A flying boat is an aircraft which is designed to take off and land on water. It is a type of seaplane, distinguished from floatplanes by the lack of pontoons. On a flying boat, the hull of the aircraft is used to provide buoyancy and flotation, although stabilizers may be attached to the hull or the wings to keep the aircraft balanced in the water. This differs from the pontoon design, in which the plane lands on a set of pontoons which also stabilize the craft. It is necessary to have a pilot's license to handle a flying boat.
The heyday of the flying boat was in the 1920s and 1930s, when a number of different nations invested in research and development of these aircraft. The flying boat was seen as an ideal solution for long distance travel such as trans-Atlantic travel, and it was also seen as a potentially very valuable rescue craft. Aircraft designers could also see other potential uses, such as island hopping in remote archipelagos.
One thing about many flying boats built in the early 20th century is that they were much larger than land-based aircraft designed at the time. Flying boats could be big because they didn't require specialized runways, with the capability to set down in any large body of water. They were also designed big to carry a large load of fuel for the purpose of long trips, although they could touch down near a ship to refuel when necessary. Several aircraft companies believed that the flying boat was the future of aviation, and distributed their research and development funds accordingly.
When the Second World War broke out, many governments invested in the development of flying boats for military use. These aircraft proved to be especially useful in the Atlantic, where they were used by the Allies to harry the German U-boats. With the close of the war, however, interest in flying boats waned, and aircraft manufacturers began to focus on land-based aircraft.
Several companies continue to manufacture flying boats and floatplanes which are utilized in a variety of locations around the world. Many are small aircraft, used for things like mail delivery in remote locations, travel along island chains, and so forth. While the design has been supplanted in popularity by that of a land-based aircraft, the flying boat still has some applications, and some manufacturers have even developed amphibious designs which can be used on land or on sea.