The Grumman Cats  [@ RAF Duxford]

In March 1936, the Grumman Aircraft Corporation was awarded a development contract to build an all-metal biplane fighter, the XF4F-l, for the US Navy.  However, the biplane configuration was quickly shelved in favour of a monoplane design, the XF4F-2.  This flew on 2 September 1937, powered by a lO5Ohp Pratt & Whitney R- 1830-66 Twin Wasp radial engine.  The US Navy decided to develop the aircraft still further by installing a supercharged XR-1830-76 engine in a much redesigned airframe, the revamped machine, designated XF4F-3, flying for the first time on 12 February 1939. 

The Grumman Cats  [@ RAF Duxford]

In August, the US Navy issued its first production contract for 53 Grumman F4F-3 Wildcats, as the fighter had been named.  The first production aircraft flew in February 1940, but deliveries were slow and by the end of 1940 only 22 Wildcats had been handed over to Navy fighter squadrons, these units embarking on the USS Ranger and USS Wasp respectively.  Meanwhile France [1939], which had one aircraft carrier in commission and two more under construction, had expressed an interest in acquiring 100 Wildcats.  As the Twin Wasp engine was in short supply, the French machines were to be powered by the 1200hp R-1820-G205A Cyclone.  The order was later reduced to 81, and flight testing of the first of these aircraft was still in progress when France was overrun, so the order was taken over by the British Purchasing Commission on behalf of the Royal Navy, in whose service the F4F-3 was named Martlet I.