VF-42 (CV-4), Spring 1942. The Grumman F4F Wildcat was an American carrier-based fighter that began service with both the United States Navy and the Fleet Air Arm in 1940. Although first used in combat by the British in Europe, the Wildcat would become the primary carrier fighter for the first year and a half of the United States Navy's involvement in World War II in the Pacific Theater. The FM Wildcat, built by General Motors, remained in service throughout the remainder of the war on escort carriers, where larger and heavier fighters could not be used.