The Grumman F4F Wildcat, an American carrier-based fighter aircraft, was introduced in 1940 by the United States Navy and the British Royal Navy, initially referred to as the Martlet.
Initially deployed by the British in the North Atlantic, the Wildcat emerged as the sole formidable fighter for the United States Navy and Marine Corps in the Pacific Theatre during the early stages of World War II.
As aircraft became accessible, the underwhelming Brewster Buffalo was phased out in favour of the Wildcat.
The Wildcat, despite its top speed of 318 mph (512 km/h), was overshadowed by the swifter (331 mph (533 km/h)), more agile, and longer-reaching Mitsubishi A6M Zero.
The US Navy aviators, including the renowned John “Jimmy” Thach, who devised fighter tactics to counter the A6M Zero, expressed significant dissatisfaction with the Wildcat’s inferior performance against its adversary during the battles of the Coral Sea and Midway.
In 1942, the Wildcat boasted an asserted air combat kill-to-loss ratio of 5.9:1, which increased to 6.9:1 for the duration of the war.
The knowledge gained from the Wildcat aircraft was subsequently utilised in the development of the faster F6F Hellcat.
Despite the Wildcat’s advantages in terms of range and manoeuvrability at lower speeds, the Hellcat excelled due to its superior power and high-speed capabilities, allowing it to surpass the Zero.
Wildcat production persisted until the end of the war, with Wildcats being deployed on escort carriers, as the larger and heavier Hellcat was not suitable for such operations.
Variants
U.S. Navy Wildcats
F4F-1 / F4F-2
The initial Grumman F4F-1 model was originally conceived as a biplane, but it was soon discovered to be less effective compared to other aircraft models, prompting a redesign into a monoplane known as the F4F-2.
Despite this modification, the F4F-2 still lagged behind the Brewster F2A Buffalo, which secured the first orders from the U.S. Navy.
However, with the enhancement of the F4F-3 through the installation of a more potent Pratt & Whitney Twin Wasp R-1830-76 engine equipped with a two-stage supercharger, the aircraft finally demonstrated its full capabilities.
F4F-3
The U.S. Navy placed orders for the aircraft, and some were also ordered by France, equipped with Wright Cyclone engines.
After the fall of France, these aircraft were acquired by the Royal Navy’s Fleet Air Arm and were put into service on September 8, 1940.
Grumman designated these aircraft as G-36A, which featured a distinct cowling compared to earlier F4Fs and fixed wings.
They were originally intended to be equipped with French armament and avionics upon delivery.
In the British service, these aircraft were initially referred to as the Martlet I.
However, it should be noted that not all Martlets had identical specifications to the U.S. Navy aircraft.
F4F-3S Wildcatfish
The F4F-3S Wildcatfish, a floatplane variant of the F4F-3, was developed by Edo Aircraft Corporation by equipping one F4F-3 aircraft with twin floats.
This adaptation was specifically designed for operations at remote island bases in the Pacific region prior to the establishment of proper airfields.
The concept for the F4F-3S was influenced by the A6M2-N “Rufe,” a modified version of the Mitsubishi A6M2 “Zeke.”
The specific aircraft, BuNo 4038, underwent modifications to transform into the F4F-3S “Wildcatfish,” with Edo Aircraft Corporation producing the twin floats for this purpose.
To enhance stability, additional small auxiliary fins were incorporated into the tail plane, and later a ventral fin was added due to insufficient stability.
The maiden flight of the F4F-3S took place on February 28, 1943, with its maximum speed reduced to 241 mph (388 km/h) due to the added weight and drag of the floats.
Given that the original F4F-3’s performance was already inferior to that of the Zero, the F4F-3S was deemed to have limited practicality.
Nevertheless, the swift construction of airfields at forward bases by the “Seabees” minimized the necessity for such floatplane adaptations, resulting in only one F4F-3S being converted.
F4F-4
The F4F-4, which was introduced in 1941, featured the innovative Sto-Wing-design folding wings, a patented design by Grumman.
This new version was equipped with six machine guns, allowing for more efficient storage of aircraft on carriers.
However, American pilots were not as fond of the F4F-4 due to the fact that the same amount of ammunition was spread across two additional guns, resulting in decreased firing time.
The Royal Navy, on the other hand, welcomed the increase to six guns as it provided greater firepower against German and Italian adversaries.
Despite the advantages of extra guns and folding wings, the F4F-4 suffered from increased weight and reduced performance, with a top speed of approximately 318 mph at 19,400 ft.
The rate of climb was also notably inferior in the F4F-4, with pilots experiencing ascent rates of only 500 to 1,000 ft per minute in combat conditions.
The folding wing design of the F4F-4 was intended to allow for the storage of five aircraft in the space typically required for two F4F-3s, resulting in a 50% increase in the number of Wildcats carried on U.S. fleet carriers.
Additionally, a variant of the F4F-4, known as the F4F-4B, was provided to the British with modifications such as a different cowling and a Wright Cyclone engine, receiving the designation of Martlet IV.
F4F-5 Wildcat
The XF4F-5 designation was assigned to two F4F-3 aircraft, specifically the third and fourth production planes with the Bureau Number (BuNo) 1846 and 1847.
These aircraft were equipped with a Wright R-1820-40 engine.
FM-1/-2 Wildcat
During World War II, General Motors and Eastern Aircraft collaborated to manufacture a total of 5,280 FM variants of the Wildcat aircraft.
While Grumman’s production of the Wildcat came to a halt in early 1943 to make room for the newer F6F Hellcat, General Motors continued to produce Wildcats for both the U.S. Navy and Fleet Air Arm.
As the war progressed, the Wildcat gradually became outdated as a frontline fighter when compared to the faster F6F Hellcat, which boasted a top speed of 380 mph (610 km/h), or the even swifter F4U Corsair, which could reach speeds of up to 446 mph (718 km/h).
However, the Wildcat still proved to be sufficient for operations on small escort carriers, particularly in countering submarine and shore threats.
These relatively modest escort carriers primarily carried two types of aircraft: the Wildcats and the TBM Avengers, which were built by General Motors.
The Wildcat’s advantage lay in its lower landing speed and its ability to take off without the need for a catapult, making it better suited for shorter flight decks.
Initially, General Motors produced the FM-1 variant, which closely resembled the F4F-4 model.
However, they made some modifications by reducing the number of guns to four and incorporating wing racks capable of carrying two 250-lb (110 kg) bombs or six rockets.
Subsequently, production shifted to the improved FM-2 variant, which was based on Grumman’s XF4F-8 prototype.
This version was specifically optimized for operations on small carriers and featured a more powerful engine, the 1,350 hp (1,010 kW) Wright R-1820-56, as well as a taller tail to handle the torque generated by the engine.
F4F-7
The F4F-7, a modified version primarily used for photoreconnaissance purposes, underwent certain alterations including the removal of its armour and armament.
Notably, it featured non-folding “wet” wings capable of accommodating an extra 555 gallons (2,101 liters) of fuel, thereby increasing its overall capacity to approximately 700 gallons (2,650 litres).
This enhancement significantly extended its range to an impressive 3,700 miles (5,955 kilometres).
In total, a modest quantity of 21 F4F-7 aircraft were manufactured.
Royal Navy Martlets
Martlet Mk I
In late 1939, Grumman was awarded a contract by the French government to manufacture 81 units of the G-36A aircraft model, specifically designed for their newly commissioned Joffre-class aircraft carriers, Joffre and Painlevé.
The primary deviation from the standard G-36 model was necessitated by the unavailability of the two-stage supercharged engine found in the F4F-3 variant, which was not permitted for export.
To compensate for this limitation, the G-36A was equipped with a nine-cylinder, single-row Wright R-1820-G205A radial engine, boasting a power output of 1,200 horsepower (890 kW) and featuring a single-stage, two-speed supercharger.
Additionally, the G-36A incorporated French instruments calibrated in the metric system, a radio system, and a gun sight.
One notable modification made to the G-36A was the adaptation of the throttle to align with the pre-war French operational practices.
In this regard, the throttle lever was repositioned towards the pilot, or moved backwards, to increase engine power.
This adjustment ensured compatibility with the French pilots’ accustomed control configuration.
The French armament plan involved the installation of six 7.5 mm (.296 in) Darne machine guns, with two placed in the fuselage and four in the wings.
On May 11, 1940, the inaugural flight of the first G-36A took place.
Following France’s defeat in the Battle of France, all contracts were transferred to Britain.
Subsequently, modifications were made to the throttle, and four 0.50-inch (12.7-mm) guns were incorporated into the wings, while efforts were made to erase any remnants of the original ownership.
Blackburn, the company responsible for the Martlets, undertook the necessary alterations for British usage, a practice that continued for subsequent models.
British gunsights, catapult spools, and other equipment were also installed.
Despite initial attempts to fit British radio sets, it was ultimately decided to utilize the superior American equipment.
The first Martlets were introduced into British service in August 1940, specifically assigned to the 804 Naval Air Squadron stationed at Hatston in the Orkney Islands.
The Martlet Mk I, lacking a wing folding mechanism, was primarily utilized from land bases.
However, there were six aircraft of 882 Sqn aboard Illustrious from March 1942, which served as a notable exception.
In April 1942, while in port at Freetown, Illustrious transferred two Martlet I aircraft to HMS Archer.
During the journey to Durban, one of the four retained Martlet I aircraft on Illustrious had its wings fitted with a folding mechanism by the ship’s staff.
Additionally, in 1940, Belgium placed an order for a minimum of 10 Martlet Mk 1s.
These aircraft were intended to undergo modifications that involved removing the tail hook.
Unfortunately, Belgium surrendered before any of the aircraft could be delivered.
Consequently, on May 10, 1940, the aircraft order was transferred to the Royal Navy.
Martlet Mk II
Prior to the Fleet Air Arm assuming control of the Martlet Mk Is, an order for 100 G-36B fighters had already been placed.
The British opted for the Pratt & Whitney R-1830-S3C4-G engine to provide power for this aircraft, which featured a single-stage, two-speed supercharger.
In order to ensure compatibility with the first 3 Illustrious class carriers, which had narrow elevators unsuitable for non-folding wing aircraft, the FAA agreed to a delay in delivery to have the Martlets equipped with the Grumman-designed and patented Sto-Wing folding wing system, originally utilised on U.S. Navy F4F-4 Wildcats.
Martlet Mk III
The initial batch of 30 F4F-3As was made available for purchase by Greece following the Italian incursion in November 1940.
Nevertheless, by the time Greece succumbed to defeat in April 1941, the airplanes had only made it as far as Gibraltar.
Subsequently, the Fleet Air Arm (FAA) assumed control of these aircraft, designating them as Martlet Mk III (B).
Due to the absence of folding wings on these planes, they were exclusively deployed from terrestrial airfields.
Martlet Mk IV
The British requirements led to the acquisition of 220 F4F-4s by the Royal Navy.
Notably, these aircraft were modified with a Wright R-1820-40B Cyclone engine, which was housed in a sleeker and more streamlined cowling.
The cowling featured a unique design with a single double-wide flap on either side of the rear, and it lacked a lip intake.
Martlet Mk V
The Fleet Air Arm procured a total of 312 FM-1s, initially designated as Martlet V.
However, in January 1944, it was decided to preserve the original American names for the aircraft supplied by the United States.
Consequently, the batch was reclassified as the Wildcat V.
Wildcat Mk VI
The Air Ministry designated the FM-2 Wildcat in FAA service as the Wildcat VI.
Specifications
Crew
1
Length
28 ft 9 in (8.76 m)
Wingspan
38 ft 0 in (11.58 m)
Height
11 ft 10 in (3.61 m)
Wing area
260 sq ft (24 m2)
Airfoil
Root
NACA 23015
Tip
NACA 23009
Empty weight
4,907 lb (2,226 kg)
Gross weight
7,423 lb (3,367 kg)
Powerplant
1 × Pratt & Whitney R-1830-76,
14-cylinder air-cooled radial piston engine,
1,200 hp (890 kW)
Propellers
3-bladed constant-speed propeller
Performance
Maximum speed
331 mph (533 km/h, 288 kn)
Range
845 mi (1,360 km, 734 nmi)
Service ceiling
39,500 ft (12,000 m)
Rate of climb
2,303 ft/min (11.70 m/s)
Wing loading
28.5 lb/sq ft (139 kg/m2)
Power/mass
0.282 kW/kg (0.172 hp/lb)
Armament
Guns
4 × 0.50 in (12.7 mm) AN/M2 Browning machine guns with 450 rounds per gun
Bombs
2 × 100 lb (45.4 kg) bombs and/or 2 × 58 US gal (48 imp gal; 220 l) drop tanks.
