With its distinctive gull-wing, the Corsair was in production so long that it became the last American propeller-driven fighter to roll out of the factory. It was the most successful of three new fighter projects launched in 1938 to bring carrier-based performance up to the level of land-based contemporaries. The Navy evaluated proposals from five companies in April 1938 that offered increased power and weaponry, including anti-aircraft bombs.
The Grumman XF5F-1 and Vought XF4U-1 were ordered June 30, 1938, and the Bell XFL-1 was ordered November 8. The first twin-engine single-seater built for the Navy, the XF5F-1 was first flown on April 1, 1940, by B. A. Gillies with Wright Cyclones slung ahead and below the leading edge of stubby square-cut wings. Rotating in opposite directions, the R-1820-40 and -42 engines could be close together since the short fuselage began behind the wing’s leading edge and extended back to twin rudders. Main wheels folded back into the engine nacelles, while the tail wheel was fixed and the wings folded upwards for carrier stowage.
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. The most unusual armament planned for all three new types was 20 5.2-pound anti-aircraft bombs in five containers outboard within each wing; they were to be released in salvos at a fixed distance above an enemy formation.
Delayed by cooling troubles, the prototype did not complete tests until February 1941, and was returned to the factory for rework with an extended nose and engine nacelles, wing fillets, and prop spinners added to reduce drag. By that time the XF5F-1 returned to Anacostia on July 24, 1941, the Navy’s interest had shifted to the XF7F-1, and like the XP-50 Army version, the project ended without production.
First flown May 13, 1940, the Bell XFL-1 was a carrier version of the XP-39 Airacobra, with an 1,150-hp Allison XV-1710-6 placed behind the pilot and turning the propeller by a drive shaft extended to the nose. Instead of tricycle wheels, the Navy insisted on conventional tail-down landing gear, with an arrestor hook added for carrier landings. Radiators below the wing cooled the only inline engine on a post-1927 Navy fighter.
Known as the Bell Model 5 Airabonita by the company, it had provisions for a 37-mm cannon and two .30-caliber guns in the nose with a telescopic sight, and wing cells for 20 anti-aircraft bombs aimed through a small window beneath the cockpit. However, the cannon was unavailable and would be replaced by a .50-caliber gun, although no weapons were ever tested on the XFL-1. Delivered from Buffalo to Anacostia on February 27, 1941, the XFL-1 never was a successful fighter, even if its performance had not been surpassed by the Vought XF4U-1.
Designed by Rex Beisel, who had designed the Navy’s little TS biplane in 1922, the Vought Corsair was first Navy plane built around the Pratt & Whitney 1,850-hp XR-2800-4 Double Wasp. In order to give the 13-foot,4-inch diameter three-bladed propeller sufficient ground clearance without making the landing gear too stilted and heavy, the wing was gulled downward, a technique that also promised reduced drag at the juncture of wingand body. The wheels retracted backward and swiveled 90 degrees flat into the wing, which folded upward for stowage.
Finished with a smooth spot-welded skin, the XF4U-1 was first flown on May 29, 1940, at Stratford by Lyman A. Bullard. Two .30-caliber guns were mounted above the engine with 500 rpg, and two .50-caliber wing guns were provided with 200 rpg. Like the XF5F-l and XFL-1, the XF4U-1 had wing cells for anti-aircraft bombs; up to forty 5-pound bombs might be dropped on bomber formations from above. A window for aiming was provided in the Vought’s cockpit bottom, but these bombs were not included on any production aircraft.
The contract specification called for 390 mph at 24,000 feet, but the company claimed that this was the first American fighter to surpass 400 mph. The Army Air Corps chief was told that the XF4U-1 had shown a speed of 397 mph, by Army officers who had inspected it on October 29. On November 28, 1940, the Navy requested Vought to propose a production configuration with increased firepower, fuel capacity, and internal protection.
An initial production contract for 584 F4U-ls was placed June 30, 1941, but expanded requirements began the VGB program in November to pool the resources of Vought, Goodyear, and Brewster to produce Corsair fighters. On June 25, 1942, the first production F4U-1 was flown by Boone T. Guyton with a 2,000-hp R-2800-8 and longer fuselage. To make room for a 237-gallon self-sealing fuel tank, the cockpit was moved back and provided with 150 pounds of armor.
Like most American World War II fighters, the F4U-1 had six .50-caliber M-2 guns in the wings, with 2,350 rounds of ammunition. Instead of the bomb cells in the wings, there were a pair of unprotected 62-gallon fuel tanks, and the usual racks for two 116-pound bombs could be added.
By the end of 1942, 178 F4U-1s had been accepted and the first squadron to begin receiving them, on October 26, 1942, was VMF-124 of the Marines at San Diego. VFM-124 arrived on Guadacanal on February 12, 1943, with 24 Corsairs nearly 80-mph faster than the F4F-4s previously used.
The second Corsair squadron was the Navy’s VF-12 with 22 F4U-1s by January 1943, but efforts to qualify for aircraft carrier operations were frustrated by poor landing behavior, worsened by bad downward visibility and a severe bounce. VF-12 lost 14 pilots while training and changed to Grumman Hellcats in April 1943. Another Navy squadron, VF-17 at Norfolk, continued to try to perfect F4U-1 operations from a carrier.
But the Corsair was satisfactory for land-based operations and Marines established a definite superiority over enemy fighters. By July 2, 1943, all eight Marine fighter squadrons in the South Pacific used Corsairs.
Goodyear’s first FG-l flew at Akron on February 25, 1943, and the first Brewster’s F3A-1 Corsair flew at Johnsville on April 26; they were identical to the F4U-1. Beginning in May 1943, the Royal Navy got 95 F4U-1s as the Corsair I, training Fleet Air Arm (FAA) squadrons at Quonset Point.
A night fighter version had been proposed as early as November 8, 1941, and the first production F4U-1 was converted to an F4U-2 with an Aircraft Intercept (AI) radome on the starboard wingtip, an outboard gun deleted, and flown for tests to Quonset by January 7, 1943. The Naval Aircraft Factory converted 32 F4U-ls to the F4U-2 configuration by September and the first were issued to VF(N)-75 which made the first kill by a radar-equipped Navy fighter on the night of October 31, 1943.