Vought F4U Corsair - Variants

Variants

During World War II, Corsair production expanded beyond Vought to include Brewster and Goodyear models. Allied forces flying the aircraft in World War II included FAA and RNZAF. Eventually, more than 12,500 F4Us would be built, comprising 16 separate variants.

F4U-1 (Corsair Mk I Fleet Air Arm): The first production version of the Corsair with the original cockpit seat height and "bird cage" canopy. The differences over the XF4U-1 were as follows:

• Six .50 in (12.7 mm) Browning AN/M2 machine guns were fitted in the outer wing panels, displacing fuel tanks.
• An enlarged 237 gal (897 l) fuel tank was fitted ahead of the cockpit, in place of the fuselage armament. The cockpit was moved back by 32 in (810 mm).
• The fuselage was lengthened by 1 ft 5 in (0.43 m).
• The more powerful R-2800-8 Double Wasp was fitted.
• 150 pounds (68 kg) of armor plate was fitted to the cockpit and a 1.5 in (38 mm) bullet-resistant glass screen was fitted behind the curved windscreen.
• IFF transponder equipment was fitted.
• Curved transparent panels were incorporated into the fuselage behind the pilot's headrest.
• The flaps were changed from deflector type to NACA slotted.
• The span of the ailerons was increased while that of the flaps was decreased.
• One 62 gal (234 l) auxiliary fuel cell (not a self-sealing type) was installed in each wing leading edge, just outboard of the guns.

A land-based version for the USMC, without the folding wing capability, was built by Goodyear under the designation FG-1. In Fleet Air Arm service the F4U-1 was given the service name Corsair Mk I. Vought also built a single F4U-1 two-seat trainer; the Navy showed no interest.

F4U-1A (Corsair Mk II): The designation F4U-1A does not appear in lists of Corsair Bureau Numbers and was not in official use, being applied post-war to differentiate mid-to-late production F4U-1s from the early production variant. Mid-to-late production Corsairs incorporated a new, taller and wider clear-view canopy with only two frames, along with a simplified clear view windscreen. The cockpit seat was raised 7 in (180 mm) which, with the wider canopy top section, allowed the pilot better visibility over the long nose. The Plexiglas rear-view windows as well as the one under the cockpit were omitted. The tailwheel strut was lengthened, which also aided the pilot's forward view. These Corsairs were the first "carrier capable" variant and introduced a 6 in (150 mm)-long stall strip just outboard of the gun ports on the starboard wing leading edge and improved undercarriage oleo struts which eliminated bouncing on landing. F4U-1s supplied to the USMC lacked arrester hooks and had a pneumatic tail wheel, instead of the smaller diameter solid rubber type used for carrier operations. Additionally, an experimental R-2800-8W engine with water injection was fitted on one of the late F4U-1As. After satisfactory results, many F4U-1As were fitted with the new powerplant. The aircraft carried 237 gal (897 l) in the main fuel tank, located in front of the cockpit, as well as an unarmored, non-self-sealing 62 gal (235 l) fuel tank in each wing. This version of the Corsair was the first to be able to carry a drop tank under the center-section. With drop tanks fitted, the fighter had a maximum ferry range of just over 1,500 mi (2,400 km).

A land-based version, without the folding wing capability, was built by Goodyear as the FG-1A. In British service, the aircraft type was modified with "clipped" wings (8 in (200 mm) was cut off each wingtip) for use on British aircraft carriers, under the designation Corsair Mk II.

F3A-1 (Corsair Mk. III): This was the designation for the Brewster-built F4U-1. Just over 700 were built before Brewster was forced out of business. Poor production techniques and shabby quality control meant that these aircraft were red-lined for speed and prohibited from aerobatics after several lost their wings. This was later traced to poor quality wing fittings. None of the Brewster-built Corsairs reached front line units.

F4U-1B: This was an unofficial post-war designation used to identify F4U-1s modified for FAA use.

F4U-1C: The prototype F4U-1C, BuNo50277, appeared in August 1943 and was based on an F4U-1. A total of 200 of this variant were built July–November 1944; all were based on the F4U-1D and were built in parallel with that variant. Intended for ground-attack as well as fighter missions, the F4U-1C was similar to the F4U-1D but its six machine guns were replaced by four 20 millimetre (0.79 in) AN/M2 cannons with 231 rounds of ammunition per gun. The F4U-1C was introduced to combat during 1945, most notably in the Okinawa campaign. Aviators preferred the standard armament of six .50 in (12.7 mm) machine guns since they were already more than powerful enough to destroy most Japanese aircraft, and had more ammunition and a higher rate of fire. The weight of the Hispano cannon and their ammunition affected the flight performance, especially its agility, but the aircraft was found to be especially potent in the ground attack role.

F4U-1D (Corsair Mk IV): Built in parallel with the F4U-1C, but was introduced in April 1944. It had the new -8W water-injection engine. This change gave the aircraft up to 250 hp (190 kW) more power, which, in turn, increased performance. Speed was increased from 417 mph (671 km/h) to 425 mph (684 km/h). Due to the U.S. Navy's need for fighter-bombers, it had a payload of rockets double the -1A's, as well as twin-rack plumbing for an additional belly drop tank. However, these modifications necessitated the need for rocket tabs (attached to fully metal-plated underwing surfaces) and bomb pylons to be bolted on the fighter, causing extra drag. Additionally, the role of fighter-bombing was a new task for the Corsair and the wing fuel cells proved too vulnerable and were removed. The extra fuel carried by the two drop tanks would still allow the aircraft to fly relatively long missions despite the heavy, un-aerodynamic load. The regular armament of six machine guns were implemented as well. The canopies of most -1Ds had their struts removed along with their metal caps, which were used — at one point — as a measure to prevent the canopies' glass from cracking as they moved along the fuselage spines of the fighters. Also, the clear-view style "Malcolm Hood" canopy used initially on Supermarine Spitfire and P-51C Mustang aircraft was adopted as standard equipment for the -1D model, and all later F4U production aircraft. Additional production was carried out by Goodyear (FG-1D) and Brewster (F3A-1D). In Fleet Air Arm service, the latter was known as the Corsair III, and both had their wingtips clipped - 8 inches (203 mm) per wing - to allow storage in the lower hangars of British carriers.

F4U-1P: A rare photo reconnaissance variant.

XF4U-2: Special night fighter variant, equipped with two auxiliary fuel tanks.

F4U-2: Experimental conversion of the F4U-1 Corsair into a carrier-borne night fighter, armed with five .50 in (12.7 mm) machine guns (the outboard, starboard gun was deleted), and fitted with Airborne Intercept (AI) radar set in a radome placed outboard on the starboard wing. Since Vought was preoccupied with more important projects, only 32 were converted from existing F4U-1s by the Naval Aircraft Factory and another two by front line units. The type saw combat with VF(N)-101 aboard USS Enterprise and USS Intrepid in early 1944, VF(N)-75 in the Solomon Islands and VMF(N)-532 on Tarawa.

XF4U-3: Experimental aircraft built to hold different engines in order to test the Corsair's performance with a variety of power plants. This variant never entered service. Goodyear also contributed a number of airframes, designated FG-3, to the project. A single sub-variant XF4U-3B with minor modifications was also produced. XF4U-3B, planned procurement for the FAA.

XF4U-4: New engine and cowling.

F4U-4: The last variant to see action during World War II, deliveries to the U.S. Navy of the F4U-4 began late in 1944. It fully equipped naval squadrons four months before the end of hostilities. It had the 2,100 hp (1,600 kW) dual-stage-supercharged -18W engine. When the cylinders were injected with the water/alcohol mixture, power was boosted to 2,450 hp (1,830 kW). The aircraft required an air scoop under the nose and the unarmored wing fuel tanks of 62 gal (234 l) capacities were removed for better maneuverability at the expense of maximum range. The propeller was changed to a four blade type. Maximum speed was increased to 448 miles per hour (721 km/h) and climb rate to over 3,800 ft/min (1,180 m/min) as opposed to the 2,900 ft/min (884 m/min) of the F4U-1A. The service ceiling also increased significantly from 37,000 feet (11,000 m) to 41,000 feet (12,000 m). The "4-Hog" retained the original armament and had all the external load (i.e., drop tanks, bombs) capabilities of the F4U-1D. The windscreen was now flat bullet-resistant glass to avoid optical distortion, a change from the curved Plexiglas windscreens with the internal plate glass of the earlier Corsairs. Vought also tested the two F4U-4Xs (BuNos 49763 and 50301, prototypes for the new R2800) with fixed tiptanks (the Navy showed no interest) and an Aeroproducts six-blade contraprop (not accepted for production).

F4U-4B: Designation for F4U-4s to be delivered to the British Fleet Air Arm, but were retained by the U.S. for its own use. The Fleet Air Arm received no F4U-4s.

F4U-4C: 300 F4U-4s ordered with alternate gun armament of four 20 millimetres (0.79 in) AN/M2 cannon.

F4U-4E and F4U-4N: Developed late in WWII, these night fighters featured radar radomes projecting from the starboard wingtip. The -4E was fitted with the APS-4 search radar, while the -4N was fitted with the APS-6 type. In addition, these aircraft were often refitted with four 20mm M2 cannons similar to the F4U-1C. Though these variants would not see combat during WWII, the night fighter variants would see great use during the Korean war.

F4U-4K: Experimental drone.

F4U-4P: As with the -1P, a rare photo reconnaissance variant.

XF4U-5: New engine cowling, other extensive changes.

F4U-5: A 1945 design modification of the F4U-4, first flown on 21 December 1945, was intended to increase the F4U-4 Corsair's overall performance and incorporate many Corsair pilots' suggestions. It featured a more powerful Pratt and Whitney R-2800-32(E) engine with a two stage supercharger, rated at a maximum of 2,850 hp (2,130 kW). Other improvements included automatic blower controls, cowl flaps, intercooler doors and oil cooler for the engine, spring tabs for the elevators and rudder, a completely modernized cockpit, a completely retractable tail wheel, and heated cannon bays and pitot head. The cowling was lowered two degrees to help with forward visibility, but perhaps most striking as the first variant to feature all-metal wings (223 units produced).

F4U-5N: Radar equipped version (214 units produced)

F4U-5NL: Winterized version (72 units produced, 29 modified from F4U-5Ns (101 total). Fitted with rubber de-icing boots on the leading edge of the wings and tail.

F4U-5P: Long-range photo-reconnaissance version (30 units produced)

F4U-6: Redesignated AU-1, this was a ground-attack version produced for the U.S. Marine Corps.

F4U-7 : AU-1 developed for the French Navy.

FG-1E: Goodyear FG-1 with radar equipment.

FG-1K: Goodyear FG-1 as drone.

FG-3: Turbosupercharger version converted from FG-1D.

FG-4:Goodyear F4U-4, never delivered.

AU:U.S. Marines attack variant re-designated from F4U-6