Take off

Take off is the phase of flight where an aircraft transitions from moving along the ground (taxiing) to flying in the air (see flight), usually from a runway. Take off is the opposite of landing.

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For light aircraft, full power is normally used during take off. Large transport category (airliner) aircraft will usually use a derated power takeoff, where less than full power is used. The aircraft is permitted to accelerate to rotation speed (often referred to as Vr) and then rotated off the ground gently. The term rotation is used, because the aircraft pivots or rotates about its the axle of it main landing gear when the flight controls are used to change the aircraft attitude. Usually the rotation is approximately 10 to 15 degrees nose up compared to the position of the nose while on the ground. Autorotation is where an aircraft will do precisely this by itself when it reaches some speed.

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Larger planes (such as commercial jet aircraft) have difficulty generating enough lift at the (comparatively) low speeds encountered during take-off. These are therefore fitted with high-lift devices, such as flaps or slats, which increase the lift of the wing at low speed. These are deployed from the front and rear edges of the wing before take-off, and retracted during climb (usually accompanied by a humming noise from the motors that move them).

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The speeds needed for takeof are relative to the motion of the air (air speed). A headwind will reduce the ground speed needed for takeoff. Typical takeoff air speeds for jetliners are in the 130 to 155 knot range (150 to 180 miles/hour, 250 - 290 km/hour.) Light aircraft, such as a Cessna 150, take off at around 55 knots (63 miles/hour, 100 km/hour). Ultralights have even lower takeoff speeds. The speed required varies according to many factors, including airport altitude, outside temperature, aircraft gross weight, power setting, and flap position. Pilots of multi-engine aircraft calculate a decision speed (V1) for each take off that dictates action to be taken in case an engine fails. Below V1 the take off is aborted; above V1 the pilot should continue to take off.

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If an obstacle needs to be cleared, the pilot lowers the nose just until the speed for maximum climb angle is achieved, Vx. If no obstacle needs to be cleared, or once an obstacle is cleared, the pilot further lowers the nose to accelerate to Vy, the speed at which climb is the most rapid. At this point the climb phase of flight begins.

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Gliders take-off using a variety of methods, (see article on gliding), but the most common methods are winching-launching and by being towed behind a light aircraft. Helicopters and some specialized fixed wing aircraft (VTOLs) can take off vertically.

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See aircraft for more information.

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Aircraft: An aircraft is any machine capable of atmospheric flight....

Taxiing: Taxiing refers to an airplane moving under its own power on the ground, usually on wheels, but also includes aircraft with skis or floats (for water-based travel)....

Flight: :This article concerns the process of flying. For other meanings see Flight (disambiguation)....

Take off related Images and Photos (experimental)

Space Shuttle Take-Off 1000 Piece Puzzle	Great Catalina Take-Off	Evangelion Vertical Take off and Landing Aircraft Model Kit	Before Take-Off a German Naval Pilot Contemplates the Mission Before Him
Helicopter About to Take off with Termite Mound at Right North of Cooktown Australia	Apartment Block with Provision for Rocket Take-Off on the Roof	Louis Bleriot Flies the Channel Landing at Dover 37 Minutes after Take-Off from Near Calais	Take, The (1974)
Take Five	Take Pride	Take Three	Take Two I