1944.

In late 1943, these aircraft, together with Italian-supplied Fiat G.50s, were to be used to equip the 11th Group consisting of three squadrons (21st, 22nd, and 23rd). The MS 406s were expected to arrive at the start of 1944. The first operational units were to be formed by mid-February. To help train the pilots, one Seiman 200 and ex-Yugoslav P.V.T aircraft were to be supplied. The training operations were carried out at Lučko airfield, starting from October 1943.

Once in Croatia, the MS 406 was used together with the Fiat G.50 fighter aircraft. Source: Wiki

The situation in the air and the ground significantly worsened for NDH at the start of 1944. It was especially hard-pressed as the Allies began bombing operations in occupied Yugoslavia. Thanks to their advances in Italy, they managed to set up many air bases from which these attacks could be launched. They bombed many military installations including ammunition depots, fuel production facilities, and NDH airfields.

An NDH MS 406 w heavily damaged during one of many Allied bombing attacks. The aircraft while damaged beyond repair was not written off, as it was used to cannibalize any usable spare parts. Source: T. Likso and D. Čanak The Croatian Air Force In The Second World War

On the 5th or 6th of April 1944, the Lazužani airfield where the NDH 5th Air  Base was located was bombed by the Allied 2nd SAAF Squadron. They managed to completely destroy 11 and damage 20 more aircraft. One MS 406 was destroyed when an Allied bomb landed next to it. The pilot Cvitan Galić did not survive the explosion. The loss in material was such that the 23rd Lovačko Jato was disbanded. Another MS 406 was lost during a second Allied bombing run on Borongaj and Lučko air bases that occurred on the 12th of April 1944.

In March 1944 Hrvatska Zrakoplovna Legija HZL (Eng. Croatian Air Force Legion) arrived at the NDH capital Zagreb. This unit was formed way back in 1941 and was in direct control by the Germans. Its pilots participated under German controls on the Eastern Front and were quite experienced. The Germans demanded that at least two MS 406s be given to this unit to be used as training aircraft. The NDH officials could do little not to comply.

By 15th September 1944, there were 19 available MS 406 aircraft. Of this number only 7 were fully operational. On September 18th, or on the night of the 21st the sources are not clear, the Partisan forces managed to capture an NDH airfield near Banja Luka. Some 30 ,or 11 depending on the source, aircraft stationed there were captured. The NDH personnel either joined the Partisans or fled leaving behind valuable equipment and supplies. The Partisans managed to capture 3 MS 406 fighters, two were under repair. These were used against their former owners, but one was damaged in an accident and was written off.

In late 1944, the few surviving MS 406 were used in desperate attempts to stop the victorious Partisans forces that were liberating Yugoslavia from the Axis occupiers. By this point, the NDH Air Force could do little to stop them given the chronic lack of fuel. Unfortunately, the precise information about the fate of many NDH aircraft in the last few months of the war was not recorded well. While the Partisans managed to capture a few MS 406 their use was limited at best, and unfortunately, none of them is known to have survived the war.

An MS 406duirng the winter of 1944. Source: T. Likso and D. Čanak The Croatian Air Force In The Second World War

Camo and markings

The MS 406 appears to have been left in German late time war type camouflage. This usually consisted of  Dunkelgrun (Eng. Dark green) and Grau  (Eng. Grey) on the upper aircraft surfaces, and  Hellblau (Eng. Sky Blue) on the lower surfaces. A standard Croatian white and red checkerboard coat of arms was painted on the wings and the fuselage sides. Starting from 24th February 1945 the NDH Air Force introduced the use of a black trefoil that was painted on the aircraft fuselage sides.

Near the end of the war, the NDH Air Force introduced the use of a black trefoil that was painted on the aircraft fuselage sides. Source: https://ww2aircraft.net/forum/threads/morane-saulnier-ms-406.50613/page-2

Technical Specification

The MS 406 was designed as a low-wing mix-construction fighter.  Its designers went for a conventional construction aircraft design. The fuselage frame was made using aluminum tubes connected and covered with Plymax. This is a  composite material that consists of layers of aluminum and plywood. The wings were constructed using a combination of spars and steel tubes also covered in this material. It was powered by one 860 hp Hispano-Suiza liquid-cooled engine. Most produced aircraft used a three-bladed two-pitch propeller, while some received variable-pitch propellers. The armament consisted of one 20 mm (0.78 in) Hispano-Suiza S9 cannon and two 7.5 mm (0.29 in) MAC 1934 machine guns. The cannon fired through the propeller shaft.  The total ammunition load for the cannon was 60 and for the two machine guns 600 rounds.

Conclusion

The MS 406 was one of the few more modern fighter aircraft that was available in any significant number. But despite that, it was already obsolete and could realistically do little against Allied bombers and fighters. It was mostly used to fight the advancing Partisan formations. Few remaining aircraft were used in this role up to the end of the war.

MS 406  Specifications

Wingspans 10.6 m / 34  ft 10  in
Length 8.13 m / 26 ft 9  in
Height 2.71 m / 8  ft 10  in
Wing Area 17.1 m² / 184 ft²
Engine One 860 hp Hispano-Suiza 12Y-31 liquid-cooled engine
Empty Weight 1,900 kg / 4,190  lbs
Maximum Take-off Weight 2,426 kg / 5,790  lbs
Climb Rate per minute 850 m / 2,790 ft
Maximum Speed 485 km/h / 302 mph
Range 1,000 km / 620 miles
Maximum Service Ceiling 9,400 m / 30,840 ft
Crew 1 pilot
Armament
  • One 20 mm (0.78 in) cannon and two 7.5 mm (0.29 in) machine guns

Illustration

 

Credits

  • Article written by Marko P.
  • Edited by  Henry H.
  • Illustration by Godzilla

Source:

  • A. Pelletier (2002) French Fighters Of World War II in Action, Squadron/Signal Publication
  • Duško N. (2008)  Naoružanje Drugog Svetsko Rata-Francuska. Beograd
  • V. V. Mikić, (2000) Zrakoplovstvo Nezavisne Države Hrvatske 1941-1945, Vojno  istorijski institut Vojske Jugoslavije.
  • T. Likso and Danko Č. (1998) The Croatian Air Force In The Second World War, Nacionalna Sveučilišna Zagreb
  • J. R. Smith and A. L. Kay (1990) German Aircraft of the Second World War, Putnam
  • D. Monday (2006) The Hamlyn Concise Guide To Axis Aircraft OF World War II, Bounty Books
  • T.L. Morosanu and D. A. Melinte Romanian (2010) Fighter Colours 1941-1945 MMP Books
  • D. Bernard (1996) Heinkel He 112 in Action, Signal Publication
  • R.S. Hirsch, U, Feist and H. J. Nowarra (1967) Heinkel 100, 112, Aero Publisher
  • C. Chants (2007) Aircraft of World War II, Grange Books.

 

 

 

 

He 112 in Hungarian Service

Hungarian Flag Kingdom of Hungary (1938)
Fighter Aircraft – 4 aircraft operated

Despite being not adopted for service by the German Luftwaffe, the He 112 had great potential as an export aircraft. Spain, Romania, and Japan were some of the countries that got their hands on fighter aircraft. Hungary, with its close ties to Germany, also wanted this fighter in its inventory, though it was not to be. Unfortunately for them, despite their efforts, only a few of these aircraft would ever see service with their Air Force. This was mainly due to the reluctance of Germany to provide the necessary parts and licenses, and the start of the Second World War. The few aircraft that did reach Hungary were mainly used for crew training and even saw limited combat use.

One of few He 112 in Hungarian service. Source: www.destinationsjourney.com

A brief He 112 history

Prior to the Second World War, the Luftwaffe was in need of a new and modern fighter to replace the older biplanes that were in service, such as the  Arado Ar 68 and Heinkel He 51.  For this reason, in May 1934, the RLM issued a competition for a new, modern fighter plane. While four companies responded to this request, only the designs from Heinkel and Messerschmitt were deemed sufficient. The Heinkel He 112 was a good design that offered generally acceptable flight characteristics and possessed a good foundation for further improvements. The Bf 109 on the other hand, had slightly better overall flight performance and was much simpler and cheaper to build. Given the fact that the Germans were attempting to accelerate the production of the new fighter, that alone was seen as a huge advantage over the He 112. Ultimately it would not be accepted for service, and only 100 or so aircraft would be built. These would be mainly sold abroad, with those remaining in Germany being used for various testing and evaluation purposes.

He 112 the unsuccessful competitor of the Bf 109. Source: www.luftwaffephotos.com

While the He 112 project was canceled by the RLM, to compensate for the huge investment in resources, Heinkel was permitted to export this aircraft.  A number of countries such as Austria, Japan, Romania, and Finland showed interest, but only a few actually managed to procure this aircraft, and even then, only in limited numbers.

Hungarian Interest in the He 112

Being that it was on the losing side of the First World War, the Hungarians were in a similar situation to Germany in regard to military restrictions under the Treaty of Versailles. Crucially, it prohibited the Hungarians from developing their air forces. In time though, the Allies became less and less involved in maintaining the Treaty, and the Hungarians began slowly rebuilding their air force.  By 1938 the  Magyar Királyi Honvéd Légierő MKHL (English: Royal Hungarian Home Defence Air Force) was openly presented to the world. At that time, the Hungarians undertook steps to rebuild their armed forces in the hope of reclaiming some of their lost territories. For a modern air force, they needed better fighter designs, as their aged biplanes would not be sufficient. By 1938, they had improved their relations with Germany, and it was then possible to acquire new equipment from them.

The Hungarian military delegation that was in Spain during the civil war observed the relatively new Heinkel He 112 fighter in action and immediately became interested in it. In June 1938, a military group disguised as a civilian delegation visited Heinkel’s company. Three Hungarian pilots had the chance to flight test the He 112V9 aircraft. They were highly impressed and urged the Hungarian Army officials to adopt this aircraft. Unsurprisingly, based on the glowing report, the Hadügyminisztérium (Ministry of War Affairs) asked Heinkel for 36 such aircraft.

Unfortunately for them, Heinkel never actually put the He 112 into mass production, given the fact that it was not adopted for service with the German Air Force. It did, however, build a small series that was intended for Spain and Japan. The Hungarian offer was not considered as important, and thus no aircraft would be delivered to them. The Reichsluftfahrtministerium RLM (English: German Ministry of Aviation) also intentionally delayed the delivery of weapons to Hungary. This was done to politically and economically pressure the Hungarians and Romanians who were on the brink of war at that time, in an attempt to reduce tensions.

Still, the Hungarians persisted, and at the start of 1939, they requested again for the 36 aircraft, and once again, the Germans denied this request. However, a single He 112 V9 was given to Hungary and was used for flight testing near Budapest. On the 5th of February 1939, it crashed during a test flight against a CR-32 biplane fighter.  In March 1939, another aircraft was sent to Hungary, this one being a He 112 B-1. It was extensively tested by the Hungarians who generally liked its design.

The He 112 V9 was lost in an accident during its first test flight. Source: D. Bernard Heinkel He 112 in Action

As the Romanians acquired a batch of 24 He 112 In 1939, the Hungarians were concerned over their neighbor’s growing military strength. Realizing that the Germans would not deliver the promised aircraft, they decided to ask for a production license instead. This was granted, and Heinkel also delivered two more He 112 B-1 with the Jumo 210E engine. When the license document arrived in Hungary in May 1939, a production order for the 12 first aircraft was given to the Weiss Manfréd aircraft manufacturer. Several changes were made, including the installation of 8 mm 39.M machine guns and the addition of bombing racks. In addition, the original 2 cm cannons were to be replaced by the Hungarian, domestically built, Danuvla 39, though it is unclear if any were actually installed. As the preparation for the production was underway the three available He 112 were adopted to service. This received coded designation V.301 to 303 where the V stands for Vadász (English: Fighter).

The B-series was in many aspects a complete redesign of the previous series. Including the introduction of a new tail unit, and part of the fuselage, to name a few. Source: www.luftwaffephotos.com

Despite the best Hungarian attempts to put the He 112 in production, the situation was made impossible by the coming war between Poland and Germany. The RLM would officially prohibit the export of any German aircraft engines and equipment at the start of the war. This meant that the vital delivery of the Jumo 210 and DB 601 engines could not be made. Based on this fact, all work on the Hungarian He 112 was canceled. Instead,  Weiss Manfréd investigated to see if it could reuse most of the He 112 production line to produce a new domestic design named WM–23 Ezüst Nyíl (English: Silver arrow). While one prototype was built it was lost in an accident which ended the project.

The WM–23 Ezüst Nyíl prototype. Source: www.destinationsjourney.com
The V.303 during pilot training in 1940. Source: www.destinationsjourney.com
Despite their best efforts, the Hungarians managed to operate only three He 112 (not including the single aircraft last way back in Budapest) Source: www.destinationsjourney.com

In Combat

In the Summer of 1940, the rising tension between Romania and Hungary over Transylvania reached a critical point. Transylvania was once part of Hungary but was lost after the First World War when it was given to Romania. By 1940, the Hungarian Army began preparing for a possible war with Romania over the territory. As neither side was willing to enter a hastily prepared war, negotiations began to find a possible solution. But despite this, there were some minor skirmishes, and Hungarian aircraft made several reconnaissance flights over Romania. The three Hungarian He 112 were stationed near the border, and the Romanians also had some He 112 in their inventory. While the Hungarian He 112’s did take up to the sky, no combat action by them was reported. Ultimately, at the end of August, Romania asked Germany to arbitrate the issue regarding the disputed territory, With Hungary being given the northern part of Transylvania in the settlement.

During the Axis invasion of Yugoslavia in April 1940, Hungary once again mobilized its He 112s. These were stationed near the border with Yugoslavia but they were not used in any combat operations.

By the time the Axis attacked the Soviet Union in June 1941 all three He 112 were used as training aircraft, with their secondary role being to protect the Weiss Manfréd factory. Due to a lack of spare parts, there was no point in sending this aircraft to the frontline. Two aircraft were involved in a landing accident where they were damaged. While their final fate is not completely clear, they may have been destroyed in 1944 when the Allies intensified their bombing campaign against Hungary. It is unlikely that the He 112s were operational at this point.

The V.301 had an accident where the pilot forgot to activate the landing gear. This is not surprising given that most pilots at that time mainly flaw on the older biplanes that had fixed landing gear. Source: www.destinationsjourney.com
In the Summer of 1941 the V.303 was damaged during a landing where the left landing gear wheel simply broke off. Source: www.destinationsjourney.com

Technical Characteristics

The He 112 was an all-metal, single-engine fighter. The monocoque fuselage consisted of a metal base covered by riveted stress metal sheets. The wing was slightly gulled, with the wingtips bending upward, but otherwise had a conventional construction.

During its development life, a great number of different engines were tested on the He 112. For the main production version, the He 112 B-2, it carried a 700 hp Jumo 210G liquid-cooled engine, with some others being equipped with the  680 hp Jumo 210E engine. The He 112 had a fuel capacity of 101 liters in two wing-mounted tanks, with a third 115-liter tank placed under the pilot’s seat.

The landing gear was more or less standard in design. It consisted of two larger landing wheels that retracted into the wings and one semi-retractable tail wheel. The He 112 landing gear was wide enough to provide good ground handling and stability during take-off or landing.

The cockpit received a number of modifications. Initially, it was open with a simple windshield placed in front of the pilot, with Later models having a sliding canopy.

The armament was changed throughout the He 112’s production, and the last series was equipped with two 7.92 mm MG 17 machine guns and two 2 cm MG FF cannons. The ammunition load for each machine gun was 500, with 60 rounds for each of the cannons. If needed, two bomb racks could be placed under the wings.

Conclusion

The He 112, although few in number, provided the Hungarian Air Force with one of its first modern fighter aircraft. Despite the Hungarian attempts to acquire over 30 aircraft from Germany, this was never achieved. In the end, the Hungarians only had three operational He 112, and one  was lost in an accident during testing. While these were stationed on the front line on two occasions they never saw actual combat action. By 1941 due to a lack of spare parts, they were allocated for training purposes. The Hungarians eventually got a production license for the Messerschmitt Bf 109G making the few available He 112 unnecessary.

 

He 112B-1 Specifications

Wingspans 29  ft 10  in / 9.1 m
Length 30  ft 2 in / 9.22 m
Height 12 ft 7 in  / 3.82  m
Wing Area 180  ft² / 17 m²
Engine One r 680 hp Jumo 210E  liquid-cooled engine
Empty Weight 3,570  lbs / 1,620 kg
Maximum Take-off Weight 4,960 lbs / 2,250 kg
Climb Rate to 6 km In 10 minutes
Maximum Speed 317 mph / 510 km/h
Cruising speed 300 mph / 484 km/h
Range 715 miles / 1,150 km
Maximum Service Ceiling 31,170 ft / 9,500 m
Crew 1 pilot
Armament
  • Two 20 mm (1.8 in) cannons and two machine guns 8 mm (0.31 in) machine guns and 60 kg bombs

Credits

  • Article written by Marko P.
  • Edited by  Henry H.
  • Ported by Marko P.
  • Illustrated By Godzilla

Illustrations

Source:

  • Duško N. (2008)  Naoružanje Drugog Svetsko Rata-Nemаčaka. Beograd
  • G. Punka (1994) Hungarian Air Force, Squadron Publication
  • J. R. Smith and A. L. Kay (1990) German Aircraft of the Second World War, Putnam
  • D. Monday (2006) The Hamlyn Concise Guide To Axis Aircraft OF World War II, Bounty Books
  • D. Bernard (1996) Heinkel He 112 in Action, Signal Publication
  • R.S. Hirsch, U, Feist and H. J. Nowarra (1967) Heinkel 100, 112, Aero Publisher
  • C. Chants (2007) Aircraft of World War II, Grange Books
  • S. Renner. (2016) Broken Wings The Hungarian Air Force, 1918-45, Indiana University Press

 

Ikarus IK-2

kingdom of yugoslavia flag Yugoslavia (1933)
Fighter – 2 Prototypes & 12 Production Aircraft Built

The IK-2 fighter aircraft. Source: www.vazduhoplovnetradicijesrbije.rs

During the early 1930’s, the Royal Yugoslav Army Air Force (RYAF) was mainly equipped with old and obsolete biplane fighters. The introduction of a new fighter was desirable, but its development was hampered by the resistance of leading military officials, and pilots who still believed in the superiority of the biplane. Once Ikarus commenced production of the new high-wing IK-2, it readily demonstrated its superiority over the biplanes of the prior generation.

History of Ikarus 

Ikarus was one of the first Yugoslavian domestic aircraft manufacturers. It was formed in October 1923 by a group of businessmen from the city of Novi Sad. The aircraft development department was led by Josip Mikl and Dimitrije Konjević. Josip Mikl had previously been involved in the development of hydroplanes for the Austro-Hungarian Empire during World War I, while Dimitrije Konjević was a former high-ranking officer in the Yugoslav Naval Air Force. The company saw success during the twenties and received a series of new orders for the production of aircraft, mostly for training. In 1927 thanks to increasing revenues, Ikarus opened a new production plant located in Zemun near the capital of Belgrade. It was heralded as a great success when it received a large production order for some 200 license-built Potez 25 aircraft in 1932.

Ikarus crest. Source: Wiki

The IK-2 Development

In early 1930, the main fighter of the RYAF was the aging Avia BH-33 biplane fighter. In the hopes of replacing it with a new domestically-developed fighter, two aircraft engineers from Ikarus, Ljubomir Ilić, and Kosta Sivčev began working on a new design. Interestingly this was a private venture and not ordered by the state, which was unusual.

While initially intended to be a low-wing fighter with retracting landing gear, due to fierce opposition from many Air Force officers and pilots who favored the old biplane design, this new concept had to be abandoned at an early stage of development. The two engineers then decided to proceed with a high-wing fighter design that was to be powered by a strong engine. A wooden mock-up was completed in 1933 which would be tested using a wind tunnel in Paris. After the first drawings and testing of the mock-up were completed, the result of this work was given to the RYAF officials in September 1933. After an analysis of all available data, a green light was given for the project, and Ikarus was instructed to build the first prototype.

At this early stage, the new fighter received the IK-L1 designation. As was common in Yugoslavia at the time, new aircraft designs usually received a designation based on the designer’s initials. In this case, I stand for  Ilić and K stands for Koča which was Kosta Sivčev nickname. The L1 represents L for Fighter (Lovac in Yugoslavian) and the number 1 indicates the first prototype. The first fully functional prototype was completed by September 1934.

The first prototype IK-L1 with its two designers Ljubomir Ilić and Kosta Sivčev next to it. Source: www.vazduhoplovnetradicijesrbije.rs

Testing the First Prototype

While the IK-L1 prototype was scheduled to be flight tested shortly after the first prototype was fully completed in September 1934, due to numerous delays it wasn’t conducted until April 1935. Unfortunately for the Ikarus and its design team, the first prototype had a very short and abrupt service life. As it was being prepared for the first series of test flights, an upswell of opposition, mainly from Captain Leonid Bajdak and other pilots, vehemently objected to the introduction of such a radical new design, arguing that the biplanes were superior. Regardless, Bajdak was chosen to fly test the IK-L1 prototype.

The maiden flight was made on the 22nd of April, 1935 at an airfield near Belgrade in Zemun. The first day of flying was rather successful, with the prototype exhibiting generally good performance. The test the following day produced largely similar results, but upon landing, some of the wing’s fabric skin was noted as slightly loose. Regardless, it was agreed that the testing should carry on. On the 24th of April, while flying the prototype, Captain Bajdak performed a series of unplanned aerobatics. At a height of 1,000 meters, he made a sharp dive, followed by an abrupt climb. This of course caused massive stress on the wing, which led to part of it breaking off the aircraft. Bajdak lost control and had to bail out. While he survived without injury, the IK-L1 prototype crashed and was completely destroyed.

According to Captain Bajdak in his report, he wrote that the IK-L1 had good controls and was pleasant to fly. The most obvious issues were the lack of visibility, due to the high-wing design. Another of his objections was the long take-off of some 300 meters. This was a surprisingly fair report from a pilot who professed such serious misgivings about this new design.

Work on a New Prototype

After an analysis of the IK-L1 wreckage, it was discovered that the accident was primarily due to poor build quality. As Captain Bajdak’s report was insufficient to make a final conclusion, Ikarus officials decided to produce another prototype. This time great care was taken to ensure the overall quality of its construction. Another change made was that the aircraft was built using mostly metal construction, with the exception of the aft fuselage and tail. The second prototype was designated IK-02 and took about ten months to be built, completed in June 1936. A new test pilot was chosen, Flight Lieutenant Janko Dobnikar. The series of flight tests were carried out at the newly opened test center stationed at the Zemun airfield. Early flight tests were quite satisfactory, with the IK-02 reaching a top speed of 435 km/h.

In 1937 the IK-02 prototype was tested in a mock dogfight against the Hawker Fury, the RYAF’s then-current biplane fighter. After a series of 16 such exercises, the IK-02 easily beat the Hawker Fury in almost every category of flight performance,  speed, climb rate, and turning ability, among others. Frustrated by the success of the new fighter, Captain Bajdak and Lieutenant Dobnikar frequently got into fierce quarrels. It ended with Lieutenant Dobnikar challenging Captain Bajdak to a flight contest. The conditions of the contest were as follows: both pilots had to reach a height of 4 km over Zemun, after which they were to race a distance of 140 km from Belgrade to Novi Sad and back. The competition was meant to end in a mock dogfight between the two. Lieutenant Dobnikar IK-02 easily won the first two rounds of the race. The mock dogfight was fierce but Captain Bajdak’s Fury was constantly overtaken by the superior IK-02. In the end, he had to admit defeat and thus concede that the IK-02 had bested the biplane. Unfortunately, the IK-02 would be lost when it was hit by lightning during a flight. As the aircraft began to catch fire, the pilot bailed out. While he survived, the aircraft crashed and burned, completely destroying it.

Limited Production

Despite both prototypes being lost to separate accidents, their overall performance was deemed acceptable and a small production order was given. In November 1937 Ikarus was instructed to produce 12 IK-2 aircraft. The first six were delivered in December 1938, with the remaining aircraft arriving by February the following year. After a brief period of adjustment and training, the IK-2 was allocated to the 6th Fighter regiment stationed in Zemun. In October 1939, the IK-2 was redeployed to Zagreb and given to the 4th Fighter Regiment. Just prior to the Yugoslavian entry into World War II, the 4th Fighter Regiment would be repositioned to Bosanski Aleksandrovac close to Banja Luka. It was part of the 107th Squadron with the task of protecting the 8th Bomber Regiment, consisting of some 23 Bristol Blenheim bombers.

Despite being superior to other fighter designs that were in service with the RYAF, it too would be replaced by the later developed IK-3 fighter. Source: www.destinationsjourney.com

Technical Characteristics

The IK-2 was a high-wing, single-engine, almost all-metal fighter aircraft.  Its fuselage was constructed of a chrome-molybdenum steel tube frame which was then covered with duralumin skin. The rear section of the fuselage close to the tail unit was covered with fabric.

The semi-cantilever wings were built using the same principle as the fuselage. The difference was that the first prototype used a fabric skin. The second prototype and the production aircraft used a duralumin skin. Two larger struts were placed beneath each wing. The tail unit was of a standard design, with one horizontal and two vertical stabilizers.

Close-up view of the IK-2 wing struts construction. Source: N. Miklušev Maketar Plus

The fixed landing gear consisted of two larger wheels and a smaller tailwheel. To help during landing the front landing gear was equipped with pneumatic shock absorbers. These were also fitted with brakes. The tailwheel was steerable. Initially, the front landing wheels were covered in a protective cover, also known as ‘spats,’ which were later removed.

The cockpit was fully enclosed. Interestingly its sliding canopy actually slid down into the fuselage sides. Quite similar to those used on ordinary cars. Due to the high wing design, the pilot’s visibility was severely limited. To somewhat remedy this issue two small glass windows were placed on the cockpit fuselage sides to help during landing.

The IK-2 cockpit was fully enclosed, but its sliding canopy slides down into the fuselage sides. Source: N. Miklušev Maketar Plus
To help the pilot cope with the cockpit’s fairly limited visibility, two smaller glass windows were placed on the cockpit fuselage sides. Source: N. Miklušev Maketar Plus

The two IK-2 prototypes were powered by an 860 hp Hispano-Suiza V-12 engine. It was equipped with an adjustable pitch three-blade propeller. The fuel tanks were located just aft of the engine in front of the cockpit. The production aircraft was powered by an 860 hp Avia HS engine. This engine was built under license in Yugoslavia. Overall performance of the aircraft did not change much, as the engine swap was mainly done to facilitate ease of maintenance.

The IK-2’s armament consisted of two 7.7 cm Darne Mle 1930 machine guns, and one 20 mm Hispano HS-9 cannon. The machine gun’s ammunition load consisted of 250 rounds each, and 60 rounds for the cannon. The cannon fired through the center of the propeller shaft, while the two machine guns were placed on each side of the front of the fuselage. Some IK-2’s had their cannon replaced with a 7.92 Browning machine gun. But by the time of the war, all available aircraft were equipped with the 20 mm cannon.

According to D. Babac, the two Darne Mle 1930 machine guns were at some point replaced with two 7.92 Browning machine guns. In addition, this author notes that the machine guns were placed above the engine compartment and not on the sides.

In War

When the war broke out on the 6th April 1941 the 4th Fighter Regiment had only 8 fully operational aircraft ready for service. Four IK-2’s suffered from mechanical breakdowns and were undergoing repairs at Zemun and Zagreb workshops. Author Z. Rendulić mentioned that only 10 IK-2 were available.

Two IK-2 (With 31 and 34 white painted markings) from the 4th Fighter Regiment were taken at Borongaj airfield in Zagreb in 1940. Note the long groove for the machine gun located above the exhaust pipes. Source: N. Miklušev Maketar Plus

In addition, the 4th Regiment had 18 to 20 Hawker Hurricanes, making this unit among the most up-to-date in the RYAF. On the first day of the war, the IK-2 was mainly used for reconnaissance. The following day, two IK-2s tried to bring down a German reconnaissance aircraft but failed to do so. One IK-2 would be lost, possibly due to mechanical breakdown. The first proper combat engagement of the IK-2 occurred on the 9th of April when during reconnaissance, a group of some 23 Bf 109 were spotted.  While one IK-2 had to land to refuel, the second one provided a delayed action in hopes of giving the 4th Fighter Regiment enough time to muster its available fighters. Shortly after, some 5 or 6 IK-2 and 8 Mk.I Hurricanes joined the fight. The German fighters were attacking in well-coordinated groups, protecting each other, while the Yugoslav fighters entered the battle in a somewhat disorganized manner. After a fierce skirmish that lasted some 10 minutes, the Germans broke off and retreated back to their base of operations in Austria. The Germans lost two aircraft, while the Yugoslavians lost three, one IK-2 and two Hurricanes.  In the next few days, engagements with the enemy were rare, but the IK-2 managed to shoot down one Ju 88, in addition to two other Luftwaffe aircraft.

The 4th Regiment would meet its fate on the 14th of April when the pilots decided to destroy their remaining aircraft in order to prevent them from falling into enemy hands. Despite their attempts, the Germans managed to capture one slightly damaged IK-2 belonging to the 4th Fighter Regiment. Four additional aircraft were acquired when the repair workshops in Zagreb and Belgrade were captured.  Some internet sources noted that up to 9 aircraft were captured by the Germans, but this seems highly unlikely and that the number of 5 is probably correct.

While a number of IK-2 were lost due to mechanical failures, the majority would be destroyed by their own crews to prevent them from being captured by the Germans. Source: www.destinationsjourney.com

In NDH Service 

Following the defeat of Yugoslavia, the Independent State of Croatia, a German puppet state was created. In June 1941 a request was made to the Germans to provide over 50 captured Yugoslavian aircraft including the IK-2, in an attempt to create a Croatian Air Force. The Germans were more than willing to give the most obsolete aircraft including four IK-2. The fate of the fifth aircraft is not clear. It may have been cannibalized for spare parts, or even sent to Germany for evaluation, but due to a lack of precise sources, we can not be sure. The Croatian Air Force regularly had problems acquiring spare parts for the Yugoslavian aircraft, as these were either destroyed, sabotaged, or commandeered by the Germans. Surprisingly the IK-2 remained in service for a few years until 1944 when they were finally withdrawn from service. They were rarely used by the Croats who often complained about its poor visibility.  Sadly no IK-2 survived the war, with all likely being scrapped.

Production Versions

  • IK-L1 –  First prototype aircraft that was lost in an accident only a few days after initial trials were conducted
  • IK-02 – The second more successful prototype
  • IK-2 – Production version

Operators

  • Kingdom of Yugoslavia – Eight were used during the April War.
  • Independent State of Croatia NDH – Used four aircraft supplied by the Germans, their service was limited.

Conclusion 

The Ikarus IK-2 was one of the earliest Yugoslavian attempts to develop the first proper fighter aircraft and was intended to replace the aging biplanes then in service with the Yugoslavian Royal Air Force.  While it proved to possess superior performance to biplane fighters, it too was quickly made obsolete by the introduction of new low-wing fighter aircraft. Regardless, the IK-2 was a sound design, which proved that the Yugoslav aviation industry, despite its small size, was capable of producing a viable mono-wing fighter aircraft.

The Ikarus’ powerful engine and impressive armament paved the way for Yugoslavia’s later advanced monoplane, the IK-3. Its performance in key areas gave it an advantage over the Hawker Fury. The IK-2 saw combat against Germany’s advances in the early 1940s before it was ultimately superseded by more advanced aircraft.

IK-2 Specifications

Wingspans 11.4 m / 37 ft 4 in
Length 7.88 m / 25 ft 8 in
Height 3.84  m / 12 ft 6 in
Wing Area 18  m² / 59 ft²
Engine One 860 hp Avia HS12YCrs
Empty Weight 1.500 kg / 3.300 lbs
Maximum Takeoff Weight 1.875 kg / 4.130 lbs
Climb Rate to 5 km In 5 minute 25 seconds
Maximum Speed 450 km/h / 280 mph
Cruising speed 250 km/h / 155 mph
Range 700 km/ miles
Maximum Service Ceiling 12,000 m / 39.370 ft
Crew 1 pilot
Armament
  • Two 7.7 mm machine guns and one 2 cm cannon
Yugoslav IK-2 107 Eskadrila, 34 Grupa, 4 Lovački Puk No.2104
Yugoslav IK-2 107 Eskadrila, 34 Grupa, 4 Lovački Puk No.2108
IK-2 in NDH service

Credits

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

Sources

  • T. Likos and D. Čanak (1998) The Croatian Air Force In The Second World War, Nacionalna i Sveučilišna Knjižnica Zagreb
  • V. V. Mikić (2000) Zrakoplovstvo nezavisne države Hrvatske 1941-1945, Target Beograd
  • Č. Janić i O. Petrović (2011) Kratka istorija vazduhoplovstva u Srbiji, Aero Komunikacije
  • D.Babac Elitni vidovi Jugoslovenske vojske u Aprilskom ratu.
  • Z. Rendulić (2014) Lovačka Avijacija 1914-1945, Teovid
  • B. Dimitrijević, M. Micevski and P.  Miladinović (2016) Kraljevstvo Vayduhoplovstvo 1912-1945
  • N. Miklušev (2013) Maketar Plus, IMPS Srbija
  • http://www.vazduhoplovnetradicijesrbije.rs/index.php/istorija/565-ikarus-ik-2

 

Ikarus 453MW

Yugoslavia flag Federal People’s Republic of Yugoslavia (1952)
Experimental Glider – 1 Prototype Built

The experimental Ikarus 453MW glider. [airwar.ru]
Following the end of the Second World War, the newly created Jugoslovenska Narodna Armija JNA (Yugoslav People’s Army) initiated a series of experimental aircraft design programs. These were intended for testing and gaining valuable experience in new jet propulsion technologies. From this initial work, an unusual new glider project, designated Ikarus 453MW, would emerge. Little is known about the purpose of this glider and its defined role.

The Unusual Glider

After the war, the once-proud Yugoslavian aviation industry was in ruin. Most of its firms had been either looted or destroyed, and many of the pre-war designers and engineers had been killed by the Germans during their retreat. The Allied bombing of Belgrade also inflicted further damage to the Yugoslavian industry’s infrastructure.  However, as the Yugoslav Partisans began liberating the country, some production facilities were slowly restored, as was the case with Ikarus in late 1944. The initial steps of the revitalization effort of the shattered Yugoslavia aviation industry were undertaken in late 1945 by the newly established Yugoslavian Air Force Command. A series of aircraft design teams were set up with the aim of creating a base for the new air force.

By the early 1950’s the overall situation changed to the extent that the Yugoslavian Army officials were ready to test various new technologies and designs. During this time, the Generalna Direkcija Vazduhoplovne Industrije GDVI (Directorate General of the Aviation Industry) led by Dragoljub Bešlin produced a series of experimental aircraft intended to test new design concepts. In 1952, work on an unusual inverted gull “M” shamed wing design began. The design team was also supported by the engineer Levačić. He was an experienced designer who worked with the British Royal Air Force during the war .

In the 1950s a series of experimental aircraft were produced including (from the left to the right side) Ikarus 452-2, 451M jet aircraft, and two prone-operated aircraft the Ikarus 451 and 232  acesflyinghigh.wordpress.com

The precise reasons for its commissioning and its history are not clear, but it appears that the Yugoslav army officials wanted to test a design that could offer a small and fast ground attack aircraft. When the design was ready, Ikarus was asked to construct the first glider prototype. If the glider design proved to have merit, the next step would be to equip this aircraft with a fully functional jet engine. It was designated the Ikarus 453MW, but it is also sometimes referred to as Р-453MW or GDVI-9. To avoid confusion this article will use the Ikarus 453MW designation. The MW  designation was used as the wings highly resemble these letters.

Technical Characteristics 

The Ikarus 453MW was a single-seat, mixed-construction experimental glider. Its fuselage was made of a metal base covered with metal sheets. The wings and tail assembly were made out of wood. The most noticeable characteristic of this glider was the use of unusual inverted gull m-shaped wings. The inverted gull wing design was used during the war by famous aircraft such as the German Ju 87 Stuka Japanese Aichi B7A and the American F4U Corsair. The Ikarus 453MW wings consisted of four parts. The part where the wings folded down was separated by two round-shaped gondolas. The wings were equipped with flaps and ailerons. The rear tail unit consisted of a simple rudder on the vertical stabilizer and did not have horizontal stabilizers.

The retractable landing gear consisted of four wheels. Two smaller wheels were located inside the fairly large wing gondolas. In the lower part of the fuselage, an additional and larger pair of landing wheels was located.

The cockpit was placed to the front of the central fuselage. The canopy was made of plexiglass but besides that, little is mentioned of the cockpit design.

While the experimental glider was unpowered, if successful it was planned to add two unspecified jet engines inside the wing gondolas.

 

The side and top drawing of the Ikarus 453MW. The wing design while unusual was not used on any other Yugoslavian aircraft design. Source: www.vazduhoplovnetradicijesrbije.rs
The Ikarus 453MW had a landing gear consisting of three landing wheels units. Two smaller ones are located in the wing gondolas and one in the central fuselage. Source: www.vazduhoplovnetradicijesrbije.rs

Testing and Cancellation of the Project

The Ikarus 453MW prototype was completed and ready for testing by November 1952. On the 28th of November, the first test flight was made by Metodije Bojković. The test flight was undertaken at the Batajnica Airfield near the capital of Belgrade. Unfortunately for all present, an accident occurred. During take-off, the glider veered off the runway. While the pilot was unharmed the glider was damaged and the test flight had to be temporarily postponed.

After repairs were made, additional aerodynamic wind testing was undertaken to test the overall design shape. As these proved satisfying, another test flight was to take place. The Ikarus 453MW was towed up to 3 km of altitude by an Ikarus 213 and then released. While the flight itself was without problems, another accident occurred during landing. After analysis of available data, it was concluded that the pilot was not to blame as he was not properly instructed on how to fly the Ikarus 453MW which had an unusual wing design. Following the second accident, an order was given by the Yugoslav Army officials to cancel the Ikarus 453MW project.

A Nuclear Carrier

Author  N. Đokić (Projektat Jugoslovenskog Strategijskog Bombardera) gives us an interesting reason for the Ikarus 453MW design. It is a generally lesser-known fact, but during this time, the JNA was highly interested in developing nuclear weapons. The JNA’s involvement in Yugoslavian nuclear research development is to this day still not completely clear. This source mentioned that according to some secret JNA documents, the Ikarus 453MW was intended to be an aircraft that could quickly deliver a nuclear warhead to enemy targets. For this reason, the final aircraft was to be able to carry one 2-ton nuclear warhead at a speed of 850 km/h. The operational range was to be some 2,000 km, and the maximum service ceiling was 11,000 meters. In the meantime, a contingent of F-84G jet aircraft was acquired from the United States. As these were capable of carrying nuclear weapons there was no need to further proceed with the Ikarus 453MW project.

Whether there is any truth to the nuclear weapons plans is difficult to determine. The JNA and the Yugoslavian political hierarchy were publicly known to be quite interested in developing nuclear capability. Of course, this would demand a massive amount of resources, highly trained personnel, and well-developed industrial capacity, all of which Yugoslavia simply lacked in these early years of its existence. Its industrial capacity and infrastructure were almost completely destroyed during the war, and it would likely, if at all possible, take decades of commitment and investment to actually build a nuclear weapon. Hypothetically, even if Yugoslavia was able to develop nuclear weapons in the following decades, all research and experience gained on the Ikarus 453 would be outdated by that time. In conclusion, it could not be ruled out that the JNA had overzealous and ambitious plans to test the concept of using a swift aircraft to deliver this weapon. In reality, Yugoslavia simply lacked any means to actually produce such weapons. Despite this, testing this unusual wing design, albeit in a limited manner, at least provided Yugoslav aircraft engineers with additional experience.

Surviving Model

While unfortunately the Ikarus 453MW glider was not preserved, a small model replica is on display at the Nikola Tesla Serbian Aviation Museum near Belgrade.

The Ikarus 453MW wooden replica is located in the Belgrade Aviation Museum. Source: www.vazduhoplovnetradicijesrbije.rs

Conclusion

The Ikarus 453MW was quite an interesting design mostly due to its unusual wing shape. Its overall history, especially the trials is somewhat obscure. While the prototype was involved in two accidents, this was not the fault of the design but rather poor communication with the pilot, who was not informed of its flight characteristics.

Specification Ikarus 453MW
Wingspan 7.5 m /  24 ft 7 in
Length 5.85 m / 19 ft 2  in
Height 2.01 m /  6 ft 7 in
Maximum Takeoff Weight 1,720 kg / 3,792lbs
Crew One pilot
Armament
  • None

 

Experimental Ikarus 453MW

Credits

  • Written by Marko P.
  • Edited by Henry H. & Ed J.
  • Illustrated by Carpaticus

Sources:

8.8 cm Flak 18/36/37

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

8.8 cm FlaK 18/36/47 in the Anti-Tank role Source: T.L. Jentz and H.L. Doyle Panzer Tracts No. Dreaded Threat The 8.8 cm FlaK 18/36/47 in the Anti-Tank role

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.

This article covers the use of the 8.8 cm Flak gun in the original anti-aircraft role. To learn more about the use of this gun in its more famous anti-tank role visit the Tank Encyclopedia website.

 

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.

A captured Krupp gun was modified to be used for anti-aircraft defense by the Serbian Army during the First World War. Other warring nations also employed similar designs during the war. [telegraf.rs]
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.

The Krupp 8.8 cm anti-aircraft gun. [Wiki]
As the newer German anti-aircraft guns became too heavy to be used in more mobile configurations by mounting them on trucks, they had to be towed instead. Source: W. Muller The 8.8 cm FLAK In The First and Second World War

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’s first 8.8 cm Flak 18 prototype. [8.8 cm Flak 18/36/37 Vol.1]
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.

This particular gun is equipped with a loading rammer with a new round which is ready to be loaded into the chamber. [Pinterest]
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).

When stationary, the gun had a height of 2.1 meters, which offered a relatively large target for enemy gunners. Good camouflage and well-selected positions were vital for its crew’s survival. [defensemedianetwork.com]

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°.

The two control handwheels. The front handwheel is for traverse while the rear one is for elevation. Source: W. Muller (1998) The 8.8 cm FLAK In The First and Second World Wars, Schiffer Military

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 Flak at its maximum elevation. Source: T.L. Jentz and H.L. Doyle Panzer Tracts No. Dreaded Threat The 8.8 cm FlaK 18/36/47 in the Anti-Tank role

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 8.8 cm fuze setter. [Pinterest]

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.

The Stereoscopic Director 36 was a vital piece of equipment that provides the necessary acquisitions of targets. [waralbum.ru]
Common 8.8 cm anti-aircraft employment was a square formation with four guns. Source: W. Muller The 8.8 cm FLAK In The First and Second World War

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.

A close-up view of the dismantled 8.8 cm Flak cross-shaped platform. The two folding side outriggers are missing. The central octagonal base would later be replaced with a much simpler square-shaped one. Source: German 88-mm AntiAircraft Gun Materiel, US War Department Technical Manual
The side outriggers could be lowered during firing. In order to provide better stability during firing the gun, the crew could dig in the steel pegs located on each of the side outriggers. At the bottom of each outrigger were round-shaped leveling jacks. Their purpose was to prevent the gun from digging into the ground and to keep the gun level on uneven ground. Source: German 88-mm AntiAircraft Gun Materiel, US War Department Technical Manual
The side outriggers are fully raised during transport. [o5m6.de]
To prevent damaging the gun during transport, a large travel lock was installed on the front outrigger. Source: German 88-mm AntiAircraft Gun Materiel, US War Department Technical Manual

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.

The two trailer units were connected to the front and rear outriggers by using simple hooks, which would quite easily be disengaged. Source: German 88-mm AntiAircraft Gun Materiel, US War Department Technical Manual
The front view of the Sonderanhanger 201 dolly could be easily identified by the use of only two wheels. The chain’s winch would be used to raise the outriggers. Source: German 88-mm AntiAircraft Gun Materiel, US War Department Technical Manual

Firing with both trailer units still connected to the gun as possible, but it raised the height of the gun and prevented it from engaging air targets. [o5m6.de]
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.

Most guns were initially not provided with a shield. Given its original purpose, this is not surprising. Source: T.L. Jentz and H.L. Doyle Panzer Tracts. Dreaded Threat The 8.8 cm FlaK 18/36/47 in the Anti-Tank role
Most guns that were issued for field use would be provided with a large 10 mm thick front armored shield. The wire cover on the top was used for camouflage. Source: T.L. Jentz and H.L. Doyle Panzer Tracts Dreaded Threat The 8.8 cm FlaK 18/36/47 in the Anti-Tank role
On the left side of the gun shield, there was a hatch that would be used for the gunner to find his aerial targets. [worldwarphotos.info]

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.

The 8.8 cm Flak used large one-piece ammunition. It was stored in either wooden or metal containers. [defensemedianetwork.com]

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.

The 8.8 cm guns that were used for supporting ground units had a fairly large crew. [Pinterest]
The Sd.Kfz. 7 half-tracks were the primary towing vehicles for this gun. [defensemedianetwork.com]
Six-wheeled heavy-duty trucks would sometimes be used due to the lack of half-tracks. They did not offer the same driving performance. [worldwarphotos.info]

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.

The 8.8 cm Flak 37 introduced the use of specially designed directional dials, which help the crew better adjust the gun. Source: Norris 8.8 cm FlaK 16/36/37/ 41 and PaK 43 1936-45

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.

An 8.8 cm Flak gun in Spain.[weaponsandwarfare.com]

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.

Prior to the war, the 8.8 cm guns war could have been often seen on military parades, exercises, and ceremonies. Source: W. Muller The 8.8 cm FLAK In The First and Second World Wars

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.

Some of the 8.8 cm guns were destroyed or abandoned. Source: A. Radić Arsenal 51

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.

The majority of the 8.8 cm Flak guns built would be used in static defense without the cross-shaped platform. These would mostly be destroyed by their crews to prevent their capture when the Allies made their advances into Germany. Source: W. Muller The 8.8 cm FLAK In The First and Second World Wars

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.

A 8.8 cm by the Atlantic coast in 1941. This crew had already achieved two kills, judging by the kill marks on the barrel. Source: W. Muller The 8.8 cm FLAK In The First and Second World Wars

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.

The Flak provided necessary and crucial defense of vital industrial centers. Source: W. Muller The 8.8 cm FLAK In The First and Second World Wars

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 VOMAG truck was armed with 8.8 cm guns. Source: W. Muller The 8.8 cm FLAK In The First and Second World 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.

Some 12 Sd. Kfz. 9 were modified by receiving an 8.8 cm gun. [worldwarphotos.info]
The 8.8 cm Flak auf Sonderfahrgestell Pz.Sfl.IVc prototype.[uofa.ru]
The strange-looking Panzer IV armed with this gun. [armedconflicts.com]
Mounting the 8.8 cm gun on railroad cars was a common sight in Germany at early stages of the war. There was various design that may differ greatly from each other. [defensemedianetwork.com]

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.

The 8.8 cm Flak in the Yugoslavian People’s Army service, during military training near the capital in 1955. Source: A. Radić Arsenal 51
Two 8.8 cm Flak guns were reused by replacing the gun with two 262mm rocket launchers. While not a success, these two remained in use up to 1998. [srpskioklop.paluba.info]

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

The Flak 88 mm gun in towing postion

 

Flak 88 in firing position

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/

 

Fiat G.50 in Independent State of Croatia Service

Independent State of Croatia flag Independent State of Croatia (1942)
Fighter –  16 Operated

In NDH service the Fiat G.50 did not receive any modifications, with the original Italian camouflage remaining. The only change was the addition of Croatian military markings and new identification numbers. [Wiki]
Following the creation of the Nezavisna Država Hrvatska (Independent State of Croatia), its Air Force was plagued with many problems from the start, including a lack of modern aircraft. While generally heavily reliant on the Germans to provide them with better equipment, they were unwilling to secure any deliveries of aircraft. To resolve this issue the NDH’s Air Force officials managed to persuade Italy to sell them 10 Fiat G.50bis fighters, which remained in use up to 1945.

A Brief History of the NDH

Following the end of the First World War, Kraljevina Srba Hrvata i Slovenaca (The Kingdom of Serbs, Croats, and Slovenes – SHS) was formed in December of 1918 with the aim of uniting all Southern Slavs. This new state was, at least in theory, based on the principles of equality for these three nationalities. In reality, this Kingdom was a politically and ethically divided country. During the 1920s, there were huge political disagreements between the major parties which brought about questions regarding the continued existence of the Kingdom of SHS. This division was especially noted between the Serbian and Croatian politicians, which ultimately culminated in the assassination of several Croatian Peasant Party members, including the leader, Stjepan Radić, by a Serbian Politician in 1928.

On 6th of January, 1929, King Aleksandar Karađorđević, in an attempt to avoid the incoming political crisis, led the country into a dictatorship by abolishing parliament. He also introduced a number of political changes, including changing the name of the country to Kraljevina Jugoslavija (Kingdom of Yugoslavia.) This essentially did not resolve any of the existing problems, as inter-ethnic tensions persisted. During the early 1930s, the first mentions of Croatian Ustaše (the precise meaning is unknown, but could be roughly translated as insurgent) ultranationalist revolutionary organizations began to appear in Yugoslavia. Their main aim was the liberation of the Croatian people from Yugoslavia, by all means necessary, even by force. One of the most prominent figures of this organization was Ante Pavelić.

Ante Pavelić was a high-ranking Ustaša member from the start, and later de facto leader of the NDH. [Wiki]
The Ustaše organization participated in the assassination of the Yugoslav King, Alexander Karađorđević, in Marseille in 1934. This assassination backfired to some extent for the Ustaše organization. Not only did it not lead to the collapse of Yugoslavia, but relations with Italy also improved under the Regent Prince Pavle Karađorđević in the following years. This led the Italian authorities to effectively end their support for the Ustaše and even arrested some of its members, including Pavelić.

After years of inactivity, the Ustaše benefited when the Yugoslavian government, which supported the Axis, was overthrown by pro-Allied officers in a military coup at the end of March 1941. Adolf Hitler almost immediately issued an order that Yugoslavia should be occupied. The Italians, preparing to join the war against Yugoslavia, began to support the Croatian Ustaše movement once again. With the collapse of the later Kingdom of Yugoslavia during the Axis invasion after the short April War of 1941, Croatia, with German aid, was finally able to declare independence, albeit becoming a fascist puppet state. Ante Pavelić was chosen as the leader of this puppet state. Officially, the NDH was announced on 10th April 1941. The new state received a significant territorial expansion by annexing most of western Yugoslavia, including Bosnia, parts of Serbia, and Montenegro. The Adriatic coast, while nominally part of the NDH, was actually controlled by the Italians until 1943.

The NDH took over a large portion of the Yugoslavian territories. [Wiki]

Formation of the NDH Air Force

Following the collapse of the Kingdom of Yugoslavia, NDH began organizing its newly-created armed forces. Its Air Force was created on the 19th of April, 1941. The leadership of the new Air Force was given to Colonel Vladimir Kren. Immediately, work began on creating adequate structural organization, acquiring manpower, and procuring equipment. Initially, plans for arming this Air Force were ambitious, including some 140 modern aircraft, such as the Ju 88 and Me 109. Its officials were quite disappointed as Germans were not willing to provide these. Instead, the NDH officials had to make do with the leftovers of the Former Royal Yugoslav Air Force, which was in German hands. NDH officials made a request that included over 50 aircraft. The Germans once again disappointed them and gave NDH only those aircraft that were mostly obsolete, while transferring the better aircraft, like the Hurricanes, to Romania instead. The only other way to acquire more capable aircraft was to ask the Italians. This is what the NDH Air Force officials did in early 1942.

The NDH Air Force was initially equipped with surviving Yugoslavian aircraft, in this case, Rogožarski P.V.T. [The Croatian Air Force In The Second World War]

The Fiat G.50 brief history

During the thirties, the Italian Ministry of Aviation (Ministero dell Aeronautica) was interested in adopting a new, all-metal monoplane fighter and ground-attack aircraft for the Italian Air Force. In April of 1935, engineer Giuseppe Gabrielli began working on a new low-wing, all-metal plane named G.50. On 28th September 1935, Gabrielli submitted his project to the Ministry of Aviation. Military officials were impressed by the design and asked him to proceed with its work. As Fiat’s production capacities were overburdened, work on this new project was instead moved to the CMASA works at Marina di Pisa, part of Fiat since 1931. Giuseppe Gabrielli was finishing his last drawings and the list of needed materials and equipment in June 1936.

The prototype was finally ready at the beginning of 1937 and was transported to the city of Turin for further testing. This prototype, under registration number MM 334, made its first test flight on 26th February 1937. Once accepted for service, the Fiat G.50 would become the first Italian all-metal fighter. Between 1938 to 1943 some 774 to 791 of all versions of the G. 50 would be built. These saw combat service starting from the Spanish Civil War, until 1943 when the few surviving aircraft were reassigned to secondary roles.

A G.50 flying together with a German Bf-110, possibly during the Battle of Britain. [Wiki]

In Yugoslavia

The Fiat G. 50 participated during the short Invasion of Yugoslavia in April 1941. Two fighter groups, the 24th, and 154th, which had 53 G.50 fighters in total were allocated for this operation. They mostly performed a few escort missions. Due to the rapid collapse of Yugoslavia’s Royal Army, these saw limited actual combat use, if any. Afterward, the Fiat G.50 was allocated to other fronts. During 1942 and 1943, limited numbers of these aircraft were used for ground attack operations against the Yugoslavian Partisans.

In NDH’s Hands

By 1942, most of the available aircraft in NDH Air Force were in poor condition, mostly due to a general lack of spare parts. NDH Army officials approached Italy with a request for 9 improved Fiat G.50 and one two-seater version. The Fiat G.50bis were slightly modified versions that had an increased fuel load, a redesigned rear fuselage and vertical stabilizer, better glazing of the cockpit, and other minor changes. But in essence, it did not offer many improvements compared to the basic version. The G.50 B bipost (two-seater) was a modified G.50 fighter version with a new cockpit and dual controls for a pilot and trainer. The front section of the cockpit was fully enclosed, in contrast with the rear which was open. The main armament was removed on the G.50 B. This version was very successful, as it was easy to build and offered almost the same flying performance as the single-seat version.

The Fiat G.50 B version with a longer cockpit design for the instructor and the student. [alieuomini.it]
A group of six NDH pilots was sent to the Fiat company in Torino for training in January 1942. The entire acquisition process of new aircraft took several months to complete. The 9 Fiat G.50bis (serial number MM.6178 to 6186) were finally allocated to the NDH. These arrived in Croatia in April 1942. The Fiat G.50B two-seater took even more time to be delivered, arriving in late June 1942. These would be stationed on the Borongaj airfield near Zagreb. Initially, these were used for pilot training. Due to the poor condition of the airfield, two were lightly damaged during landing.

The Fiat G.50bis in NDH service. [asisbiz.com]
For the necessary pilot training, one modified Fiat G.50B two-seater was also acquired. [The Croatian Air Force In The Second World War]

Combat Use

Almost from the start, the new NDH regime began the persecution of all non-Croatian citizens. The Serbian, Roma, and Jewish populations were especially targeted, with numerous atrocities and arrests. Croatians who did not agree with this regime were also persecuted. In response to the NDH’s actions against Yugoslavian civilians, resistance movements began to emerge on its territory. Their Air Force was used in various roles during this time, but due to generally obsolescence of equipment, their impact would be quite limited.

The acquisition of more aircraft like the Fiat G.50 offered a slight increase in its offensive capabilities. Once in service, these received new registration numbers ranging from 2501 to 2509. The single Fiat G.50B received the 3510 designations. In July, five would be allocated to the Rajlovac airfield near Sarajevo. In September three were moved to the Banja Luka to be part of the 16th squadron.

After April 1943 most were pulled back to Zagreb where they were attached to the 1st Squadron. When Italy capitulated to the Allies, all warring parties in Yugoslavia rushed in to take over the abandoned Italian weapons, armored vehicles, and a few remaining aircraft. At Zadar airfield, there were six Fiat G.50 aircraft. These would be captured by the NDH forces. Three of them received 5686, 5956, and 5186 designations. The newly acquired fighters were primarily positioned at Kurilovac and Velika Gorica airfields.

By 1944 it was becoming obvious that the Axis would lose the war, as a result many soldiers and pilots from the NDH Army and Air Force tried to escape to the Partisans. On the 2nd of September 1944, air force pilot Andrija Arapović with a Fiat G.50 (reg. Num. 3505) escaped to the island of Vis, under the control of the Yugoslav communist Partisans. Partisan forces put the captured G.50 to use during the war and it would remain in service up to 1946. An interesting fact about Andrija Arapović’s G.50 aircraft is that it still exists today and can be seen in the Belgrade Military Aviation museum near the Nikola Tesla Airport in Serbia. This is the only surviving example of a G.50 in the world. Another Fiat G.50 escaped joining the Allies in Italy.

The Fiat G.50bis was piloted by pilot Andrija Arapović. On the 2nd of September 1944, he fled to the Partisan side. [The Croatian Air Force In The Second World War]
By this point the Allies had achieved almost complete air supremacy over southern Eastern Europe, thus flying the slower Fiat G.50 became quite dangerous. In April 1944 several NDH aircraft, including two Fiat G.50, were destroyed in an Allied bombing run on Borongaj. Due to their obsolescence, even the NDH’s best fighters could do little against Allied bombers. In addition, the chronic lack of fuel led to a reduction in combat flights. By mid-September 1944, only 7 aircraft were listed as operational. In October most were allocated to the 2nd Squadron, which was also equipped with MS 406 fighters. When the Partisans liberated Zagreb, some 9 aircraft in various conditions would be captured. Some would be put to use after the war, but their use would be limited.  These would be removed from service by the 1st of April 1946.

The Fiat G.50bis were often used to protect Zagreb but could do little against more modern Allied bombers. [The Croatian Air Force In The Second World War]

Technical Characteristics 

In NDH service no known modifications were made on the Fiat G. 50. The G.50 was a single-seat, low-wing, all-metal fighter plane. The main fuselage was made from four angular-shaped longerons. The wing construction consisted of a center section which was made of a steel tube connected to the lower fuselage and two metal spars connected with ribs. The fuselage, wing, and tail were covered with duralumin sheets. The only fabric-covered parts were the movable control surfaces in the wings and the tail. It was powered by the 840 hp (626 kW) Fiat A 74 RC 38, a 14-cylinder radial piston engine. An all-metal three-blade propeller produced by Fiat was used.

The G.50 was equipped, like most modern aircraft of the time, with inward retracting landing gear, but the rear tail wheel was fixed. In later improved versions, the rear tail wheel was changed to a retractable type.

The main armament consisted of two forward-firing 12.7mm Breda-SAFAT heavy machine guns, with some 150 rounds of ammunition for each machine gun. The guns were placed behind the upper engine cowl and were synchronized in order not to damage the propeller.

Conclusion

The Fiat G.50 was one of few modern fighters available for NDH service. Their use would be greatly hampered by ever-increasing Allied Air supremacy, lack of fuel, and fear of their pilots defecting. Despite being acquired in relatively small numbers many of them would survive the war albeit in poor condition, while some would see a few more years of service by the newly created Yugoslav Air Force.

Fiat G.50 Specifications
Wingspan 10.9 m / 35 ft 11 in
Length 8 m / 26 ft  3 in
Height 3.28 m / 10 ft 7 in
Wing Area 18.25 m² / 196.5 ft²
Engine One 840 hp (626 kW) Fiat A.74 RC.38, 14 cylinder radial piston
Empty Weight 1,975 kg / 4,350 lbs
Maximum Takeoff Weight 2,415 kg / 5,324 lbs
Fuel Capacity 316 l
Maximum Speed 470 km/h / 292 mph
Range 445 km / 267 mi
Maximum Service Ceiling 10,700 m / 35,100 ft
Climb speed Climb to 6,000 m (19,700 ft) in 7 minutes and 30 seconds
Crew One pilot
Armament
  • Two 12.7 mm Breda-SAFAT heavy machine guns

Credits

  • Written by Marko P.
  • Edited by Henry H. & Ed J.
  • Illustrated by Haryo Panji

Sources:

  • D. Nešić (2008), Naoružanje Drugog Svetsko Rata-Italija, Beograd.
  • G. Cattaneo, The Fiat G.50, Profile Publications number 188
  • P. Verganano (1997), Fiat G.50,, La Bancarella Aeronautica – Torino.
  • D. Monday (1984, 2006), The Hamlyn Concise Guide To Axis Aircraft Of World War II, Aerospace Publishing Ltd.
  • V. V. Mikić, (2000) Zrakoplovstvo Nezavisne Države Hrvatske 1941-1945, Vojno  istorijski institut Vojske Jugoslavije.
  • T. Likso and Danko Č. (1998) The Croatian Air Force In The Second World War, Nacionalna Sveučilišna Zagreb.
  • I. Černiševski (2012) Maketar Plus, IPMS Srbija

 

Modli J.M. 8

Yugoslavia flag Yugoslavia (1939-1950)
Trainer – 2 Prototypes

The Modli-8 in use with the Yugoslav Aviation after the war. www.paluba.info

The Modli J.M. 8 was designed in the Kingdom of Yugoslavia, built by the Independent State of Croatia (NDH), and after World War II, operated by the Federal People’s Republic of Yugoslavia (FPRY). It was an inexpensive training aircraft that would be used in this role up to 1950.

The Beginning

The story of the Modli J.M. 8 began in 1938, when an aircraft engineer from the 1st Air Force Regiment (stationed at Novi Sad), Josip Modli, finished work on a new light training aircraft design. He originally intended to design and build a single seat trainer that was cheap and simple to manufacture by using mostly wood. He also intended to gain the interest of amateur aviators and aeroclubs with a low price. The J.M. 8 designation comes from the initials of the designer’s name. Due to its small size and low price, it earned the nickname Komarac/komaрац (Mosquito).

The following year, Modli actually began building this aircraft. He reused the small 18 hp engine taken from a damaged French HM.14 Pou du Ciel (Nebeska Vaš/Небеска Ваш in Serbian). Four had been bought from France in 1935 but, due to construction problems, their use was limited and all were damaged during test flights. One was tested at Novi Sad, where the 1st Air Force Regiment was stationed.

Modli reused the engine from a damaged HM.14 Pou du Ciel for his first prototype. Four of these small aircraft were bought from France. www.vazduhoplovnetradicijesrbije.rs

At that time, word of his design and work reached the Yugoslavian Air Force Headquarters. Headquarters then instructed (or ordered, depending on the sources) aircraft engineer Tišma, who was co-owner of the Albatros aircraft manufacturer from the cit of Sremska Mitrovica, to contact Modli. After short negotiations, Tišma and Modli reached an agreement that Albatros should finish the construction of the J.M. 8.  If the design received any mass production orders, Modli agreed to provide Albatros with a license for its production.

The J.M. 8 was completed in early 1941, with testing scheduled to begin in March. Due to bad weather, Albatros’ main airport at Ruma was flooded during March and early April, so no tests flights were conducted. During the outbreak of the April War (Axis invasion of Yugoslavia), all finished and partially constructed planes from Albatros were loaded on a train on the 10th of April. Because of the great confusion due to the outbreak of war and the lack of documentation, the fate of this train and its cargo is unknown to this day.

After the end of  the April War, the Serbian Air Force Commission made estimates of all unpaid pre-war designs, including the Modli J.M. 8, in order to arrange for future payments for military contracts. The commission, after analysis of the Modli J.M. 8 documentation, concluded that the aircraft did not meet any military requirements and was suitable for civilian use only.

Technical Characteristics 

The Modli J.M. 8 was designed as a single engined, high wing, mixed construction (but mostly wood) training aircraft. Its fuselage had a simple design made of plywood. The high wings and the rear tail were made of a wooden structure covered with fabric. For better flight controls, Modli used two modified Gottingen 426 longerons. The wings were connected to the fuselage with three “N” shaped metal bars on both sides and with two additional ones in the centre. The tail had a large rudder and elevators made of wood.

It was powered by the two cylinder Aubier & Dunne 18 hp engine. The engine compartment was covered with duralumin. The two-bladed propeller was made of walnut. A fuel tank with a capacity of 16 liters was placed in the center of the wing.

The Aubier & Dunne 18 hp engine was reused for the first prototype. Source: www.vazduhoplovnetradicijesrbije.rs

The landing gear was fixed, but was equipped with rubber shock absorbers for greater comfort and control during  landing. There was no rear wheel, being instead equipped with a small skid and shock absorber.

The pilot’s cockpit was fully open with a small windshield at the front. The cockpit had a simple design and was equipped with basic controls and instrumentation. These flight instruments included an airspeed indicator, fuel level, tachometer, and altimeter. As the first prototype was never adequately tested, details about its flying performance are not known.

During World War II

After the Yugoslavian capitulation, its territories were divided between the Axis forces. The Germans created the Independent State of Croatia (Nezavisna Država Hrvatska) puppet state. Despite promises of sending military equipment, weapons and aircraft, the NDH was mostly supplied with older or captured equipment. The NDH aviation industry was heavily dependent on supplies from Germany and Italy, as it lacked any major production capacity or industrial development, meaning domestic production was not possible. The only attempt at domestic production was with the Modli aircraft.

In 1941, Modli joined the new NDH Air Force with the rank of Flight Captain as a flight school instructor. He immediately began working on his second prototype, now simply called Modli-8. Unlike his first prototype, the second one was powered by a stronger four-cylinder Praga-B giving 40 hp. As this engine was too strong for the prototype, its power was reduced to just 20 hp. For the landing gear, two smaller rear wheels from a German Me-109 were reused. The Modli-8 was also shorter in comparison to the first prototype by 0.94 ft (15 cm).

In 1943 Modli was transferred to the technical workshop of the 1st Air Base in Zagreb, where he continued to develop his plane. In 1944, the Modli-8 was completed and introduced to NDH operational service according to authors T. Lisko  and D. Čanak. Unfortunately, they do not give more information on its service history. According to authors B. Nadoveza and N. Đokić on the other hand, noted that Modli deliberately delayed the production of the Modli-8 and it was never fully completed for use by the NDH.

On 26th October 1944, Josip Modli fled to Slovenia at the helm of a Bücker Bü 131 “Jungmann” in hopes of joining the Yugoslav Communist Partisans. Meanwhile, his assistants and friends in Zagreb hid the Modli-8 prototype in the attic of an old shed. Due to the chaos and confusion caused by the war, it was easy to hide the small and lightweight prototype. The Modli-8 would survive the war intact.

The Modli-8 was the only NDH domestically-built aircraft during the War. These two pictures may be the only ones of the Modli-8. Source: www.paluba.infok

In NDH service, the Modli-8’s lower fuselage, wings, and tail were painted in silver. The upper part of the fuselage and vertical stabilizer was blue. The wings struts were painted in red, while the middle of the fuselage wore a red stripe on both sides with a white outline. There were NDH markings with a large “JM8” painted on the tail. The color scheme would remain the same after the war but the NDH marking would be replaced with the Communist Star.

After the War

After the collapse of the NDH and the German forces in Yugoslavia, Modli, now Captain in the Yugoslav People’s Army, moved his prototype from Zagreb to Skopje, where it was completed in an army workshop. Modli himself flew the prototype during the summer of 1945. Surprisingly , he did not report this flight to his superiors and an alarm was raised, with several fighters launched to intercept him. Modli was lucky, as this incident did not affect his military career. The Modli-8 was, by order of Air Force Command, moved to Belgrade for further tests. The aircraft proved to be a good design, as it was easy and pleasant to fly according to test pilot Vasilije Vračević. There were some issues with the sensitivity of the large rudders and elevators during flight. For take off, it only needed a very short 170 m (558 ft) runway, and could land on a 125 m (410 ft) airfield. The maximum speed was around 100 km/h 223 mph at an altitude of 1 km.

The Modli-8 was then given to Aircraft Center Vršac, where it was used for training and propaganda flights. It was used operationally up to 1950, when it was removed from Army service. During its operational service, the Modli-8 was also used as a glider trainer. Under the right conditions it could be used as a glider with the engine shut off, which was useful for glider training.

Josip Modli later (date unknown) designed a two-seater version named Modli-9, but it was never fully completed. Both the Modli-8 and the unfinished 9 were given to the Croatian Technical Museum (Zagreb)  after the death of Josip Modli in 1974.

Production and Modifications

Despite being cheap, easy to build, and pleasant to fly, the Modli-8 was never adopted for military or civilian service. The first prototype was never fully tested due to the outbreak of the war and was lost (precise fate unknown). The second prototype was built during the war and was in use up to 1950. Despite the good feedback for its flight performance from the military, the Modli-8 was rejected for production, mostly due to the recent adoption of the BC-3 Trojka.

Modli J.M.8 – First prototype powered with Aubier & Dunne engine, lost in WW2.

Modli-8 – Second prototype powered by Praga-B engine and with other minor improvements, in service until 1950.

Modli-9 – Two-seater version, never fully completed.

Conclusion

Despite the few number of built aircraft, the Modli J.M. 8 had a small but interesting development history, changing owners several times. It had the honor of being the only aircraft built in Croatia during World War II. Despite its simplistic nature, it saw extensive use as a trainer after the war.

Operators

  • Kingdom of Yugoslavia – One built prototype
  • Independent State of Croatia (NDH) – Constructed one prototype but never tested
  • Federal People’s Republic of Yugoslavia (FPRY) – Operated the Modli-8 up to 1950.

Modli-8 (second prototype) Specifications

Wingspans 31 ft 2 in / 9.5 m
Length 19  ft 7 in / 6 m
Height 6 ft  / 1.85 m
Wing Area 36.25 ft² / 11.05 m²
Engine One four cylinder Praga-B 40 hp engine
Empty Weight 474 lbs / 215 kg
Maximum Takeoff Weight 705  lbs / 320 kg
Fuel Capacity 16 l
Climb Rate to 1 km In 10 minutes
Maximum Speed at 1 km 223 mph / 100 km/h
Take of run 558 ft / 170 m
Landing run 410 ft / 125 m
Range 124 mi / 200 km
Maximum Service Ceiling 5578 ft / 1,700 m
Crew 1 pilot
Armament
  • None

Gallery

Illustrations by Carpaticus

Modli Croatia
Modli Yugoslavia

Sources:

  • T. Lisko  and D. Čanak (1998), The Croatian Air Force In The WWII, Nacionalna i sveučilišna knjižnica, Zagreb
  • Vojislav V. Mikić, (2000) Zrakoplovstvo Nezavisne države Hrvatske 1941-1945, Vojno  istorijski institut Vojske Jugoslavije
  • B. Nadoveza and N. Đokić (2014), Odbrambena Privreda Kraljevine Jugoslavije, Metafizika Beograd.
  • Nebojša Đ.and Nenad M. (2002), IPMS Yugoslavia and Yugoslavian Aviation Special Interest Group Bulletin No 1-4, 

 

 

Fizir Prelazni FP-2

Yugoslavia flag Yugoslavia (1933-1947)
Training aircraft – 81 Built

Front view of the FP-2. [vazduhoplovnetradicijesrbije.rs]
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.

The FP-2 was considered a successful basic trainer by the Royal Air Force before the war. [airwar.ru]
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.

FP-2 in Croatian service during the Second World War. [histaviation.com]
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.

This FP-2 (6822) is the plane in which Croatian pilot Mitar Оbućanin defected to the Partisan side. It was then put into service by the Partisans from the isle of Vis. The FP-2 received a large Red Star painted on its side.[vazduhoplovnetradicijesrbije.rs]
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.

Side view of the FP-2. [airwar.ru]
One of the 13 FP-2s operated by the new Communist Yugoslav Air Force after the war. [vazduhoplovnetradicijesrbije.rs]
 

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

FP-2 in Croatian service during the Second World War
FP-2 in Italian Service – 39ª Squadriglia

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

Ikarus 214

Yugoslavia flag Federal People’s Republic of Yugoslavia (1948-1967)
Multi-Role Twin Engined Aircraft – 23 Built

The Ikarus 214 [otpisani.niceboard.com]
After World War Two, the new Communist Yugoslavian Air Force Command began a long process of restoring the destroyed aviation industry. The first attempts were made in the late 1940s, when several new and experimental designs were built, including the Ikarus 214. While most of these would remain prototypes or be built in small numbers, they would serve as a base for future developments and the experience gained would be used in the following years.

History

The first steps towards rebuilding the new Communist Yugoslav aviation industry were made during the war on 24th October 1944. Negotiations with representatives of many pre-war aircraft manufacturers about the possibility of reviving the devastated aircraft industry were held at Zemun near the capital city of Belgrade. Many pre-war aircraft industry designers and engineers would survive the war, and would be used to form the base of the future Yugoslav aviation industry.

Ikarus 214 D Prototype in Flight [paluba.info]
Two years later (23rd February 1946), the Aeronautical Technical Institute created a competition for the development of four new designs. One was for a flying school and tourism aircraft, while the others were for a two-seater basic trainer, an advanced trainer, and a multi-seat trainer version that could potentially be used as a transport plane. The Aeronautical Technical Institute was a pre-war institution which was responsible for placing orders and monitoring new aircraft development. During the period of 1947 to 1952, several different designs, including the maritime role, what would become the Ikarus 214, were produced. 

Constructor Group No.5, under the leadership of the aircraft engineer and professor Sima Milutinović, received orders to design a light two-engined transport and bomber crew trainer aircraft under the military designation 214. After the calculations and drawings were completed, the production of the first prototypes began in 1948 at the Ikarus factory. By 1949, two prototypes were completed and were designated 214P and 214D.

Name

The original military designation of this plane was simply 214. After the first two prototypes were built, the manufacturer’s name, Ikarus, was added to the designation. However, some sources call it the type 214 or simply the 214. This article will use the 214 designation for the sake of simplicity.

Technical Characteristics

The 214 was designed as a low wing, twin engine, mixed construction plane. Despite being primarily intended as a transport and trainer plane, the 214’s fuselage was designed to be able to withstand bomber duties. The fuselage had an unusual design and was built by combining two monocoque “sandwiches” (two light skins placed around a thick core) shell construction (same as on the British de Havilland Mosquito which was in use with the Yugoslavian Air Force.) The 214’s fuselage was large and had plenty of room for use as a transport or passenger aircraft.  The 214 passenger version had 7 seats placed behind the pilot’s cockpit. On both sides of the fuselage, there were two rounded and two elongated windows. The 214 (except the later built 214PP and AM-2) had a large and fully glazed round shaped nose with good all round forward visibility.

The Improved 214AM-2 Anti-Submarine Variant
The 214 prototypes were powered by the weaker Ranger SVG-770C engines.

The wings were made of wood and consisted of two box shaped longerons. The whole wing was covered with birch glue. The twin tail vertical and horizontal stabilizers were also made of wood. The rudder and the elevator were made of duralumin and covered with canvas.

The first engine used by the two prototypes was the air-cooled Ranger SVG-770C providing 520 hp, with the two-bladed Hamilton standard type propellers. The second prototype, and all subsequent aircraft were equipped with the stronger nine-cylinder air-cooled Pratt & Whitney R-1340-AN-1, which delivered 600 hp. Four fuel tanks were placed in the wing longerons, with a total fuel load of 780 liters (206 gallons.) The 214 used B-95 gasoline as its main fuel.

The Ranger SVG-770C Engine [vazduhoplovnetradicijesrbije.rs]
The landing gear retracted (except on the first prototype) into the rear engine nacelles but was not completely covered. The rear tail wheel was fixed but was provided with a brake system. The landing gear was hydraulically driven.

The pilot’s cockpit was positioned above the front fuselage and provided a good all-around view. In the cockpit there were positions for two crew members (pilot and assistant) and dual controls which were connected with the rudders and elevators with wire. However, this flight control system was flawed, because it took a few seconds before the plane responded to the command given by the pilot, for example during turns, climbs, or descending maneuvers. This made the 214 particularly difficult to fly during harsh and bad weather. 

The front glazed nose provided a good all around forward view.

Inside the cabin were several flight instruments, such as the airspeed and altitude indicators (type Teleoptik 456-6 and 452, the 214AS version had two altitude indicators), two variometers (type Teleoptik 26B), a turn and slip indicator (type 441-0), a horizontal situation indicator (type Teleoptik 32C, the 214AS version was equipped with two), a magnetic compass (type 443-0), two engine tachometers, fuel and oil gauges, landing gear indicator, and thermometer. Additional equipment for the crew’s safety included parachutes, fire extinguishers, oxygen bottles, and heating & ventilation. In the first series of aircraft produced in 1958, a SCR-522 radio unit was installed This radio had 8 watts of power with a range of 50-290 km (30-180 mi) depending on altitude. The 214F version was equipped with a Rudi Čajevac radio-telephone.

One of the prototypes was armed with three 7.92 mm MG-15 machine-guns, one forward fixed, one on the side (not specified whether  it could be aimed) and one in the rear facing turret. The decision to use older captured German MG-15s was most likely based on the fact that the 214 was to be used as a trainer aircraft, with better and more modern armament reserved for front  line aircraft. The 214 could also be equipped with a bomb load of four 50 kg (110 lb) bombs. Weapons were rarely installed on the production versions, as they were used mostly for transport.

First Test Flights

The 214 made its first flight on 7th August 1949, at the Zemun airfield near Belgrade. Immediately, there were problems with the lack of an adequate retractable landing gear. As a temporary solution and to speed up the testing process, the engineers simply reused the landing gear from an Il-2 (which was in use by the Yugoslav Air Force), but for technical reasons it was not retractable and remained fixed. There were also problems with inadequate propellers, as the 214 prototypes had to use propellers designed for a single engine aircraft. Despite the fact that it was never intended to be used with a fixed landing gear, military officials demanded that the flight tests begin as soon as possible. During its first test flight, one of the two engines simply stopped working. The pilot made a turn back towards the airfield, but the 214 could not maintain altitude and the plane crashed killing the test pilot Lieutenant Sima Nikolić.

An investigation that was subsequently conducted found that the fixed landing gear and the poor choice of propellers created too much drag. The single working engine could not overcome this drag. In addition, the vertical tail surfaces proved to be inadequate.

Prior to this accident, the engineers and designers predicted, at least in theory, that the 214 could maintain a constant altitude with only one working engine. In case of such a scenario, the test pilots were instructed to fly to the large and open Borča field,  Belgrade, and land there. Why the pilot decided to return to Zemun airfield instead of proceeding to the instructed field was impossible to determine. Despite this accident, the development of the 214 would go on.

The second prototype was fully completed by December 1949. In order to avoid accidents, the second prototype spent almost two years being redesigned and tested. Unfortunately, there is no information about any flights made during this period, but it is possible that some were conducted. This plane received larger vertical tail surfaces and a new landing gear. More intense flight tests were made from 1951 on. During this time, different trainer configurations were tested. These were basic training variants with three crew members and no armament, a bomber training variant with four crew members with up to three machine guns and bombs, and as a passenger transport variant with two crew members, six passengers, and no armament.

The Pratt & Whitney R-1340-AN-1 became a standard production engine on the 214. [vazduhoplovnetradicijesrbije.rs]
During 1954 and 1955, the second 214 prototype was equipped with Pratt & Whitney R-1340-AN-1 engines. It made its first flight with these engines on the 16th of September 1955 without any problems. In 1957, the second prototype was modified for use as a photo-reconnaissance aircraft (serving as the basis for the later 214F variant). This prototype would be used in this role until September of 1959, when the plane was lost in an accident. 

In 1955, it was decided to put the 214 into limited serial production. It  began in 1957 (or 1958 depending on the sources) and, by the time it ended in 1960, a total of 21 (or 20 depending on the source) 214 planes were produced. 

Anti-Submarine role

In 1958, a decision was made by the Yugoslavian Air Force for the adaptation of the 214 for anti-submarine operation. The first series of 214s produced was allocated to the 97th Air Regiment (this unit was renamed into the 97th Anti-Submarine Regiment in November 1958). The first group of pilot officers from the 97th Air Regiment was moved to Zemun airfield for training on the 214 in October 1958. All pilots from the 97th Air Regiment (which was equipped with British de Havilland Mosquitos) completed training by July 1959. In the period of 1959 to 1960, there were 41 pilots in training, but the number was reduced to 25 in 1961 and 1962. The entire training process was carried out under the leadership of World War II veteran Captain Okanović i Semolić.

As the 214 lacked any equipment for anti-submarine operations, it could be used only in reconnaissance missions, and only weather permitting where visibility was good. In 1960, there were plans to improve the 214’s anti-submarine performance by adding the necessary equipment. One modified aircraft, under the new 214PP (No. 61004) designation, was tested by Captain Petar Savić on the 6th of May 1960. Two years later, a new anti-submarine version, 214AM2 (No.61015), also known as 214M-2, was tested in June 1962 by pilot Aleksandar Prekrasov. Both versions had a fully enclosed nose instead of the standard glazed one (the sources are not clear, but it appears that other 214  were also equipped with an enclosed nose). In addition, the 214AM2 was provided with a radar placed below the front nose. However, this improved version was still not up to the task of anti-submarine duties. Even if the crew spotted an enemy submarine, it could hardly do anything. Due to equipment delays, more extensive testing was not possible before 1963. The 214AM2 was tested in Batajnica (near Belgrade) and later in Pula on the Croatian coast. The tests of the 214AM2 were completed by 1965, and the results of these tests assessed the variant as partially successful. 

Even before these tests were completed, in May 1964, by the order of the Secretary of National Defense, the 97th Anti-Submarine Regiment was reorganized as 97th Auxiliary and Support Regiment and supplied with C-47 transport planes. The 214 was still in use with this unit but mostly in a transport role. This decision to remove the 214 from the anti-submarine role was based on the fact that they were not sufficiently equipped, and could not effectively engage submarines. The 214 would be used by this unit up to 1966, when they were removed from service.

The 214F 

Front view of the 214F version.

In 1960, three aircraft, designated as 214F, were built in the Ikarus factory to be used as photo-reconnaissance planes. The main difference was the removal of the seats inside the plane’s fuselage and replacing them with positions for a cameraman, his assistant, and  camera equipment. 

Limited Operational Service Life

Despite being designed to fulfill several different roles, the 214 (beside the two anti-submarine modifications) was mostly used as a light transport and sometimes for day and night bomber crew training. The aircraft that were used in this role received the 214AC or 214P designations and, in total, 18 were built of this version. The basic transport and training variant had 7 seats placed behind the cockpit, with four on the right, and three on the left side. In some sources, the passenger number is listed as 8. The idea to use the 214 as a light bomber was rejected due to the rapid development of more advanced fighter-bombers. The 214 had many technical problems during its operational use, such as inadequate radio equipment, problems with the control of the wing flaps, inadequate electric equipment for night flights, and cracks that would appear in the propeller spinners after extensive use. 

A parachute group in front of a 214 prior to take-off. [vazduhoplovnetradicijesrbije.rs]
Rear view of a 214. The Yugoslav flag (blue, white and red with a red star in the middle) was often painted on the tail. [otpisani.niceboard.com]

The 214 was mostly used by the Yugoslavian Air Force as a transport plane.

In Civilian Service

By 1966, only six 214 transport versions were still operated by the Yugoslavian Air Force. The next year, these six were withdrawn from service and given to the Aeronautical Association of Yugoslavia for use. They were registered as passenger planes with two crew members and seven passengers. These received the following civilian markings based on their stations: YU-ABN in Ljubljana, YU-ABO in Vršac, YU-ABT in Novi Sad, YU-ABS in Zagreb, YU-ABR in Sarajevo and YU-ABP in Skopje.

In 1968, only four were listed as operational and, by 1970, they were removed from the civilian registers. While they remain stored, some parachute flights were carried out after 1970. In the following years, all except one were scrapped. This aircraft (No.60019) was given to the Yugoslav Aviation Museum near the Capital of Belgrade in 2001. The plane is in a poor state of repair and is waiting for restoration. Due to the financial difficulties of the museum, there is only a small chance that it will be restored in the near future.

This is a civilian 214 stationed in Sarajevo. [paluba.info]
The only surviving 214 (No.60019) aircraft can be seen in the Belgrade Aviation Museum. [Wikipedia]

Production Run

As previously mentioned, the decision for the production of the 214 was made in 1955. By the time the production ended in 1960, a small series of 21 aircraft was produced (excluding the two prototypes.) Many sources state that around 20 were built but, according to Č. Janić. and O. M. Petrović, 21 were built (18 214AC and 3 214F). The problem with determining the exact number of produced aircraft lies in the fact that, in some sources, the three produced 214F include the prototype which was modified for this role. Despite the fact that the production began during 1957 (by Ikarus), the whole process was slow and, by the 1st of January 1959, only six 214 were built. Only one was built in 1957 and an additional five during 1958. By January 1st 1962, there were 21 aircraft in service with the Yugoslavian Air Force, with 17 fully operational. In the following years, there were no accidents and an average of between 15 and 18 were fully operational at any given time. In order to increase the 214’s operational service life, one additional factory (Vazduhoplovno-Tehnicki Remontni Zavod) was opened in Zagreb for the production of spare parts and repairs. The Ikarus factory, due to its  involvement  in other projects, was  exclusively involved in the production of spare parts from 1962 to 1964.

Due to the small numbers built, the 214 had only a few different variants.

  • 214P and 214D prototypes – Two prototypes built and tested with different engines.
  • 214F – 3 built as photo-reconnaissance planes. 
  • 214AC (214P)Main production version. 18 were built as trainer/passenger planes.
  • 214PPOne production aircraft was modified for anti-submarine operation.
  • 214AM-2One production aircraft was modified as an improved anti-submarine variant.

Conclusion 

Despite not being a successful design, the 214 did see operational use in the Yugoslav Air Force. As only small numbers were built, the model’s role was limited. The 214’s greatest success was that it helped rebuild the destroyed Yugoslavian aircraft industry and the designers and engineers gained additional experience in working with more modern aircraft designs.

Ikarus 214 Specifications

Wingspan 53 ft 2 in / 16.2 m
Length 38 ft 9 in / 11.2 m
Height 13 ft  / 3.95 m
Wing Area 320 ft² / 29.8 m²
Engine Two nine cylinder air-cooled P&W R-1340-AN-1 with 600 hp
Empty Weight 3,740 lbs / 3,970 kg
Maximum Takeoff Weight 11,080 lbs / 5,025 kg
Fuel Capacity 780 l
Maximum Speed 227 mph / 365 km/h
Cruising speed 186 mph / 300 km/h
Range 670 mi / 1,080 km
Maximum Service Ceiling 23,000 ft / 7,000 m
Crew One pilot and One copilot
Armament
  • Three 7.92 mm MG-15 Machine Guns
  • Bomb load of four 50 kg bombs

Gallery

Illustrations by Carpaticus

Ikarus 214
Ikarus 214AM-2 Anti-Submarine Variant
Ikarus 214 in Civilian Service

Credits

 

Ikarus MM-2

Yugoslavia flag Yugoslavia (1939)
Prototype Advanced Trainer – 1 Built

The MM-2 prototype had an unusual color scheme with a combination of red and polished aluminum.

With the emergence of new fighter planes in the years leading up to the Second World War, it became necessary to replace the older biplane trainer aircraft, which were too slow, in order to efficiently train new pilots to fly the newest fighters. Thus, it was logical that more modern advanced trainer aircraft would be needed. The MM-2 was an experimental Yugoslavian solution to this problem.

First Steps

At the end of the thirties, the Yugoslav Air Force was equipped with modern planes, such as the German Me-109, the indigenous IK-3, and the British Hurricane, highlighting the need for an updated trainer. There were several older aircraft in use for the role, like the FP-2 and the Rogožarski PVT, with a maximum speed of around 140 mph (230 km/h) but there was a need for a much faster and modern aircraft trainer.

The designer of the MM-2 trainer, Captain Dragutin Milošević.

To fill this gap, Air Force engineer and pilot Captain 1st Class Dragutin Milošević, on his own initiative, began to work on a new advanced trainer in 1936. The first aerodynamic calculations, choice of engine, structure, and the design were done by 1937. This new plane was conceived as a two-seater with seats one behind the other, with an enclosed cockpit and dual controls. It had a low wing, mixed construction, with a single engine and retractable landing gear. The engine would have been the Renault 6Q-02, giving 162 kW (220 hp). Milošević never gave a designation for this plane, but was later simply named the M-1.

Captain Dragutin Milošević submitted this project to the Yugoslav Department of Aviation in 1937. The Department analyzed this proposal and, while on paper it would have had great flying performance, a decision was made to reject it because the parts necessary for its construction had to be imported from abroad.

This decision did not discourage Captain Milošević, and he made attempts to improve his design. He proposed replacing the Renault with the license-built Gnome-Rhone K-7 309 kW (420 hp) air-cooled 7-cylinder engine. By adding this engine, the length of the plane would be reduced from 23 ft 7 in to 20 ft 4 in (7.2 m to 6.7 m) but the total weight increased to 2,160 lbs (980 kg). To improve the landing characteristics of the aircraft, it would have been necessary to increase the distance between two front landing wheels from 6 ft 2 in to 7 ft 10 in (1.9 m to 2.39 m). All aerodynamic and statistical calculations were finished by 1939. The second version was named M-2 and it was, in essence, the basis of the future MM-2 aircraft.

One wooden model (1:10 scale) was built by the Albatros factory in Sremska Mitrovica. This model would be used to test the aerodynamic properties and accuracy of earlier calculations. Aerodynamic properties were tested in the Paris wind tunnels on the 17th and 18th of July 1939. After these trials, the fuselage length reverted to the original 23 ft 7 in (7.2 m).

Later, Captain Milošević did new calculations that showed that certain changes to the design of the aircraft were necessary. Adding weapons and increasing fuel capacity would lead to an increase of the mass of the M-2 by 242 lbs (110 kg), some 60 lbs (30 kg) in fuel and 176 lbs (80 kg) in armament. After all the other modifications, the total mass reached 2,782 lbs (1,262 kg) compared to the initial 2,160 lb (980 kg). The wing area had to be increased from 129 to 146 sq ft (12 to 13.6 m²) and the wingspan from 27 ft 10 in to 30 ft 3 in (8.5 to 9,23 m).

Adoption of a Prototype

Captain Milošević submitted a letter, together with documents, plans and calculations, to the supreme headquarters of the Yugoslavian Air Force, notifying them of the test results of the proposed M-2 aircraft. Since he did not receive any kind of response, he asked Major Đorđe Manojlović, also an aviation engineer, for help. Although Đorđe Manojlović did not have a direct impact on the design of the M-2, his great influence and connections in the Supreme Air Force Command lead to the continuation of the project. The cooperation of these two men lead to the final approval for construction of the M-2 aircraft project.

The only MM-2 prototype during its construction by Ikarus.

When the Air Force Headquarters of the Army of the Kingdom of Yugoslavia accepted the M-2, construction of this project was given to the Ikarus factory. The contract was signed on the 25th March 1940. It was planned to build one prototype aircraft for testing in order to ascertain if the M-2 was fit to be accepted for serial production. The project was monitored by a team composed of engineer Sava Petrović, Air Force Major Vojislav Popović and the technician Stefan Lazić. The prototype was ready by the first half of November 1940.

Origin of the Name

In the Kingdom of Yugoslavia, there was a custom of using the initials of the names of the designers as the official designation for most of new types of aircraft in service (like the IK-2/3), and MM-2 was no exception. MM comes from the initials of the surnames of Captain Dragutin Milošević and the constructor and engineer Major Đorđe Manojlović. There is sometimes confusion about the exact name of this aircraft. It is sometimes also called MiMa-2. In some documents found after the war, it is also called M.M. 2. In this article, the MM-2 name will be used, as it is the most common.

Technical Characteristics

Captain Dragutin Milošević’s first drawing of the MM-2. Note that the engine nose design appears to be for an inline engine, different from the actual prototype.

The MM-2 was designed as an advanced two-seater trainer, with seats one behind the other, with dual controls and a fully enclosed cockpit. It was a low wing, mixed construction, a combination of wood and metal, single engine aircraft with retractable landing gear.

The wings had a trapezoidal shape with a rounded top. They were constructed by using two racks which were made of steel tubes welded together. The racks were welded to the plane’s hull and the wooden ribs were connected to them by rivets. The wings were covered with canvas, except for the central parts, which were made of aluminum sheet. This was done so that the technicians and repair crews could have easy access to the inside of the wing. The ends of the wings were made of wood that were held in place by steel fittings. The flaps were covered in canvas and operated either manually or hydraulically.

The MM-2 hull was of mixed construction. The main body was made by using welded pipes. The front part was covered with aluminum sheet and the rear with canvas. The tail was made mostly of wood and covered with canvas.

The main engine was the Gnome-Rhone K-7, which supplied 310 kW (420 hp). It was domestically built under license from Franch aircraft manufacturer Rakovica. It was hoped to use a two-bladed metal propeller but, due to the lack of resources, wood was used. The maximum estimated speed (never achieved) was around 250 mph (400 km/h), with an effective range of 475 mi (764 km) with some 40 gallons (150 l) of fuel capacity. Climbing to 6,500 ft (2,000 m) could be achieved in 3 minutes and 9 seconds, but the maximum service ceiling was never adequately tested.

The landing gear was supposed to be of the ‘Nardi’ type imported from Italy, but it was planned to domestically build the landing gears for the production version, to avoid being dependent on foreign countries. On the prototype, no radio was installed but it was hoped to equip all future production aircraft with the FuG VII radios.

The main armament consisted of two wing-mounted 7.7 mm Darn-type machine guns with 175 rounds of ammunition for each gun. The total bomb load consisted of four 10 kg bombs carried under the wings. It must be noted that the armament was never installed on the prototype, as testing was interrupted by the beginning of the war.

First Test Flights

MM-2 Side View

The first test flights were made by the beginning of the 1941 at the Zemun airport. The pilot for these flights was Vasilije Stojanović, the test pilot of the Ikarus factory. By the end of March 1941, some 45 flights had been made with a total of 20 flying hours. The pilot assessed the flying performance of this plane as excellent. The results of these tests indicated that this aircraft had good flight performance. The controls were adequate, both instructor and the students cockpits had enough room with a good field of view and, during flights, the aircraft did not present any tendencies for sudden unpredictable movements. Due to its good air brakes and flaps, take-offs and landings were quite easy. There were no major objections from the test pilot about the MM-2.

The MM-2 could very easily reach speeds of up to 217 mph (350 km/h). The design maximum speed was never tested, but calculations suggested that it could be as high as 250 mph (400 km/h). This was never confirmed due to the outbreak of the war. The MM-2 prototype had an unusual color scheme with a combination of red on most of the rear fuselage and wings, and polished aluminum on the majority of the fuselage and the engine section, with a small Yugoslav flag painted on both sides of the tail.

On the 25th of March 1941, a contract was signed between Ikarus and the Air Force. According to this contract, Ikarus was to prepare for production of MM-2 trainer planes in the near future. Before the production would begin, a last series of tests was to be conducted by a test group at an airfield near city of Kraljevo. An order was given to Stojanović to fly the MM-2 from Zemun to the Kraljevo airfield. Once there, it was planned to do some more flight performance trials in order to examine the limit of the flying characteristics of the MM-2 aircraft. Stojanović completed the flight on the 4th April. Final production was never achieved due to the German invasion of Yugoslavia that started only a few days later.

Operational Service

The MM-2 did not see any active service in the Royal Yugoslav Army because of the beginning of the April war, the German attack on Yugoslavia in April 1941. After the defeat of the Yugoslav army, the Independent State of Croatia, or NDH, was created. In order to form the new NDH military air force, it was necessary to find and obtain planes to equip these new units. Like many other former Yugoslav planes, the MM-2 was also pressed into NDH service in a very limited role.

It seems that the MM-2 had some engine problems (possibly sabotaged) when it was captured by the Germans at airfield near Kraljevo. It is possible that it was in a bad condition since the Germans did not even bother to repair it and put it into operational use.

The MM-2, together with other Yugoslav captured aircraft, was collected and handed over to the NDH. After a while, the MM-2 was repaired under code name No. 6301, and returned to active service. Additional flight tests were conducted by Georgije Jankovski, a test pilot for Dornier-Werke. In September 1941, the plane was transferred to the Zemun airport and handed over to Croatian Major Ivan Pupis for future use. Major Pupis was the leader of the group responsible for the repair, reception and later transfer of all Yugoslavian aircraft captured during the April war. When the MM-2 was repaired and ready for active service, Pupis to keep it for his personal use rather than handing it over to the military.

On the May 13 1942 pilot Vid Saić, he lost control of the aircraft and crashed due to inexperience. The MM-2 was deemed too complicated and expensive to repair.

The MM-2 was ‘owned’ by Pupis until March 23rd, 1942, when he received a direct order from the Croatian Aviation Command to transfer the MM-2 to the ‘Rajlovac’ airfield near the city of Sarajevo in Bosnia. The aircraft arrived at the beginning of April 1942. The MM-2 was given to the 17th Squadron (Jato) which was part of the 6th group (Skupina) under the Command of the Major Romeo Adum. The MM-2 was used mostly for limited test flights. On May 13, 1942 while piloted by Vid Saić (from the 18th Squadron), the plane crashed. The pilot survived the crash with no injuries. A commission was formed to investigate the causes of the crash and found several irregularities: The pilot did not ask for permission and had no orders to fly on the MM-2 that day, and he also did not know anything about the flying characteristics or the condition of the plane. The conclusion was that the pilot was guilty for the accident and, as punishment, Vid Saić lost his Pilot rank. The damage to the MM-2 was estimated to be around 90%. There was no point to try to rebuild it from scratch and the remaining parts were destroyed. There is no information whether it was equipped with any armament in Croatian military service.

Production

Due to the outbreak of war on April 6th, 1941, except for the prototype, no other specimen of this aircraft was ever built. In some documents and letters found after the Second World War, it was discovered that the Ministry of Aviation planned to order around 50 copies of the MM-2 aircraft. Along with this, the Yugoslav military negotiated with Germany for the purchase of Arado Ar 96 training planes, but nothing came of this.

After the war, the new communist Ministry of Aviation and the Ikarus factory representatives were also interested in restarting the production of this aircraft but, as the chief designer had died in one of the many German prison camps and the necessary machines and tools were lost during the war, this was too difficult and was abandoned.

Operators

  • Kingdom of Yugoslavia – Built and tested the single prototype.
  • Independent State of Croatia NDH – Used the MM-2 captured during the April war, but it was lost in an accident.

MM-2 Specifications

Wingspan 30 ft 6 in / 9.23 m
Length 23 ft 7 in / 7.20 m
Height 9 ft 6 in / 2.89 m
Wing Area 14.6 ft² / 13.60 m²
Engine One Gnome-Rhone K-7, 309 kW (420 hp) air-cooled 7-cylinder engine
Empty Weight 1,071 lbs / 894 kg
Maximum Takeoff Weight 2,290 lbs / 1,330 kg
Fuel Capacity 150-160 l
Maximum Speed 250 mph / 400 km/h
Cruising Speed 390 mph / 630 km/h
Range 475 mi / 764 km
Maximum (estimated) Service Ceiling 6,600 ft / 2,000 m
Climb speed Climb to 2,000 m in 3 minutes and 9 seconds
Crew Two, instructor and student pilot
Armament
  • Two Darn M30 7.7 mm machine guns in wings
  • Total bomb load around 40 kg.

Gallery

Illustration by Haryo Panji https://www.deviantart.com/haryopanji

Ikarus MM-2 Side View [Haryo Panji]
MM-2 Front View
MM-2 Rear View

Sources