The Vought OS2U Kingfisher is a catapult-launched observation floatplane designed and produced by the American aviation company Vought. It was the primary shipboard observation seaplane operated by the United States Navy (USN) during World War II, Designed as a successor to biplane observation aircraft then in use with the USN, the Kingfisher was a compact mid-wing monoplane furnished with a large central float and compact stabilizing floats. In addition to the standard float arrangement, it could also be furnished with wheeled, taildragger landing gear. The Kingfisher was the first aircraft to use spot welding in its manufacture, which produced a smooth fuselage resistant to buckling and resulted in lower-than-average drag for the era. It was typically outfitted with a Pratt & Whitney R-985 Wasp Junior radial engine. The Naval Aircraft Factory OS2N was the designation of the OS2U-3 aircraft built by the Naval Aircraft Factory in Philadelphia, Pennsylvania. An initial prototype was ordered by the USN on 22 March 1937 and performed its maiden flight on 22 July 1938.[1] The Kingfisher was commonly noted for its favourable performance at low speeds, which was a product of its use of high-lift devices and spoilers, as well as its relatively low drag. First delivered to the USN in early 1940, the Kingfisher was commonly flown from the service's capital ships to support activities such as shore bombardments and air-sea rescue. Throughout World War II, the type was primarily used in the Pacific Theatres.[2] It remained in frontline use throughout the conflict, with its replacement only beginning to enter service in 1944. Various other operators also flew the Kingfisher, including the United States Marine Corps (USMC) in Marine Scouting Squadron Three (VMS-3), and the United States Coast Guard (USCG) across its coastal air stations. Overseas operators of the OS2U included the Fleet Air Arm (FAA) of the Royal Navy, the Royal Australian Air Force (RAAF), and the Soviet Naval Aviation. Several of these nations were supplied the type under the Lend-Lease program.[2]
