Floatplane

A floatplane (float plane or pontoon plane) is a type of seaplane, with one or more slender pontoons (known as "floats") mounted under the fuselage to provide buoyancy. By contrast, a flying boat uses its fuselage for buoyancy. Either type of seaplane may also have landing gear suitable for land, making the vehicle an amphibious aircraft.

Since World War II and the advent of helicopters, advanced aircraft carriers and land-based aircraft, military seaplanes have stopped being used. This, coupled with the increased availability of civilian airstrips, have greatly reduced the number of flying boats being built. However, numerous modern civilian aircraft have floatplane variants, most of these are offered as third-party modifications under a supplemental type certificate (STC), although there are several aircraft manufacturers that build floatplanes from scratch. These floatplanes have found their niche as one type of bush plane, for light duty transportation to lakes and other remote areas, as well as to small/hilly islands without proper airstrips. They may operate on a charter basis (including pleasure flights), provide scheduled service, or be operated by residents of the area for private, personal use.

Floatplanes have often been derived from land-based aircraft, with fixed floats mounted under the fuselage instead of retractable undercarriage (featuring wheels).

Floatplanes offer several advantages, since the fuselage is not in contact with water, which simplifies production by not having to incorporate the compromises necessary for watertightness, general impact strength and the hydroplaning characteristics needed for the aircraft to leave the water. Attaching floats to a landplane also allows for much larger production volumes to pay for the development and production of the small number of aircraft operated from water. Additionally, on all but the largest seaplanes, floatplane wings usually offer more clearance over obstacles, such as docks, reducing the difficulty in loading while on the water. A typical single engine flying boat is unable to bring the hull alongside a dock for loading while most floatplanes are able to do so.

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