The Naval Aircraft Factory (NAF) was established by the United States Navy in 1918 in Philadelphia, Pennsylvania. It was created to help solve aircraft supply issues which the Navy Department faced upon the entry of the U.S. into World War I. The United States Army’s requirements for an enormous quantity of airplanes created a decided lack of interest among aircraft manufacturers in the Navy's requirements for a comparatively small quantity of aircraft. The Navy Department concluded that it was necessary to build a Navy-owned aircraft factory in order to assure a part of its aircraft supply; to obtain cost data for the department’s guidance in its dealings with private manufacturers; and to have under its own control a factory capable of producing experimental designs.

The Vought OS2U Kingfisher is an American catapult-launched observation floatplane. It was a compact mid-wing monoplane, with a large central float and small stabilizing floats. Performance was modest because of its low-powered engine. The OS2U could also operate on fixed, wheeled, taildragger landing gear.