The Grumman F4F Wildcat was the US Navy's primary carrier-based fighter aircraft during the beginning of World War II, it was mainly used during the Pacific War against Japan. Even though inferior to its Japanese counterpart, the Mitsubishi A6M, in terms of speed, manoeuvrability and range, the F4F was able to achieve kill ratios of up to 6.9:1, the reason for its success was an aerial combat tactic called "Thach Weave", developed by John S. Tach, the basic way in which the Thach Weave works, is that if for example two aircraft are being chased by enemies, two other are waiting behind, to then attack those enemies focused on the two other fighters, from behind.
Design and development
Grumman fighter development began with the two-seat Grumman FF biplane. The FF was the first U.S. naval fighter with a retractable landing gear. The wheels retracted into the fuselage, leaving the tires visibly exposed, flush with the sides of the fuselage. Two single-seat biplane designs followed, the F2F and F3F, which established the general fuselage outlines of what would become the F4F Wildcat. In 1935, while the F3F was still undergoing flight testing, Grumman started work on its next biplane fighter, the G-16. At the time, the U.S. Navy favored a monoplane design, the Brewster F2A-1, ordering production early in 1936. However, an order was also placed for Grumman's G-16 (given the navy designation XF4F-1) as a backup in case the Brewster monoplane proved to be unsatisfactory.
It was clear to Grumman that the XF4F-1 would be inferior to the Brewster monoplane, so Grumman abandoned the XF4F-1, designing instead a new monoplane fighter, the XF4F-2. The XF4F-2 would retain the same, fuselage-mounted, hand-cranked main landing gear as the F3F, with its relatively narrow track. The unusual manually-retractable main landing gear design for all of Grumman's U.S. Navy fighters up to and through the F4F, as well as for the amphibious Grumman J2F utility biplane, was originally created in the 1920s by Leroy Grumman for Grover Loening.[N 1] Landing accidents caused by failure of the main gear to fully lock into place were distressingly common.
The overall performance of Grumman's new monoplane was felt to be inferior to that of the Brewster Buffalo. The XF4F-2 was marginally faster, but the Buffalo was more maneuverable. It was judged superior and was chosen for production. After losing out to Brewster, Grumman completely rebuilt the prototype as the XF4F-3 with new wings and tail and a supercharged version of the Pratt & Whitney R-1830 "Twin Wasp" radial engine. Testing of the new XF4F-3 led to an order for F4F-3 production models, the first of which was completed in February 1940. France also ordered the type, powered by a Wright R-1820 "Cyclone 9" radial engine, but France fell to the Axis powers before they could be delivered and the aircraft went instead to the British Royal Navy, who christened the new fighter the Martlet. The U.S. Navy officially adopted the aircraft type on 1 October 1941 as the Wildcat. The Royal Navy's and U.S. Navy's F4F-3s, armed with four .50 in (12.7 mm) Browning machine guns, joined active units in 1940.
On 16 December 1940, the XF4F-3 prototype, BuNo 0383, c/n 356, modified from XF4F-2, was lost under circumstances that suggested that the pilot may have been confused by the poor layout of fuel valves and flap controls and inadvertently turned the fuel valve to "off" immediately after takeoff rather than selecting flaps "up". This was the first fatality in the type.
Even before the Wildcat had been purchased by the U.S. Navy, the French Navy and the Royal Navy Fleet Air Arm (FAA) had ordered the Wildcat, with their own configurations, via the Anglo-French Purchasing Board. The F4F Wildcat (known in British service at first as the Martlet) was taken on by the FAA as an interim replacement for the Fairey Fulmar. The Fulmar was a two-seat fighter with good range but operated at a performance disadvantage against single-seater fighters. Navalised Supermarine Spitfires were not available because of the greater need of the Royal Air Force. In the European theater, the Wildcat scored its first combat victory on Christmas Day 1940, when a land-based Martlet destroyed a Junkers Ju 88 bomber over the Scapa Flow naval base. This was the first combat victory by a US-built fighter in British service in World War II. The type also pioneered combat operations from the smaller escort carriers.
Six Martlets went to sea aboard the converted former German merchant vessel HMS Audacity in September 1941 and shot down several Luftwaffe Fw 200 Condor bombers during highly effective convoy escort operations. These were the first of many Wildcats to engage in aerial combat at sea. The British received 300 Eastern Aircraft FM-1s as the Martlet V in 1942–43 and 340 FM-2s as the Wildcat VI. In total, nearly 1,200 Wildcats would serve with the FAA. By January 1944, the Martlet name was dropped and the type was identified as the Wildcat.[N 2] In March 1945, Wildcats shot down four Messerschmitt Bf 109s over Norway, the FAA's last victory with a Wildcat.
- I would still assess the Wildcat as the outstanding naval fighter of the early years of World War II ... I can vouch as a matter of personal experience, this Grumman fighter was one of the finest shipboard aeroplanes ever created.
— Eric M. "Winkle" Brown, British test pilot
The last air-raid of the war in Europe was carried out by Fleet Air Arm aircraft in Operation Judgement, Kilbotn on May 5, 1945. Twenty eight Wildcat VI aircraft from Naval Air Squadrons 846, 853 and 882, flying from escort carriers, took part in an attack on a U-boat depot near Harstad, Norway. Two ships and a U-boat were sunk with the loss of one Wildcat and one Avenger torpedo-bomber.
The Wildcat was generally outperformed by the Mitsubishi Zero, its major opponent in the early part of the Pacific Theater, but held its own partly because, with relatively heavy armor and self-sealing fuel tanks, the Grumman airframe could survive far more damage than its lightweight, unarmored Japanese rival. Many U.S. Navy fighter pilots also were saved by the Wildcat's ZB homing device, which allowed them to find their carriers in poor visibility, provided they could get within the 30 mi (48 km) range of the homing beacon.
In the hands of an expert pilot using tactical advantage, the Wildcat could prove to be a difficult foe even against the formidable Zero. After analyzing Fleet Air Tactical Unit Intelligence Bureau reports describing the new carrier fighter, USN Commander "Jimmy" Thach devised a defensive tactic that allowed Wildcat formations to act in a coordinated maneuver to counter a diving attack, called the "Thach Weave." Nevertheless, the most widely employed tactic during Guadalcanal defense was high-altitude ambush, where hit-and-run manoeuvres were executed using altitude advantage. This was possible due to early warning system composed of Coastwatchers and radar.
Four U.S. Marine Corps Wildcats played a prominent role in the defense of Wake Island in December 1941. USN and USMC aircraft formed the fleet's primary air defense during the Battles of Coral Sea and Midway, and land-based Wildcats played a major role during the Guadalcanal Campaign of 1942–43. It was not until 1943 that more advanced naval fighters capable of taking on the Zero on more even terms, the Grumman F6F Hellcat and Vought F4U Corsair, reached the South Pacific theater.
The Japanese ace Saburō Sakai described the Wildcat's capacity to absorb damage:
- I had full confidence in my ability to destroy the Grumman and decided to finish off the enemy fighter with only my 7.7 mm machine guns. I turned the 20 mm cannon switch to the "off" position, and closed in. For some strange reason, even after I had poured about five or six hundred rounds of ammunition directly into the Grumman, the airplane did not fall, but kept on flying. I thought this very odd—it had never happened before—and closed the distance between the two airplanes until I could almost reach out and touch the Grumman. To my surprise, the Grumman's rudder and tail were torn to shreds, looking like an old torn piece of rag. With his plane in such condition, no wonder the pilot was unable to continue fighting! A Zero which had taken that many bullets would have been a ball of fire by now.
— Saburo Sakai, Zero
Grumman's Wildcat production ceased in early 1943 to make way for the newer F6F Hellcat, but General Motors continued producing Wildcats for both U.S. Navy and Fleet Air Arm use. At first, GM produced the FM-1 (identical to the F4F-4, but with four guns). Production later switched to the improved FM-2 (based on Grumman's XF4F-8 prototype, informally known as the "Wilder Wildcat") optimized for small-carrier operations, with a more powerful engine, and a taller tail to cope with the increased torque.
From 1943 onward, Wildcats equipped with bomb racks were primarily assigned to escort carriers for use against submarines and attacking ground targets, though they would also continue to score kills against Japanese fighters, bombers and kamikaze aircraft. Larger fighters such as the Hellcat and the Corsair and dedicated dive bombers were needed aboard fleet carriers, and the Wildcat's slower landing speed made it more suitable for shorter flight decks.
In the Battle off Samar on 25 October 1944, escort carriers of Task Unit 77.4.3 ("Taffy 3") and their escort of destroyers and destroyer escorts found themselves as the sole force standing between vulnerable troop transport and supply ships engaged in landings on the Philippine island of Leyte and a powerful Japanese surface fleet of battleships and cruisers. In desperation, lightly armed Avengers and FM-2 Wildcats from Taffys 1, 2 and 3 resorted to tactics such as strafing ships, including the bridge of the Japanese battleship Yamato, while the destroyers and destroyer escorts charged the enemy. Confused by the fierce resistance, and having suffered significant damage, the Japanese fleet eventually withdrew from the battle.
U.S. Navy Wildcats participated in Operation Torch. USN escort carriers in the Atlantic used Wildcats until the end of the war.
In all, 7,860 Wildcats were built.[N 3] During the course of the war, Navy and Marine F4Fs and FMs flew 15,553 combat sorties (14,027 of these from aircraft carriers), destroying 1,327 enemy aircraft at a cost of 178 aerial losses, 24 to ground/shipboard fire, and 49 to operational causes (an overall kill-to-loss ratio of 6.9:1). True to their escort fighter role, Wildcats dropped only 154 tons of bombs during the war.