A floatplane is a type of

seaplane A seaplane is a powered fixed-wing aircraft capable of takeoff, taking off and water landing, landing (alighting) on water.Gunston, "The Cambridge Aerospace Dictionary", 2009. Seaplanes are usually divided into two categories based on their tec ...

with one or more slender floats mounted under the fuselage to provide

buoyancy Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the pr ...

. By contrast, a

flying boat A flying boat is a type of fixed-winged seaplane with a hull, allowing it to land on water. It differs from a floatplane in that a flying boat's fuselage is purpose-designed for floatation and contains a hull, while floatplanes rely on fuselag ...

uses its fuselage for buoyancy. Either type of seaplane may also have landing gear suitable for land, making the vehicle an

amphibious aircraft An amphibious aircraft or amphibian is an aircraft (typically fixed-wing) that can take off and land on both solid ground and water, though amphibious helicopters do exist as well. Fixed-wing amphibious aircraft are seaplanes (flying boats ...

. British usage is to call "floatplanes" "seaplanes" rather than use the term "seaplane" to refer to both floatplanes and

Use

Since World War II and the advent of helicopters, advanced

aircraft carrier An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for Carrier-based aircraft, carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a ...

s 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 A bush airplane is a general aviation aircraft used to provide both scheduled and unscheduled passenger and flight services to remote, undeveloped areas, such as the Canadian north or bush, Alaskan tundra, the African bush, or savanna, Amazon ra ...

, 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 A charter is the grant of authority or rights, stating that the granter formally recognizes the prerogative of the recipient to exercise the rights specified. It is implicit that the granter retains superiority (or sovereignty), and that the rec ...

basis (including pleasure flights), provide scheduled service, or be operated by residents of the area for private, personal use.

Design

Float planes have often been derived from land-based aircraft, with fixed floats mounted under the fuselage instead of retractable

undercarriage Undercarriage is the part of a moving vehicle that is underneath the main body of the vehicle. The term originally applied to this part of a horse-drawn carriage, and usage has since broadened to include: *The landing gear of an aircraft. *The c ...

(featuring wheels). Float planes offer several advantages since the

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft ...

is not in contact with water, which simplifies production by not having to incorporate the compromises necessary for water tightness, 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 the 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. Floats inevitably impose extra drag and weight, rendering floatplanes slower and less manoeuvrable during flight, with a slower rate of climb, relative to aircraft equipped with wheeled landing gear. Nevertheless,

air race Air racing is a type of motorsport that involves airplanes or other types of aircraft that compete over a fixed course, with the winner either returning the shortest time, the one to complete it with the most points, or to come closest to a previ ...

s devoted to floatplanes attracted much attention during the 1920s and 1930s, most notably in the form of the

Schneider Trophy The Coupe d'Aviation Maritime Jacques Schneider, also known as the Schneider Trophy, Schneider Prize or (incorrectly) the Schneider Cup is a trophy that was awarded annually (and later, biennially) to the winner of a race for seaplanes and flying ...

, not least because water takeoffs permitted longer takeoff runs which allowed greater optimization for high speed compared to contemporary airfields. There are two basic configurations for the floats on floatplanes: * "single float" designs, in which a single large float is mounted directly underneath the fuselage, with smaller stabilizing floats underneath the wingtips, on planes like the

Nakajima A6M2-N The Nakajima A6M2-N (Navy Type 2 Interceptor/Fighter-Bomber) was a single-crew floatplane based on the Mitsubishi A6M Zero Model 11. The Allied reporting name for the aircraft was Rufe. Design and development The A6M2-N floatplane was devel ...

and; * "twin float" designs, with two main floats mounted side by side outboard of the fuselage. Some early twin float designs had additional wingtip stabilizing floats. The main advantage of the single float design is its capability for

landing Landing is the last part of a flight, where a flying animal, aircraft, or spacecraft returns to the ground. When the flying object returns to water, the process is called alighting, although it is commonly called "landing", "touchdown" or ...

s in rough water: a long central float is directly attached to the fuselage, this being the strongest part of the aircraft structure, while the smaller floats under the outer wings provide the aircraft with lateral stability. By comparison, dual floats restrict handling, often to

wave In physics, mathematics, and related fields, a wave is a propagating dynamic disturbance (change from equilibrium) of one or more quantities. Waves can be periodic, in which case those quantities oscillate repeatedly about an equilibrium (re ...

s as little as one foot (0.3 metres) in height.NASM research
However, twin float designs facilitate

mooring A mooring is any permanent structure to which a vessel may be secured. Examples include quays, wharfs, jetties, piers, anchor buoys, and mooring buoys. A ship is secured to a mooring to forestall free movement of the ship on the water. An ''anc ...

and boarding, and – in the case of

torpedo bomber A torpedo bomber is a military aircraft designed primarily to attack ships with aerial torpedoes. Torpedo bombers came into existence just before the First World War almost as soon as aircraft were built that were capable of carrying the weight ...

s – leave the belly free to carry a

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, su ...

References

External links

"Why Seaplanes Fly With Bullet Speed", December 1931, Popular Science
excellent article on the different design features of the floats on floatplanes
"Will a Lake Be Your Postwar Landing Field?"
''Popular Science'', February 1945, pp. 134–135. {{Authority control

Use

Design

See also

References

External links