The concept of floatplanes first came into use during World War I, during which both the United States Navy and the Royal Navy began to utilize them for reconnaissance, anti-submarine warfare, as well the air-sea rescue role. By the late 1930's floatplanes were in wide use among the world's navies with the U.S. Navy in need of a monoplane float design, capable of performing a number of missions, launched from both land bases and capital ships. The answer to this requirement proved to be one of the most versatile floatplanes of World War II, the Chance-Vought OS2U Kingfisher.
While there were several types of scouting aircraft available to the U.S. Navy at the beginning of World War II, the O2U Kingfisher was to prove the most useful, as well as the most durable. The Kingfisher design incorporated a number of revolutionary structural techniques to include spot welding. The Kingfisher was based upon the Vought company's considerable experience with observation aircraft and was designed to replace earlier Vought biplanes in a similar role. The layout of the fuselage was similar to that of the earlier biplane scouts, as was the use of a single large float plus underwing stabilizing floats. Alternatively, a conventional tail wheel undercarriage could be fitted. Before both seaborne and airborne radar were widely utilized, naval scout/reconnaissance planes were the primary source of observation for the fleet. Operating from cruisers and battleships, these aircraft observed enemy ship movements, directed gunfire from their own ships, and performed air-sea rescue missions.
The Navy's aging and overextended inventory of O2U-1 Corsair scout/observation biplanes were in need of replacement. In 1937, the Navy requested bids for a new dual-purpose scout aircraft that could be operated from either land or water, and be catapulted from cruisers and battleships. Chance-Vought's entry, the XOS2U-1, was a radical departure from the other entries. It was a two-place mid-wing monoplane, powered by a 450 hp. Pratt & Whitney R-985-4 nine cylinder Wasp engine. Though the XOS2U-1 was initially designed as a land plane, the addition of a single main float and wing-tip floats gave it a seaplane capability. Vought was awarded the production contract by the Navy in early 1937, with the first flight taking place on July 20 of that year. The Kingfisher was the first aircraft to be assembled with spot welding, a process Vought and the Naval Aircraft Factory jointly developed to create a smooth fuselage which resisted buckling and created less drag. The Kingfisher had other innovations, such as the use of high lift devices and spoilers, with deflector plate flaps and drooping ailerons located on the trailing edge of the wing to increase its camber and create additional lift. The OS2U was armed with a forward firing .30-caliber Browning M1919 machine gun, the receiver mounted low in the right front cockpit, firing between the engine cylinder heads, while the radio operator/gunner manned another .30-caliber machine gun (or a pair) on a flexible Scarff ring mount. The OS2U was also capable of carrying either two hundred pound bombs or two 325 lb. depth charges.
In August 1940, the first production run of 54 Kingfishers were delivered to the United States Navy. The following year 158 examples were delivered to the Navy, with 103 aircraft assigned to training roles, while 53 aircraft were assigned to Naval Air Station, Jacksonville to conduct anti-submarine patrols off the east coast of Florida. In the sea-based mode, Kingfishers were launched from capital ships and retrieved by use of a sea sled towed just below the surface and played out in waters smoothed by the ship's wake. The aircraft would land in the wake, taxi to the sled and engage it with a small hook on the bottom of the float before being craned aboard.
When the United States entered World War II, the Kingfisher was already the predominant floatplane of the USN. The Kingfisher was not only produced for the Navy, but seventy-six examples were delivered to the United States Coast Guard, beginning in March 1942. During the course of the war, OS2Us were delivered to allied nations to include Britain, Australia and the Soviet Union.
The Kingfisher was used extensively for air-sea rescue , artillery spotting and conducting aerial patrols during World War II. With a range of 745 miles, a maximum speed of 174 mph. and a cruising speed of 132 mph., the Kingfisher was the ideal aircraft for conducting both long-range fleet patrols and anti-submarine patrols. However, the most notable missions of the OS2U were several air-sea rescue missions . One of the most daring missions occurred on November 11, 1942 when a Kingfisher piloted by Lt. JG FE Woodward and AR1 LB Boutte found and rescued a B-17 crew, who went off course in October 1942. The crew, including World War I ace Capt. Eddie Rickenbacker, remained adrift for three weeks. Unable to transport the entire crew inside the plane, Woodward lashed Rickenbacker and another man to his wing and taxied them some forty miles to land. In another dramatic rescue in April 1944, Lt. Junior Grade John Burns landed in rough seas several times to rescue 10 downed aviators at Truk. During one rescue, the men sitting on his wings or in the cockpit, made his aircraft too heavy to take off. Burns instead taxied through several miles of heavy sea to reach a submarine, for which Burns was awarded the Navy Cross, proving the durability of the Kingfisher. A Kingfisher was even credited with shooting down a Japanese Zero during the Iwo Jima campaign. Some 1,519 Kingfishers were built before production ceased in 1946. They were a capable plane, earning the respect of all who flew them, though its mission was short-lived. By the late 1940's, the U.S Navy began to launch helicopters from both aircraft carriers and capital ships, ushering in a new era of naval aviation.