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How do birds fly? – All about Aircraft
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How do birds fly?
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Main Sections @ The Billion Dollar Site
For all aircraft related questions see the All about Aircraft section.
How do birds fly?
This page explains bird flight in a simple and elegant manner
Flight - From Wikipedia, the free encyclopedia
Flight is the process by which an object achieves sustained movement either through the air by aerodynamically generating lift or aerostatically using buoyancy, or movement beyond earth's atmosphere, in the case of spaceflight.
Contents
1 Animal flight 2 Mechanical flight 3 Forces in Flight 4 In fiction 5 See also
Animal flight
The most successful groups of living things that fly are insects, birds, and bats. Each of these groups' wings evolved separately from different structures. See also Bird flight.
Pterosaurs were a group of flying vertebrates contemporaneous with the dinosaurs.
Bats are the only mammals capable of true flight. However, there are several gliding mammals which are able to glide from tree to tree using fleshy membranes between their limbs; some can travel hundreds of metres in this way with very little loss in height. Flying tree frogs use greatly enlarged webbed feet for a similar purpose, and there are flying lizards which employ their unusually wide, flattened rib-cages to the same end. Certain snakes also use a flattened rib-cage to fly, with a back and forth motion much the same as they use on the ground.
Flying fish can glide using enlarged wing-like fins, and have been observed soaring for hundreds of metres using the updraft on the leading edges of waves. It is thought that this ability was chosen by natural selection because it was an effective means of escape from underwater predators.
Most birds fly (see bird flight), with some exceptions. The largest birds, the ostrich and the emu, are earthbound, as were the now-extinct dodos, while the non-flying penguins have adapted their wings for use under water. Most small flightless birds are native to small islands, and lead a lifestyle where flight would confer little advantage. The Peregrine Falcon is the fastest animal in the world; its terminal velocity exceeds 370 km/h (199 mph) in a dive.
Among living animals that fly, the wandering albatross has the greatest wingspan, up to 3.5 metres (11.5 feet); the great bustard has the greatest weight, topping at 21 kilograms (46 pounds).
Among the many species of insects, some fly and others do not (See insect flight).
Mechanical flight
Mechanical flight is the use of a machine, called an aircraft, to fly. These machines include Kites,helicopters, autogyros, airships, balloons, and spacecraft. Gliders provide unpowered flight. Another form of mechanical flight is parasailing. This occurs by a parachute like object being pulled by a boat.
The most common form of mechanical flight is aeroplane flight. Several steps are involved:
Planning, Taxiing, Take off, Climbing, Cruising, Loiter Descending, and Landing. See aviation history and First flying machine for the history of mechanical flight.
Forces in Flight
Several forces are particularly important for flight:
Propulsive thrust: (except in gliders) Lift: Created by wings Drag: Created by airflow Weight: (created by gravity) Buoyancy: for lighter than air flight
Credits & Copyright: This page is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article Flight
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