The Grumman F6F Hellcat is an American carrier-based fighter aircraft of World War II.
Designed to replace the earlier F4F Wildcat and to counter the Japanese Mitsubishi A6M Zero, it was the United States Navy’s dominant fighter in the second half of the Pacific War.
In gaining that role, it prevailed over its faster competitor, the Vought F4U Corsair, which initially had problems with visibility and carrier landings.
Powered by a 2,000 hp (1,500 kW) Pratt & Whitney R-2800 Double Wasp, the same powerplant used for both the Corsair and the United States Army Air Forces (USAAF) Republic P-47 Thunderbolt fighters, the F6F was an entirely new design, but it still resembled the Wildcat in many ways.
Some military observers tagged the Hellcat as the “Wildcat’s big brother”.
The F6F made its combat debut in September 1943 and was best known for its role as a rugged, well-designed carrier fighter, which was able to outperform the A6M Zero and help secure air superiority over the Pacific theatre.
In total, 12,275 were built in just over two years.
Hellcats were credited with destroying a total of 5,223 enemy aircraft while in service with the U.S. Navy, U.S. Marine Corps, and Royal Navy Fleet Air Arm (FAA).
This was more than any other Allied naval aircraft.
After the war, Hellcats were phased out of frontline service in the US, but radar-equipped F6F-5Ns remained in service as late as 1954 as night fighters.
Grumman had been working on a successor to the F4F Wildcat since 1938, and the contract for the prototype XF6F-1 was signed on 30 June 1941.
The aircraft was originally designed to use the Wright R-2600 Twin Cyclone two-row, 14-cylinder radial engine of 1,700 hp (1,300 kW), driving a three-bladed Curtiss Electric propeller.
Instead of the Wildcat’s narrow-track, hand-cranked, main landing gear retracting into the fuselage inherited from the F3F, the Hellcat had wide-set, hydraulically actuated landing-gear struts that rotated through 90° while retracting backwards into the wings, but with full wheel doors fitted to the struts that covered the entire strut and the upper half of the main wheel when retracted and twisted with the main gear struts through 90° during retraction.
The wing was mounted lower on the fuselage and was able to be hydraulically or manually folded, with each panel outboard of the undercarriage bay folding backwards from pivoting on a specially oriented, Grumman-patented “Sto-Wing” diagonal axis pivoting system much like the earlier F4F, with a folded stowage position parallel to the fuselage with the leading edges pointing diagonally down.
Throughout early 1942, Leroy Grumman, along with his chief designers Jake Swirbul and Bill Schwendler, worked closely with the U.S. Navy’s Bureau of Aeronautics (BuAer) and experienced F4F pilots, to develop the new fighter in such a way that it could counter the Zero’s strengths and help gain air dominance in the Pacific Theatre of Operations.
On 22 April 1942, Lieutenant Commander Butch O’Hare toured the Grumman Aircraft company and spoke with Grumman engineers, analysing the performance of the F4F Wildcat against the Mitsubishi A6M Zero in aerial combat.
BuAer’s Lt Cdr A. M. Jackson directed Grumman’s designers to mount the cockpit higher in the fuselage.
In addition, the forward fuselage sloped down slightly to the engine cowling, giving the Hellcat’s pilot good visibility.
Based on combat accounts of encounters between the F4F Wildcat and A6M Zero, on 26 April 1942, BuAer directed Grumman to install the more-powerful, 18-cylinder Pratt & Whitney R-2800 Double Wasp radial engine which was already in use with Chance Vought’s Corsair since 1940 – in the second XF6F-1 prototype.
Grumman complied by redesigning and strengthening the F6F airframe to incorporate the 2,000 hp (1,500 kW) R-2800-10, driving a three-bladed Hamilton Standard propeller.
With this combination, Grumman estimated the XF6F-3s performance would increase by 25% over that of the XF6F-1.
The Cyclone-powered XF6F-1 (02981) first flew on 26 June 1942, followed by the first Double Wasp-equipped aircraft, the XF6F-3′ (02982), which first flew on 30 July 1942.
The first production F6F-3, powered by an R-2800-10, flew on 3 October 1942, with the type reaching operational readiness with VF-9 on USS Essex in February 1943.
Variants
XF6F prototypes
XF6F-1
First prototype, powered by a two-stage 1,600 hp (1,193 kW) Wright R-2600-10 Cyclone 14 radial piston engine.
XF6F-2
The first XF6F-1 prototype revised and fitted with a turbocharged Wright R-2600-16 Cyclone radial piston engine. R-2600 replaced by turbocharged R-2800-21.
XF6F-3
Second prototype fitted with a two-stage supercharged 2,000 hp (1,491 kW) Pratt & Whitney R-2800-10 Double Wasp radial piston engine.
XF6F-4
One F6F-3 fitted with a two-speed turbocharged 2,100 hp (1,566 kW) Pratt & Whitney R-2800-27 Double Wasp radial piston engine.
XF6F-6
Two F6F-5s that were fitted with the 2,100 hp (1,566 kW) Pratt & Whitney R-2800-18W radial piston engine, and four-bladed propellers.
Series production
F6F-3
(British designation Gannet F. Mk. I, and then later, renamed Hellcat F. Mk. I, January 1944)
Single-seat fighter, fighter-bomber aircraft, powered by a 2,000 hp (1,491 kW) Pratt & Whitney R-2800-10 Double Wasp radial piston engine.
F6F-3E
Night fighter version, equipped with an AN/APS-4 radar in a fairing on the starboard outer wing.
F6F-3N
Another night fighter version, equipped with a newer AN/APS-6 radar in a fairing on the starboard outer wing.
F6F-5 Hellcat (British Hellcat F. Mk. II)
Improved version, with a redesigned engine cowling, a new windscreen structure with an integral bulletproof windscreen, new ailerons and strengthened tail surfaces; powered by a 2,200 hp (1,641 kW) Pratt & Whitney R-2800-10W (-W denotes Water Injection) radial piston engine.
F6F-5K Hellcat
A number of F6F-5s and F6F-5Ns were converted into radio-controlled target drones.
F6F-5N Hellcat (British Hellcat N.F. Mk II)
Night fighter version, fitted with an AN/APS-6 radar.
Some were armed with two 20 mm (0.79 in) AN/M2 cannon in the inner wing bays and four 0.50 in (12.7 mm) M2 Browning machine guns in the outer.
F6F-5P Hellcat
Small numbers of F6F-5s were converted into photo-reconnaissance aircraft, with the camera equipment being fitted in the rear fuselage.
Hellcat FR. Mk. II
This designation was given to British Hellcats fitted with camera equipment.
FV-1
Proposed designation for Hellcats to be built by Canadian Vickers; cancelled before any built.
Specifications
Crew
1
Length
33 ft 7 in (10.24 m)
Wingspan
42 ft 10 in (13.06 m)
Height
13 ft 1 in (3.99 m)
Wing area
334 sq ft (31.0 m2)
Aspect ratio
5.5
Airfoil
Root
NACA 23015.6
Tip
NACA 23009
Empty weight
9,238 lb (4,190 kg)
Gross weight
12,598 lb (5,714 kg)
Max take-off weight
15,415 lb (6,992 kg)
Fuel capacity
250 US gal (208 imp gal; 946 l) internal.
Up to 3 × 150 US gal (125 imp gal; 568 l) external drop tanks
Zero-lift drag coefficient
0.0211
Drag area
7.05 sq ft (0.655 m2)
Powerplant
1 × Pratt & Whitney R-2800-10W Double Wasp,
18-cylinder air-cooled radial piston engine,
2,200 hp (1,600 kW) with a two-speed two-stage supercharger and water injection
Propellers
3-bladed Hamilton Standard, 13 ft 1 in (3.99 m) diameter constant-speed propeller
Performance
Maximum speed
391 mph (629 km/h, 340 kn)
Stall speed
84 mph (135 km/h, 73 kn)
Combat range
945 mi (1,521 km, 821 nmi)
Ferry range
1,530 mi (2,460 km, 1,330 nmi)
Service ceiling
37,300 ft (11,400 m)
Rate of climb
2,600 ft/min (13 m/s)
Time to altitude
20,000 ft (6,096 m) in 7 minutes 42 seconds
Lift-to-drag
12.2
Wing loading
37.7 lb/sq ft (184 kg/m2)
Power/mass
0.16 hp/lb (0.26 kW/kg)
Take-off runs
799 ft (244 m)
Armament
Guns
6× 0.50 in (12.7 mm) M2 Browning machine guns, with 400 rounds per gun,
(All F6F-3, and most F6F-5)
Or
2 × 0.79 in (20 mm) AN/M2 cannon, with 225 rounds per gun
&
4 × 0.50 in (12.7 mm) Browning machine guns with 400 rounds per gun
Rockets
6 × 5 in (127 mm) HVARs
Or
2 × 11+3⁄4 in (298 mm) Tiny Tim unguided rockets
Bombs
Up to 4,000 lb (1,800 kg) full load, including:
Bombs or Torpedoes
(Fuselage mounted on centreline rack)
1 × 2,000 lb (910 kg) bomb
Or
1 × Mk.13-3 torpedo
Underwing bombs
(F6F-5 had two additional weapons racks either side of fuselage on wing centre-section)
