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 Landing - Definition 

fr:Atterrissage

Landing is the last part of a flight, where a flying animal or aircraft returns to the ground. Hitting the ground too hard is prevented by wings (including rotor wings), a parachute or rockets or a vertically directed jet engine; in the case of a balloon the buoyancy is slightly decreased for a soft landing.

Mytravel Airbus A320 landing
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Mytravel Airbus A320 landing

For aircraft or birds, landing is generally accomplished by trading airspeed for lift. The first phase is the flare when the rate of descent will be reduced by effectively stalling the plane, with a rotation in pitch into the landing attitude shortly before reaching the ground. The nose continues to rise which increases the angle of attack of the wings and therefore the amount of lift generated, as the airspeed gradually reduces.

Aircraft typically land at an airport.

In a perfect touchdown, assuming there is no crosswind, contact with the ground is made just as the forward speed is reduced to the point where there is no longer sufficient lift to remain aloft. If there is a crosswind, techniques such as a crab landing or a slip landing are used to land the plane safely.

During landing, the ground effect becomes significant for aircraft. This tends to make the aircraft "keep flying" when it ordinarly would not (at higher altitudes) and therefore to extend the distance required to land.

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Mute.swan.touchdown.arp.jpg
A Mute Swan landing. Note the ruffled feathers on top of the wings indicate that the swan is flying at the stalling speed. The extended and splayed feathers act as lift augmenters in the same way that an aircraft's slats and flaps do.

Large jet transport aircraft land differently to that described above. If the pilot waited for the aircraft to stall too much runway length would be used so the flare just reduces the rate of descent at touchdown and the aircraft is flown onto the runway. Usually lift dumpers are immediately deployed to dramatically reduce the lift and transfer the aircraft's weight to its wheels, where mechanical braking can take effect.

To land on an aircraft carrier, an aircraft (moving at, perhaps, 150 mph (240 km/h)) is equipped with tailhooks to engage one of up to four arresting cables stretched across the deck, stopping the aircraft within 320 feet (100 m) after engaging one of the cables.


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This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Landing".