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|  The general concept of the plane was conventional for this period :  a cantilever monoplan type wing fitted low and a front pull engine meant the best technical mix for a high-performance plane. The low wing allows for a shorter (and lighter) main landing gear altogether with an excellent visibility in flight for the pilot. The cockpit was spacious and the canopy was built with no framework, which was a true innovation in 1938 ! The engine of the prototype was the BMW139, an 18 cylinder engine (two stars of 9 cylinder). This engine was chosen first for its robustness and its capacity to sustain damage, and it was also chosen for its impressive 1550HP. That is more than the better in-line engine of the time ! K. Tank has never regretted this choice because the strength of the radial engine was proven all along WW2 and many pilots from both sides flew back home despite severe engine damage. RLM's requested easy production in order to reduce production costs, a good accessibility for maintenance, and the possibility to sub-contract the making of some of the engine's systems.  The FW190 was designed by a light team of engineers, who worked quickly in narrow collaboration and under sway of Rudolf Blaser, manager of the project. A good example of the team's frame of mind is the landing gear. It was designed to withstand a vertical speed of 5m/s (16,5 ft/s) instead of the 2,5 m/s (8,2ft/s) that had been specified. Only minor modifications were necessary throughout the several evolutions of the fighter between the first and the last versions produced at end of the war. These brought the Fw190 from 6600 lbs to more than 11000 lbs at maximum weight !  Most of the structural parts were clearly stronger that what specifications required. The excellent flight manoeuvrability of this fighter was due to its control surface, well sized, statically and dynamically balanced, operated by rigid rods (instead of the usual control cables) providing a quick and precise response to the pilot' commands. The others team members were OB. Ing Mittelhuber for quality control, OB. Ing Willy Käther for design, the test pilots were Dipl. Ing Francke, Beauvais and Thoenes. The Chief pilot was Hans Sander. (I haven't found yet the names of the other persons on the team).
The BMW801 engine have also cooling problems, but they were quickly brought back in acceptable limits. These problems were entirely solved after many modifications (variant A, then C-0, C-1 and C-2) and the adoption of the BMW801-D2 engine. Apart overheating and lubrification of the lower cylinders of rear star problems, the largest troubles came from the "Kommandogerät". This device would be discharge the pilot | ||||||||||||||||
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The prototype flew correctly despite of its chronic engine overheat problems. The first flight took place on the 1st June 1939 at Brême. The test pilot was Hans Sander. These overheat problems were never solved for the prototypes. Prior to the first flight of the prototype, the BMW firm suggested an other engine they had developed: the BMW801engine. 
hood and nose spinner. As a matter of fact, the imposing nose spinner provided a drag gain that was actually negligible and the engine were not better cooled. The BMW139 engine were then rapidly abandoned, the overheat engine problems being insoluble.
prototype were greatly modified in order to be fitted with the new BMW801C-0 heavier engine. Armours plating and diverse devices required by the Luftwaffe were also added. All these changes increased the total weight of the prototype up to 3400 Kg (7500 lbs) that is, 25% extra weight. The logical consequence was a wing load increase from 186kg/m² (38,1 lbf/ft² ) to 227 kg/m² (46.5 lbf/ft² ) and the manoeuvrability of the plane worsened. The production of the Fw190A-0 pre-serial version started at the same time as the production of the V5 prototype. The V5 was seriously damaged in a ground collision with a vehicle. During the repairs some modifications were undertaken on the wing and tail. The wingspan was increased 
and the sweep-wing decreased, the wing area was therefore 22% increased, and the V5 was renamed "V5g" ( for "grosser", bigger in German ) and the V5g regained its original manoeuvrability some two first prototypes despite of the weight increase. The V1 to V8 prototypes were all built with the "small wing" renamed V5k, wing area of 14,9m² (160,4 ft²). From the V7 prototype onwards, all fighter were equipped with the new V5g wing, that had a wing area of 18,3m² (197ft²).
from mixture adjustments, propeller pitch adjustment, admission pressure regulation, etc in short, just a throttle control lever and the device dealt all, in theory...! In practice, this device was sensitive and very delicate to set. Another problem was the inopportune release of the compressor in the surrounding 2600 meter of altitude and of the sharp variations of the step of the propeller packing the engine. The BMW firm was commanded by K.Tank itself (after a tumultuous flight test) to re-examine its capricious device. At his line operation putting, the Fw190 showed the founded good ideas of K.Tank and outclassed all the fighter in service including is famous rival, the Spitfire MkV. The FW190 went up better than its rival and entered in turn more quickly than this one! and this situation will continued approximately one year until the product of Spitfire MkIX. Thereafter, the successive technical evolutions have permit at the Fw190 to remain an formidable adversary until the end of the conflict with the last D9 versions and beyond.){kind=link}