War horse – early development of the Fw 190
Early development of the Fw 190
Focke-wulf was contracted to develop a front line single-seat fighter to operate alongside the Messerschmitt Bf 109 in 1938 and designer Kurt Tank was determined that it would be a ver y different breed from its stablemate.
When Willy Messerschmitt created the Bf 109 in 1934 there was very little else in the world to match its simple yet highly efficient design. It wasn’t perfect but it surpassed its contemporaries in almost every respect. By the time Kurt Tank and his team came to design the Fw 190 in 1938, the Bf 109 had seen action in the Spanish Civil War and its imperfections had become readily apparent. The Germans had also become increasingly concerned about the British Supermarine Spitfire. It was feared, with some justification, that this advanced fighter was already able to outperform the Bf 109. Therefore, Tank set out to develop an aeroplane that would not only address the Bf 109’s flaws but also have a reasonable chance of besting the Spitfire – a tall order. It helped that Tank was given leave to examine production Bf 109 machines up close and in detail before getting started. Describing the design philosophy behind the Fw 190, Kurt Tank told aviation historian Dr Alfred Price: “The Messerschmitt 109 and the British Spitfire, the two fastest fighters in the world at the time we began work on the Fw 190, could both be summed up as a very large engine on the front of the smallest possible airframe; in each case armament had been added almost as an afterthought. “These designs, both of which admittedly proved successful, could be likened to racehorses: given the right amount of pampering and an easy course, they could outrun almost anything. But the moment the going became tough they were liable to falter. “During the First World War, I served in the cavalry and in the infantry. I had seen the harsh conditions under which military equipment had to work in wartime. I felt sure that a quite different breed of fighter would also have a
place in any future conflict: one that could operate from ill-prepared front line airfields; one that could be flown and maintained by men who had received only a short training; and one that could absorb a reasonable amount of battle damage and still get back. “This was the background thinking behind the Focke-wulf 190. It was to be not a ‘racehorse’ but a Dienstpferd, a cavalry horse.” The Fw 190 would be tough and dependable but it would also have to be able to keep up with the ‘racehorses’ where it mattered. The airframe would be sturdy enough to carry heavier weapons than the Bf 109 could manage but not so heavy that it incurred a performance penalty. The need for good all-round visibility was also a key consideration. The Bf 109’s cockpit canopy featured heavy frames and the rearward view was less than satisfactory, therefore Tank’s team came up with a sloping frameless ‘bubble’ canopy. For the powerplant, an air-cooled radial engine was chosen because it could soak up battle damage without failing – where a damaged liquid-cooled unit might rapidly run dry and seize – and because Tank already had one in mind, the 14-cylinder BMW 139. With Junkers’ Jumo 210 design reaching the limits of its potential, its follow-on the Jumo 211 being fitted to the Ju 87, Ju 88 and Heinkel He 111 and Daimler-benz’s DB 601A already earmarked for the Bf 109 and Bf 110, it also made sense to choose an engine that was not committed elsewhere. The BMW 139 was designed with two rows of seven cylinders positioned back to back. Compared with an inline design such as the DB 601, it had a higher power to weight ratio but at the cost of generating an enormous amount of heat in a small area. Tank said: “So the air-cooled radial engine was fitted to the Fw 190. When the fighter went into action the resilience of this type of power plant was proved again and again. There were several occasions when these fighters returned home and made normal landings, having had whole cylinders shot away. “Once its cooling system had been pierced and the liquid allowed to drain away, the running life of the equivalent liquid-cooled engine would have been about three minutes.” With all these requirements in mind, Tank’s design team submitted a series of
designs to the RLM. One of them was chosen and Focke-wulf was given an order to proceed with the construction of prototypes. In working out how to build the Fw 190, Tank’s team decided that simplicity was critical. The engine was attached directly to the monocoque fuselage, avoiding the need for engine mounts, and two removable selfsealing fuel tanks were fitted directly beneath the pilot. The smaller tank, of 232 litres, was below the pilot’s legs and the larger, of 292 litres, was directly behind it under and behind his seat. This gave the Fw 190 more than twice the fuel capacity and therefore twice the range of the Bf 109, which could only carry 250 litres internally. The wings, featuring split flaps, were built as a separate piece and a series of ridges and corresponding grooves allowed them to be quickly moved into the correct position on the fuselage when fitted. After the trouble caused by the hydraulically operated undercarriage on the Fw 159, the Fw 190 used a straightforward and reliable system of cables that were electrically wound in or out on drums to raise and lower its main and tail wheels. The only exceptions were the first two prototypes, which both had hydraulic systems. The Bf 109 had a narrow track undercarriage where the bulky wheels retracted outwards into the wings, restricting what weapons could be fitted there. In contrast, the Fw 190 had a wide track and the wheels retracted inwards under the fuselage, reducing intrusion into the wings and freeing up space. The first armament arrangement to be fitted was two machine guns and two cannon – a 7.9mm MG 17 with 800 rounds and a 20mm MG 151 with 160 rounds in each wing, close to the fuselage. Ease of maintenance was another consideration in the Fw 190’s design. Components that would require frequent servicing were positioned within easy reach and large access panels were provided to make the technician’s job easier. Climbing aboard the fighter, which stood nearly 4m tall at its highest point compared to the Bf 109’s relatively diminutive 2.6m, was made easier with the addition of a retractable step which popped out of the lower edge of the fuselage on the port side aft of the wing root. Then there was a spring loaded handhold and a further step. Inside the cockpit, the seat was semireclined and vertically adjustable over a range of 4in. A lot of work was done to ensure that instruments were laid out in a logical way, with everything easily to hand. A 1000W generator provided internal systems with a 24v power supply. The fuel-injected BMW 139 engine, which developed 1500hp on takeoff, drove a threebladed Vereingite Deutsche Metallwerke electro-hydraulic variable pitch propeller measuring 3.4m in diameter. Over this was fitted a large Doppelhaube ducted spinner intended to reduce drag and, it had been calculated, improve the aircraft’s top speed by about 25mph. As with all of Tank’s previous Focke-wulf aircraft, while he set the Fw 190’s design parameters and oversaw the project, the detailed design was down to his team. The work was coordinated by his assistant Willi Käther, engineer Rudolf Blaser designed the structure and test pilots Hans Sander and Kurt Melhorn both contributed from an early stage. A wooden mock-up was constructed to begin with, during the autumn of 1938, then work was started on the prototype, Fw 190 V1. The ‘V’ stood for ‘Versuchs’ or ‘experimental’. The first flight of the finished product took place on June 1, 1939, with Sander at the controls. While he was impressed by the aircraft’s performance, he found another aspect of the flight less satisfactory: “For the first flight, I wore only a thin flying suit over my normal underwear, socks, ordinary shoes, and a flying helmet with my oxygen mask hanging loose, yet soon after takeoff I began to sweat profusely. “The rear of the engine was hard up against the front wall of the cockpit, and my feet and rudder pedals were either side of the engine accessories. The temperature in the cockpit rose to 55ºc. I felt as though I was sitting with my feet in the fire. The heat was bearable but ever since I have had some sympathy for a steak on a grill.” Sander also had to put his oxygen mask on because engine exhaust fumes were beginning to leak through the improperly sealed edges of the canopy. Despite these problems, the test was deemed a success. The Fw 190 V1, given the civil registration D-OPZE, was shown to Adolf Hitler, Hermann Göring, Ernst Udet, Erhart Milch and General Wilhelm Keitel just over a month later on July 3, 1939. At this stage it had no armament fitted and there was a problem with the V1’s hydraulic undercarriage up-lock mechanism. The landing gear would rise and lock correctly after takeoff but then, during aerial manoeuvres, the oleo legs would become unlocked and sag down. This was eventually fixed by fitting a new stronger mechanism based on a bomb release shackle.
As tests continued, cooling problems persisted and Focke-wulf’s Doppelhaube spinner was identified as the source of the problem by BMW. Focke-wulf kept the spinner however, for the aerodynamic reasons previously stated. A test pilot from the Reichlin experimental centre, Heinrich Beauvais, visited Focke-wulf on October 31, 1939, to make a formal assessment of D-OPZE, which was now being re-registered as FO+LY under a new system being implemented across Germany. He later wrote: “We instinctively preferred the Fw 190 over the Bf 109 from the very
start. The reasons for this are detailed in our report. The Fw 190’s control forces are significantly lower at high speeds, and its rate of roll is markedly greater. “Furthermore, its wide-track undercarriage and the superior rigidity of its airframe are highly thought of, especially in belly-landings. The view to the rear is superior, and its BMW radial engine is less vulnerable to enemy fire. “There was a tendency to disbelieve its inferiority in turning. Our report states that: ‘It has yet to be determined whether the Fw 190 turns tighter than the Bf 109’. In my opinion this should be viewed as misleading. “It is true that turning radii were not measured, but that did not really matter. What did matter was turning times, and in this respect the Bf 109 was clearly superior. However, it needed barely four seconds to perform a complete roll, compared to five seconds for the Bf 109.” On the same day the Fw 190 V2, registered as FO+LZ, made its first flight with both machine guns and cannon installed. It also had a FUG VII radio and Revi C/12C gunsight fitted. Around this time the Fw 190 was given its Focke-wulf bird name; following on from the tradition established by the Stieglitz, Stösser, Weihe and the rest it was called Würger (Shrike). Two months later, after suffering from the same overheating problems as FO+LY, the V1, it also had a new 10-bladed cooling fan fitted beneath its spinner. This helped a little but failed to cure the problem. BMW persisted with its claim that the spinner was the problem and Focke-wulf finally relented. Comparative tests were conducted in January 1940 using the two prototypes with Fw 190 V2 retaining its Doppelhaube while V1’s was removed and
replaced with a straightforward Naca-style cowling of BMW design. These trials revealed that far from added to the Fw 190’s top speed, the spinner was actually slowing it down by about 12mph. In fact, Focke-wulf had failed to account for the inch-wide gap between the spinner and the engine cowling, which caused air to be sucked through the propeller hub causing drag. The Doppelhaube concept was scrapped and all future Fw 190s had a Naca-style cowling instead. With its new cowling in place, V2 was flown in a personal demonstration for Göring and an order for 40 pre-production aircraft, known as the Fw 190A-0, followed. V2, now re-registered again as RM+CB, was damaged in an accident on March 2, 1940, when it flipped over on to its back during taxiing. Repaired, it was used for weapons trials starting in September 1940. V1 was taken to Rechlin for further flight trials on June 11, 1940. Unfortunately, the overheating problems of the BMW 139 had proven to be incurable and the engine design was scrapped after just 47 units had been produced. Work on Fw 190 V3 and V4, which were nearing completion with fittings prepared for the 139, was halted. V3 was cannibalised for spares and V4 was load tested to destruction. The loss of the BMW 139 was not a disaster for the Fw 190 however, as the engine manufacturer had been working on a similar model in parallel which was specifically designed for fan cooling, the BMW 801 C. In fact, the 801 incorporated elements of both the BMW 139 and an engine designed by Bramo, a rival firm which BMW had absorbed in 1939 – the Bramo 329. The 801 C was roughly the same diameter as the BMW 139 and slightly longer but it promised to be even more powerful, more reliable and significantly less prone to overheating than its predecessor. It was also heavier. Another change was the addition of a device known as the Kommandogeräte. This clever mechanism automated the adjustment of manifold pressure, compressor gear shift, fuel mixture regulation, ignition control and constant speed control through propeller pitch. Kurt Tank said: “In theory, the Kommandogeräte meant that the pilot only had to move one control, his throttle. I say ‘in theory’, because at first the device did not work at all well. All sorts of things went wrong with it. One of the more disconcerting things was the rather violent automatic switching in and out of the high gear of the supercharger as the aircraft climbed through 2650m.
“On one occasion I was carrying out a test with an early version of the Fw 190 which involved a loop at medium altitude. Just as I was nearing the top of the loop, on my back with little airspeed, I passed through 2650m and the high gear of the supercharger cut in with a jerk. “The change in torque hurled the aircraft into a spin with such suddenness that I became completely disorientated. And since there was a ground haze and the sky was overcast and my artificial horizon had toppled, I had no way of knowing which way was up. “After a lot of trial and error, and a considerable loss in altitude, I managed to recover from the spin. But the incident had given me a lot to think about.” Tank contacted BMW immediately on landing and demanded that the Kommandogeräte be fixed. BMW’S engineers continued their development work on the device and its problems were gradually ironed out. The first prototype fitted with the BMW 801 C, Fw 190 V5, first flew in April 1940. The extra weight of the engine, another 150kg, meant that the Fw 190’s airframe had to be strengthened to accept it and the undercarriage struts had to be stiffened. Due to the larger structure needed to accommodate the engine, the cockpit was moved slightly further aft and the overall length of the aircraft was increased by 6.8cm from 8.73m to 8.798m. With the pilot now further away from the engine, the cockpit remained cooler and the extra space at the front of the aircraft was just enough to allow a pair of machine guns to be fitted on to its nose above the engine if required. Earlier tests had revealed that above 270mph the Fw 190’s emergency canopy release mechanism was non-functional. Air-flow over aerodynamic hood held it firmly in position, preventing the pilot from baling out. A bungee cord system and compressed air was tried before it was calculated that in order to overcome the external pressure, a force equivalent to 50hp was needed. Designer Rudolf Blaser finally came up with a mechanism where a 20mm explosive cartridge pushed a piston which in turn
punched the canopy rearwards to the point where the airflow caught it and whipped it smoothly away from the airframe. Inspired by this innovation test pilot Sander, who was also a qualified engineer, came up with a primitive ejection seat mechanism for the Fw 190 but he was unable to give the project his full attention and when his initial efforts demonstrated that the explosive cartridges available were not powerful enough to propel the pilot far enough to avoid the aircraft’s tail the idea was dropped.
FW 190A-0 AND A-1
The extra weight of the BMW 801 C engine coupled with the heavier structure required to cope with it, and the other modifications, had a direct impact on the Fw 190’s manoeuvrability. The wing loading had increased and flight tests using V5 quickly revealed the impact this had on the aircraft’s handling. It was decided that the best way to reduce wing loading back to acceptable levels and restore the much admired handling of the Fw 190 V1 and V2 was to simply extend the wings. While this work was being discussed, prototype V6 was completed and took its first flight on May 31, 1940. It suffered from problems with its BMW 801 C however and made just nine flights before the original unit had to be swapped for a new one. Both V5 and V6 each armed with a quartet of 7.9mm MG 17 machine guns – two in the wing roots and two on the nose. This configuration meant that they were retrospectively referred to as Fw 190A-0/U1S. The ‘U’ stood for ‘Umrüst bausatz’ or ‘conversion kit’ – an ‘Umbau’ was a change to the aircraft’s configuration that could only be carried out at the factory or on rare occasions in the field by an accredited Focke-wulf subcontractor. After the two Fw 190A-0/U1 aircraft a series of nine more A-0s were produced, taking their first flight between July and October 1940 and being used to test various different weapons layouts, engine modifications and other experimental alterations to the aircraft’s design. Finally, on October 10, 1940, Fw 190A-0 WNR. 0016 (the 16th Fw 190 built after the six ‘Versuchs’ aircraft and the nine A-0s), coded KB+PR, made its flying debut with an enlarged wing. Each wingtip had been extended by just over 50cm, giving it a wingspan of 10.5m, compared to 9.5m of all the earlier examples. Wing area was correspondingly increased from 14.9sq m to 18.3sq m. The amount the wing tapered was also reduced so that the wingtip itself took on a squarer look. In later versions of the Fw 190, the area of the tailplane was also increased. Performance was still worse than the smallwing BMW 139 Fw 190s however, with top speed at 18,372ft down from 432mph to 426mph and range down to 671 miles from 684 miles. Service ceiling was improved though, from 36,090ft to 37,400ft. The new wing was thereafter referred to as the V5g and Fw 190s without it were V5ks, the ‘g’ being for ‘grosser’ (larger) and the ‘k’ being for ‘kleiner’ (smaller), and was installed on all subsequent Fw 190A aircraft. In early 1941, WNR. 0007 became the prototype for the Fw 190A-1 and was given the new production WNR. 190.0110.001. The 190 was the type, the 011 meant ‘A-1’, the 0 was the manufacturer – Focke-wulf – and the 001 was the individual aircraft’s serial number. Other companies that later built the Fw 190 had their own numbers where Focke-wulf had the 0. Ago had 2, Arado had 5 and 6 and Fieseler had 7. As the template for the front line fighters that were to follow, WNR. 190.0110.001 had a BMW 801 C-1 engine generating 1560hp at sea level, a pair of MG 17s over the engine and two more in the wing roots. There was also provision for the fitment of two 20mm cannon in outer wing positions. Bremen was bombed for the first time by the RAF on three consecutive nights from January 1-4, 1941. A British Cabinet Office report given on January 2 after the first raid, which involved 148 bombers, suggested that it had been a great success with no British bombers lost. While the brunt of the attack was born by Bremen itself, with firestorms raging across the city, the Focke-wulf factory was also targeted and suffered damage. The first Luftwaffe unit to convert to the Fw 190 was the II. Gruppe of Jagdgeschwader 26 (II./JG 26). In March 1941, JG 26 officers Oblt Otto Behrens and Lt Karl Borris were seconded to establish and lead an experimental unit, Erprobungsstaffel 190, at Rechlin-roggenthin to ready the Fw 190 for active service with the Luftwaffe. Both men had technical backgrounds and they were given a team of 30 ground crew and half a dozen A-0s to work with.
Borris found the Fw 190 impressively robust and a pleasure to fly but realised that its BMW 801 C engine was the source of serious and ongoing problems. He said: “Whatever could possibly go wrong with it did. We hardly dared to leave the immediate vicinity of the airfield with our six prototype machines. “Oil lines ruptured. The heavily armoured oil cooler ring in front of the engine often broke. The bottom cylinder of the rear row seized again and again, since the oil pump and the cooling surfaces were too small. Leaking fuel lines left the pilots in a dazed state from the fumes, unable to climb out of their aeroplanes unaided.” Focke-wulf suffered a setback on the night of March 12/13, 1941, when the RAF sent 86 Vickers Wellingtons and Bristol Blenheim bombers to attack Bremen. The bulk of the force, the 54 Wellingtons, targeted the Focke-wulf factory and succeeded in destroying jig assemblies and part of the company’s design offices. The attack was not entirely unexpected however. It was by now clear that Bremen, being close to Germany’s north coast and easily located thanks to its position straddling the largest waterway in the region, the River Weser, was an easy target. As such, it would be hit repeatedly throughout the rest of the war. Plans had already been set in motion, however, to construct a large new Focke-wulf production facility nearly 600 miles further to the east – a 100 acre site at Marienburg, East Prussia, known today as Malbork in Poland. At the same time, much of the Luftwaffe’s strength was being drawn away to the east as preparations for the invasion of the Soviet Union, Operation Barbarossa, entered their final stages. By June 28, 1941, there were just two complete Jagdgeschwader (fighter wings) left in the west – JG 2 and 26. Between them they could field a total of 140 serviceable Messerschmitt Bf 109Es and Fs. In July 1941, despite ongoing engine difficulties which left some at the RLM wondering whether the Fw 190 programme should be discontinued, Behrens and Borris’ unit was moved to Le Bourget airfield near Paris to begin the conversion training of II./JG 26. It was a slow process due to the ongoing technical problems. Two of the new fighters were lost on August 7 when they suffered engine failures and crashed, another on August 9. BMW was reluctant to take responsibility and was struggling to make the radial in the series, the BMW 801 D, ready for service. The biggest problem the company faced was a lack of high quality metals which could be used to create heat-resistant allots. Engines frequently suffered severe heat damage after just a few hours in operation, necessitating a complete rebuild or replacement. Nevertheless, by the end of August the whole of II./JG 26 was working up on the Fw 190. The unit was then transferred to first Maldeghem and then Moorsele and Wevelghem in Belgium. The first loss of a Fw 190 on the front line was to ‘friendly’ fire on August 29 when anti-aircraft guns near Dunkirk opened up on 6./JG 26’s Leutnant Heinz Schenk. He was shot down and killed. By October, III./JG 26 based at Coquelles, near Calais, had also begun converting to the Fw 190 and it was this unit’s technical officer, Oblt Rolf Schroedter, who finally found a workable solution to the BMW engine’s overheating problems. After the usual round of failures suffered by the engines of Fw 190s III./JG 26 had been given, Schroedter collected up all the failed units and had them sent to his Gruppe’s repair shop. Examining all the failed engines together enabled Schroedter’s team to quickly identify the source of the problem. It was determined that the exhaust system was to blame and simply rerouting it reduced the temperature of the bottom cylinder of the rear row – thereby removing the single greatest source of engine failure on the Fw 190. Schroedter’s ‘quick fix’ was adopted as a factory modification and soon BMW 801 C and later D units could run to more than 100 hours without suffering crippling heat damage. From June 1941 to May 1942, Focke-wulf built a total of 101 Fw 190A-1 fighters. The next major upgrade, the Fw 190A-2, had been prepared and two subcontractors – Arado at Warnemünde and AGO at Oschersleben – were gearing up to produce it en masse. More than this, the Fw 190 had now become a front line fighting machine and was beginning to encounter enemy machines in the skies over France.
Test pilot Hans Sander fires up the engine of Fw 190 V1.the metal panel behind the BMW 139 engine’s exhausts has already become heavily blackened.
Focke-wulf chief designer and chief executive Kurt Tank seated in an Fw 190. While Tank approved the aircraft’s basic layout, he readily acknowledged that the detail design work and ongoing development was carried out by his team. A wooden model of the Fw 190 V1 built in 1938. It is marked up to show how the aircraft itself will be constructed. The almost-completed airframe of Fw 190 V1 at Focke-wulf’s Bremen factory.
The stirrup step of Fw 190 V1 remains unretracted in this side view of an engine run-up test. At this stage the aircraft has not been painted and remains in bare metal finish. The Fw 190 V1 with Doppelhaube spinner fitted over its VDM propeller. Based on wind tunnel tests it was calculated that the large ducted spinner would improve the aircraft’s top speed by 25mph.these failed to account for the necessary gap between the spinner and the engine housing – which caused so much drag it completely negated any aerodynamic benefits. Fitted with a conventional Bmw-designed Naca-style cowling, Fw 190 V1 no longer suffered additional drag from its Doppelhaube spinner but was still prone to overheating.
With its civil registration, D-OPZE, clearly visible on the underside of its wings, Fw 190 V1 comes in to land. Now fully painted, Fw 190 V1 prepares for yet another test flight. The tail wheel of Fw 190 V1 lifts off the concrete runway at Focke-wulf’s Bremen facility as a test flight gets under way. Chief of the Air Ministry’s technical office Ernst Udet, centre, discusses the Fw 190 with his chief engineer Rulof Lucht, left, a former naval aviator, and the chief test pilot of the Rechlin Luftwaffe test centre Carl Francke, right.
An unpainted Fw 190 V5 is wheeled across Focke-wulf’s Bremen facility. Shadowed in the background is an early Fw 189 Uhu. First flown in April 1940,V5 was the third Fw 190 prototype completed and the first to be fitted with the BMW 801 C.AS a consequence its fuselage is slightly longer than that of V1 and V2, and the cockpit is further back from the engine. The 10 blades of the cooling fan installed over the BMW 139 on Fw 190 V1 are clearly visible in this forward view. The technical officer of II./JG 26, Karl Borris, was both a pilot and a qualified engineer. He was hugely impressed by the Fw 190’s handling characteristics but soon realised that its engine was the source of serious ongoing difficulties.
The mighty 14-cylinder BMW 801 engine. Designed to feature a 12-bladed cooling fan from the outset, it was initially bedevilled with overheating problems like its predecessor, the BMW 139. A quartet of pre-production Fw 190A-0 aircraft.the machine in the foreground, WNR. 0010, managed 30 flights with its BMW 801 C-0 engine – more than most of its contemporaries. D-OPZE not only underwent a change of nose during its development, it also changed registration to the military code FO+LY. It made its first flight in this form on January 25, 1940.
This Fw 190A-1, WNR. 0110.098, was used to test the Fw 190’s ability to carry up to eight 50kg SC 50 bombs. Final assembly of Fw 190s on the Focke-wulf production line at Bremen.the large panels that allowed easy access to the BMW 801 engine are clearly visible. Eight Fw 190A-0s lined up for inspection. Closest to the camera is WNR. 0008.This aircraft was fitted with a pair of 7.9mm MG 17 machine guns above its engine, firing through the propeller, and two 13mm MG 131 machine guns in its wing roots. It was used for armament tests but had to have a new engine after nine flights, another after a further 12 flights and then another, 10 flights after that. One of the last few Fw 190A-1s built, WNR. 0110.0100 ‘Black 13’ was allocated to 5./JG 26 at Wevelgem, Belgium, in November 1941. It was written-off the following April when its pilot, Uffz. Mathais Säckel, ran out of fuel and was forced to make an emergency landing.
Completed and ready for delivery – production model Fw 190A-1/U1 WNR. 0110.067 TI+DQ. Its military code would be overpainted with unit markings following delivery. One of the first Fw 190A-1s delivered to a front line unit – in this case 6./JG 26 at Moorsele, Belgium, in July 1941. During its early days in front line service it was not uncommon to see a Fw 190 dowsed in foam after an engine fire. It was only after several months with the Luftwaffe that a solution to the overheating problem was finally discovered and mostly cured with a re-routing of the exhaust system.