The Grumman's fighters represent the strength of the US Navy Air Force during World War 2. The first of the family to prove itself in combat was F4F Wildcat which took part in defense of Wake Atoll as well as Battle of Midway. Its successor - remarkably good F6F Hellcat - became a legend for being the best carrier-based fighter in the mentioned conflict. The line was continued by F8F Bearcat which entered the service at the end of war but did not manage to take part in combat. The Grumman Company continued the tradition of designing excellent carrier-based aircrafts after the war, in the jet era. Surely, the two most recognizable jets from Grumman's stable were supersonic F-14 Tomcat (with variable-sweep wing) and A-6 Intruder. In the second half of the thirties, Grumman developed a line of carrier-based biplanes. A very good SF-1 started the series. It was the first American fighter with retractable undercarriage. SF-1 became the base for the F2F fighter. After lengthening of the fuselage and increasing the wings bearing surface it quickly became the F3F version. Every next model was better than previous. The F4F was planned next, also as the biplane, but during the construction the conception was changed and engineers decided to apply the mid-wing airframe. It started the long line of superb Grumman's fighters. The new aircraft was tested in air on the 2nd of September 1937. The first serial planes, marked as F4F-2, were manufactured from August 1939. The plane had innovative wing folding system which put both wings along the fuselage to minimize the space needed to store it in carriers' hangar. This unique mechanical solution became one of the hallmarks of Grumman's planes. Interestingly, the undercarriage was retracted manually by the pilot with the help of a special crank installed in the cockpit. The name "Wildcat" was used for the first time in 1941.