The first prototype, the Fw 190 V1 (civil registration D-OPZE), powered by a 1,550 metric horsepower [PS] (1,530 hp; 1,140 kW) BMW 139 14-cylinder[citation needed] two-row radial engine, first flew on 1 June 1939.

During the first flight, the temperature reached 55 °C (131 °F), after which Focke Wulf's chief test pilot, Hans Sander commented, "It was like sitting with both feet in the fireplace.

[7] Even with the new engine and the cooling fan, the 801 suffered from high rear-row cylinder head temperatures, which in at least one case resulted in the detonation of the fuselage-mounted MG 17 ammunition.

This was an opportune time to rebuild it with a new wing which was less tapered in plan than the original design, extending the leading and trailing edges outward to increase the area.

[4] The first unit to be equipped with the A-0 was Erprobungsstaffel 190, formed in March 1941 to help iron out any technical problems and approve the new fighter before it would be accepted for full operational service in mainstream Luftwaffe Jagdgeschwader.

Had it not been for the input of Behrens and Karl Borris, both of whom had originally enlisted in the Luftwaffe as mechanics, the Fw 190 program might have died before reaching the front lines.

[13][14] The addition of new ventilation slots on the side of the fuselage further aided cooling, and with the widespread availability of the A-2 in the spring of 1942, the overheating problems were greatly reduced.

[15] The Fw 190 A-3 was equipped with the BMW 801 D-2 engine, which increased power to 1,700 PS (1,700 hp; 1,300 kW) at takeoff by improving the supercharger and raising the compression ratio.

Some A-4s were outfitted with a special Rüstsatz field conversion kit, comprising the fitting of a pair of under-wing Werfer-Granate 21 (BR 21) rocket mortars, and were designated Fw 190 A-4/R6.

Some A-5s were tested with the MW 50 installation: this was a mix of 50% methyl alcohol and 50% water, which could be injected into the engine to produce a short-term power boost to 2,000 PS (2,000 hp; 1,500 kW), but this system was not adopted for serial production, yet.

The additional weight of the new weapon systems required strengthening of the wheels, adding a reinforced rim to better deal with typical combat airfield conditions.

Other changes included an ETC 501 under-fuselage rack which was mounted on a lengthened carrier and moved 200 mm (7.9 in) further forward to help restore the center of gravity of the aircraft.

In contrast, the Daimler-Benz DB 601 engines used on the Bf 109 featured an advanced fluid-coupled, single stage, variable speed supercharger that provided excellent boost across a wide range of altitudes.

These included a pressurized cockpit which doubled the panes of glass in the canopy so that hot air could be forced between them to prevent icing, and the addition of the GM-1 nitrous oxide injection system.

Several problems were encountered during the machine's flight and ground trials, mostly caused by the pressurization system for the cockpit, and for this reason the first B-series testbed airframe was retired from active service in late 1942.

In the event, the D series was rarely used against the heavy-bomber raids, as the circumstances of the war in late 1944 meant that fighter-versus-fighter combat and ground attack missions took priority.

To keep the design as simple and as aerodynamic as possible, Tank used an annular radiator (the AJA 180 L) installed at the front of the engine, similar to the configuration used in the Jumo powered versions of the Junkers Ju 88.

Some late model Doras were also fitted with the broader-chord Ta 152 vertical stabilizer and rudder, often called "Big Tails" by the Luftwaffe ground crews and pilots, as seen on W.Nr.

Hans Hartigs recalled that only one of the first batch of Dora 9s received by the First Gruppe had methanol water injection, and the rest had a top speed of only 590 km/h (370 mph).

[40] Owing to the failure of multiple attempts to create an effective next-generation 190, as well as the comments of some Luftwaffe pilots, expectations of the Dora project were low.

[42][43] As it was used in the anti-fighter role, armament in the "D" was generally lighter compared to that of the earlier aircraft—usually the outer wing cannon were omitted so that the armament consisted of two 13 mm (0.51 in) cowling-mounted MG 131s, with 400 rounds per gun, and two wing root mounted 20 mm MG 151/20E cannon with 250 rounds per gun; all four weapons were synchronized to fire through the propeller arc.

[49] To help anti-aircraft artillery protecting the airfields to quickly identify friendly aircraft, the under-surfaces of the Würger-Staffel 190s were painted red with narrow white stripes.

Visible changes over the D-9 were the enlarged supercharger air intake on the starboard side cowling and the use of a wooden, broad-bladed VS 9 or 10 propeller unit utilizing three 9-27012 C-1 blades with a diameter of 3.6 m (11.8 ft).

Pilots reported that due to the large amounts of torque produced by the engine, they usually used the steering system during the takeoff run as it helped with the rudder movements.

[56] As noted previously, this aircraft is still in existence, painted in its original color scheme as Yellow 10 of 6 Staffel/JG 26, is thought to be airworthy and is currently located in the Flying Heritage Collection at Paine Field in Everett, Washington.

New armor was added to the bottom of the fuselage, protecting the fuel tanks and pilot, the engine cowling, and the landing gear mechanisms and outer wing mounted armament.

The Fw 190 F-8 differed from the A-8 model in having a slightly modified injector on the compressor which allowed for increased performance at lower altitudes for several minutes.

There were also several Umrüst-Bausätze kits developed for the F-8, which included the Fw 190 F-8/U1 long range JaBo, fitted with underwing V.Mtt-Schloß shackles to hold two 300 L (80 US gal) fuel tanks.

With the removal of the fuselage mounted MG 17s, an additional oil tank was added to support the BMW 801 D-2 engine's longer run times.

[64] As the Luftwaffe phased out older aircraft such as the Ju 87 in favor of the Fw 190, many pilots required flight training to make the transition as quick and smooth as possible.