seaplane(redirected from Hydroaviation)
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seaplane,airplane designed to take off from and alight on water. The two most common types are the floatplane, whose fuselage is supported by struts attached to two or more pontoon floats, and the flying boat, whose boat-hull fuselage is constructed with the buoyancy and strength necessary to land and float on water. Amphibians may be of either of these types with the addition of landing gear, enabling them to take off from and alight on either land or water. The first practical seaplane was constructed and flown by the American Glenn H. Curtiss in 1911. The seaplane developed rapidly in the 1920s and 30s, and for a time it was the largest and fastest aircraft in the world. Because the flotation structures offered greater resistance to the air than wheel-type landing gear, seaplanes were until recently less efficient and slower for any given horsepower requirement than land-based aircraft. However, developments in small and retractable flotation structures have eliminated that inefficiency and have made possible supersonic jet-powered seaplanes.
an aircraft capable of being based on water and that can take off from and land on water. The general principles of aerodynamics and design for a seaplane are the same as for a land-based aircraft, but a seaplane must meet specific operational requirements: it must be stable while afloat and during takeoffs and landings, and it must be maneuverable on the water, for example. When afloat a seaplane’s weight is fully supported by a hydrostatic lifting force (which is equal in magnitude to the displacement of the seaplane’s fuselage). During the takeoff run its weight is borne by the lifting force of the fuselage’s bottom skimming across the water and by the aerodynamic lift of the wings, which enable the seaplane to become airborne when the takeoff speed is achieved. The configuration of the bottom of a seaplane’s fuselage creates a hydrodynamic lifting force and is designed to provide the seaplane stability during water runs and achieve minimal overloading and wave generation (during takeoffs and landings). A transverse lip, or planing step, on the seaplane’s bottom makes it possible for the aircraft to leave the water’s surface at takeoff speeds. The experience of hydrofoils (for example, the Soviet Be-8 seaplane) that have been designed as takeoff and landing equipment has revealed that they significantly simplify a pilot’s task during takeoffs and landings.
Seaplanes are usually built according to one of two designs: in the form of a flying boat with the crew, passengers, and necessary navigational and operational equipment located within the hull or in the form of a standard land-based aircraft equipped with flotation gear. A flying boat’s lateral stability while it is afloat is provided by pontoons under the wings or by “gills” (streamlined water-displacing devices) fastened along the sides. Seaplanes whose takeoff and landing arrangements incorporate a combination of landing gear and a boat hull or floats (amphibious aircraft) can be based on water or land.
In Russia the first float-type seaplane was built in 1911 by la. M. Gakkel’. This seaplane was awarded a grand silver medal at the International Aviation Exhibit of 1911. O. S. Kostovich was the first to design a flying boat seaplane (1911). The first flying boats in Russia (the M-l, M-4, and M-9) were built during 1913-15 under the supervision of D. P. Grigorovich. After the Great October Socialist Revolution the following aircraft designers developed the seaplane for civil and military aviation in the USSR: D. P. Grigorovich, A. N. Tupolev (the MK-1; the TB-1 and R-6, mounted on floats), G. M. Beriev (the MBR-2 short-range naval reconnaissance aircraft, the MP-1 naval passenger seaplane, the Be-2 and Be-4 shipborne catapult seaplanes, the Be-6 patrol flying boat, the Be-10 jet seaplane, and the M-12 amphibious turboprop aircraft), I. V. Chetverikov (Che-2), and V. B. Shavrov (Sh-2 amphibious aircraft). Abroad, seaplanes were built by aircraft firms in France, the USA, Great Britain, Germany, Italy, and Japan. The Soviet pilots N. I. Andrievskii and G. I. Bur’ianov set 12 international records in 1961 while flying a Be-10 seaplane. These records include speed (912 km/hr), altitude (14,962 m), and freight load (15,206 kg).
Seaplanes are being developed for freight and passenger service in areas with numerous bodies of water, for fishery reconnaissance, for air-sea rescue operations, and for fighting forest fires.
REFERENCESSamsonov, P. D. Proektirovanie i konstruktsii gidrosamoletov. Moscow-Leningrad, 1936.
Kosourov, K. F. Teoreticheskie osnovy gidroaviatsii. Moscow, 1961.
Shavrov, V. B. Istoriia konstruktsii samoletov v SSSR. Moscow,1969.
G. M. BERIEV