Background History
The first recorded design for a vehicle which could be
termed a Hovercraft was in 1716
by Emanuel Swedenborg, a Swedish designer,
philosopher and theologian. His man-powered air cushion platform resembled an
upside-down boat with a cockpit in the center and manually operated oar-like
scoops to push air under the vehicle on each downward stroke.
In the mid-1870s,
the British engineer Sir John Isaac Thornycroft built a number of ground effect
machine test models based on his idea of using air between the hull of a boat
and the water to reduce drag. Although he filed a number of patents involving
air-lubricated hulls in 1877,
no practical applications were found. Over the years, various other people had
tried various methods of using air to reduce the drag on ships.
Finnish engineer DI Toivo J. Kaario, head inspector of
Valtion Lentokonetehdas (VL) airplane engine workshop, began to design an air
cushion craft in 1931. He constructed and tested his craft, dubbed pintaliitäjä (surface glider), and
received its Finnish patents 18630 and 26122. Kaario is considered to have
designed and built the first functional hovercraft, but his invention did not
receive sufficient funds for further development.
In the mid 1930s, Soviet engineer Vladimir Levkov assembled about 20 experimental
air-cushion boats
(fast attack craft and
high-speed torpedo
boats). The first prototype, designated L-1, had a very simple design which
consisted of two small wooden catamarans that were powered by three engines. Two M-11 radial
aero-engines were installed horizontally in the funnel-shaped wells on the
platform which connected the catamaran hulls together. The third engine, also an
air-cooled M-11, was placed in the aft part of the craft on a removable
four-strut pylon.
An air cushion was produced by the horizontally-placed engines. During
successful tests, one of Levkov's air-cushion craft, called fast attack L-5
boat, achieved a speed of 70 knots or about 130 kilometers per hour.
In the US during the Second World War,
Charles J. Fletcher designed his
"Glidemobile" while a United States Navy Reservist. The design worked
on the principle of trapping a constant airflow against a uniform surface
(either the ground or water), providing anywhere from ten inches to two feet of
lift to free it from the surface, and control of the craft would be achieved by
the measured release of air. Shortly after being tested on Beezer's Pond in
Fletcher's home town of Sparta Township, New Jersey, the design
was immediately appropriated by the United States Department of War
and classified, denying Fletcher the opportunity to patent his creation. For Next Page Please Click Here
0 comments:
Post a Comment