Spitfire MK 3 with the Merlin XX easily the best fighter that could be built in 1940. It's got a. multi stage supercharger as well!
29 May 1940: Vought-Sikorsky Aircraft Division test pilot Lyman A. Bullard, Jr. took the U.S. Navy’s new prototype fighter, the XF4U-1, Bu. No. 1443, for its first flight at the Bridgeport Municipal Airport, Bridgeport, Connecticut. Designed by Rex B. Beisel, this would be developed into the famous F4U Corsair.
The F4U Corsair is a single-place, single-engine fighter, designed for operation from the U.S. Navy’s aircraft carriers. The XF4U-1 prototype was 30 feet (9.144 meters) long with a wing span of 41 feet (12.497 meters) and overall height of 15 feet, 7 inches (4.750 meters). It had an empty weight of 7,505 pounds (3,404 kilograms) and gross weight of 10,500 pounds (4,763 kilograms).
The XF4U-1 was first powered by an experimental air-cooled, supercharged, 2,804.4-cubic-inch-displacement (45.956 liters) Pratt & Whitney Double Wasp A2-G (R-2800 X-2), and then an SSA5-G (R-2800 X-4), both twin-row 18-cylinder radial engines. The R-2800 X-4 was an X-2 with a A5-G supercharger. It was rated at 1,600 horsepower at 2,400 r.p.m. at 3,500 feet (1,067 meters); 1,540 horsepower at 2,400 r.p.m. at 13,500 feet (4,115 meters); 1,460 horsepower at 2,400 r.p.m. at 21,500 feet (6,553 meters); and 1,850 horsepower at 2,600 r.p.m for takeoff. The engine drove a 13 foot, 4 inch (4.064 meter) diameter, three-bladed, Hamilton Standard Hydromatic constant-speed propeller through a 2:1 gear reduction. The X-4 had a compression ratio of 6.66:1 and used a two-speed, two-stage supercharger.
The XF4U-1 prototype had a maximum speed of 378 miles per hour (608 kilometers per hour) at 23,500 feet (7,163 meters). Although it has been widely reported that it was the first U.S. single-engine fighter to exceed 400 miles per hour (643.7 kilometers per hour) in level flight, this is actually not the case. During a flight between Stratford and Hartford, Connecticut, the prototype averaged a
ground speed 405 miles per hour (652 kilometers per hour). This was not a record flight, and did not meet the requirements of any official speed record.
Fuel Capacity 272 gal
Armament:
Four guns ahead of the pilot’s cockpit were originally to be imported 23-mm Madsen cannons, but in February 1939, two .30-caliber and .50-caliber guns were specified, as then planned for the F4F-3. Four .50-caliber guns were scheduled in July 1940.
Bomb cells in wing, 20 5.2-pound anti-aircraft bombs in five containers within each wing;
they were to be released in salvos at a fixed distance above an enemy formation.