Military


F4U Corsair

The Chance Vought F4U-4/AU-1 was in production longer than any other U.S. fighter of World War II, and it proved to be a rugged, reliable ground attack aircraft in Korea. The prototype of the F4U first flew in May 1940, and the last Corsair left the Vought plant in December 1952, destined for the French naval air arm. While the F4F and P-40 (along with the luckless P39) held the line in the Pacific, other, newer designs were leaving production lines, and none too soon. The two best newcomers were the Army's Lockheed P-38 Lightning and the Navy's Vought F4U Corsair. The P38 quickly captured the headlines and public interest with its unique twin-boomed, twin-engine layout. It soon developed into a long-range escort, and served in the Pacific as well as Europe.

The Corsair was originally intended to fly from aircraft carriers, but its high landing speed, long nose that obliterated the pilot's view forward during the landing approach, and its tendency to bounce, banished the big fighter from American flight decks for a while. The British, however, modified the aircraft, mainly by clipping its wings, and flew it from their small decks. Deprived of its new carrier fighter-having settled on the new Grumman F6F Hellcat as its main carrier fighter-the Navy offered the F4U to the Marines. They took the first squadrons to the Solomons, and after a few disappointing first missions, they made the gullwinged fighter their own, eventually even flying it from the small decks of Navy escort carriers in the later stages of the war.

Vought Corsairs have long been a part of US Naval Aviation. First came the series of biplanes, starting in 1926. Before they were totally phased out, the XFU-1 entered the scene in 1940. The inverted gull-wing Corsairs continued the tradition for a total of some 30 years when the last of the fighter-bomber Corsairs were retired. After a break, the A-7 Corsair II (the biplane's name was unofficial) picked up in 1965 and continued until 1992.

Significantly, the first biplane Corsairs (O2Us), the F4Us, and the A-7s have all played key roles in Navy and Marine Corps combat operations.

The story of the Corsair of WW II and Korean operations starts in 1938. The Navy was looking for a new carrier fighter with significant increases in performance over the Grumman F4F and the Brewster F2A, then in the development/test stage. In the design competition a Vought proposal -- designed around the new Pratt and Whitney 1,800-hp R-2800 Double Wasp engine -- was awarded an experimental prototype contract.

The most unusual feature of Vought's design was its inverted gull wing, which allowed a shorter, lighter landing gear. This provided adequate ground clearance for large-diameter propeller required to absorb the power of what was then the largest available for a fighter airplane.

First flown on May 29, 1940, the XF4U-1 had an armament of four guns, two synchronized to fire through the propeller disc, the other two outboard in the wings. It was the first single-engine fighter capable of over 400 mph.

As part of the US military buildup which preceded Pearl Harbor, production of the F4U-1 was ordered. Based on European wartime experience, increased armament and gunfire protection were required, resulting in extensive redesign of the production Corsairs. A large self-sealing fuel tank was located over the wing in the fuselage, while three .50 machine guns were installed outboard of the prop arc in each wing. The fuselage fuel tank caused the cockpit to be moved aft, which resulted in the characteristic "long nose" of the Corsair. An unusual feature of the Corsair was the fabric covering of the outer wing panels aft of the main spar. The construction was otherwise typically all metal with fabric-covered control surfaces.

Design and construction of the initial production F4U-1s were well along when the U.S. entered WW II. To meet anticipated Navy/Marine needs, Goodyear and Brewster were also given contracts to produce Corsairs as the FG-1 and F3A-1, respectively with Vought-Sikorsky retaining overall design responsibility.

June 1942 brought the first production F4U-1 flight, with testing, Navy trials and service introduction following. Early carrier trials revealed some problems with carrier landings, leading up to a decision to operate Corsairs from land until satisfactory characteristics were achieved. Thus, the Marines became a major user, along with shore-based Navy squadrons.

While this problem was being tackled, other improvements were made in the -1 Corsairs and incorporated at all three production plants. The most obvious was a raised, three-panel canopy for improved visibility. At the same time, a dozen F4U-1s were being modified as F4U-2 night fighters with a radar nacelle on the right wing, outboard. Additional conversions were subsequently made, and in early 1944, these night fighters were the first Corsairs based on U.S. carriers. The F4U-1C, with four 20mm cannon in the place of the six .50s; and the F4U and FG-1D, with additional store-carrying capability and water injection for the engine, followed. Brewster's Corsair production was cancelled before shifting to the -1D.

By the time the -1Ds were in service, the carrier landing problem had been solved. Changes to the main gear oleos and a taller tail wheel assembly led to full carrier use of the Corsair. A large number of -1 and -1D Corsairs were provided to the British Fleet Air Arm. Their wing tips were slightly clipped to clear the lower hangar overhead on the Royal Navy carriers, where they were fully operational even before the landing gear fixes were installed. Much of Goodyear's later production was built as the -1A, for land-based use without folding wings and other carrier systems. New Zealand's RNZAF also flew -1s. As a fighter and fighter-bomber, the Corsair was one of the outstanding WW II combat aircraft.

Attempts to increase the Corsair's performance at altitude led to the experimental turbo-supercharged XF4U-3. While a few FGs were modified late in the war to the FG-3 configuration, they did not become operational. The next improved engine installation was the "C" series Double Wasp, first in experimental -4s and subsequently in full production at Vought. Goodyear was in the process of changing over when production there was terminated after VJ day. The improved performance justified continued production after the war, including cannon-armed -4Bs, night fighter -4Ns, search radar-equipped -4Es, and photographic -4Ps. Goodyear's development of a much more powerful Corsair, the F2G with the Pratt and Whitney R-4360 engine, was also closed out in the postwar years after 10 production aircraft had been built.

The new E series R-2800 developed by Pratt and Whitney led to the -5 Corsair, with further performance improvements. Replacing the -4 in production in 1947, it was the first "all-metal" Corsair, including all-metal outer wing panels. The FG-1Ds continued as mainstays of the Reserves, while the -5s gradually replaced the -4s in fleet squadrons. The -5N night fighters became major components of carrier air groups as the new jets took over the basic fighter role. Some -5Ps were also built.

Production of the -5 series continued at Vought after its move to Dallas, and the Korean conflict brought the Corsair back once more into the forefront. F4U-4s returned in numbers to the carriers and winterized -5NL versions were built to operate better in frigid weather conditions. The Navy and Marines both very successfully employed the night fighter -5Ns and -5NLs. A low altitude, heavily armored version of the -5 was built as the XFU-6; production aircraft were redesignated AU-1s. Production of 110 completed the Navy acquisition of Corsairs, though the French F4U-7s were the last off the line. With the end of the Korean war in 1953, the Corsairs were rapidly released from operational squadrons, though they continued another few years in support roles.

Furnished to several other countries, particularly Central and South America, as well as France, Corsairs continued in operational use and in intermittent combat for many more years. They also made their debut in air races soon after WW II, especially with the R-4360 engine, and established a winning record. With their unique wing configuration and outstanding performance, the more than 12,500 built are well commemorated by the few that can still be regularly seen flying at air shows and air races, and those in many museums.



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