About Airport

Take off is the phase of flight in which an aircraft goes through a transition from moving along the ground (taxiing) to flying in the air, usually starting on a runway. For balloons, helicopters and some specialized fixed-wing aircraft (VTOL aircraft such as the Harrier), no runway is needed. Takeoff is the opposite of landing.

Power Settings

For light aircraft, full power is used during takeoff. Large transport category (airliner) aircraft will usually use a derated power takeoff, where less than full power is applied, with unneeded power held in reserve in case of emergency. Before takeoff, the engines, particularly piston engines, are routinely run up at high power to check for engine-related problems.

The aircraft is permitted to accelerate to rotation speed (often referred to as Vr). The term rotation is used because the aircraft pivots around the axis of its main landing gear while still on the ground, usually due to manipulation of the flight controls to make this change in aircraft attitude.

Speed Required

The takeoff speed required varies according to factors such as air density, aircraft gross weight, and aircraft configuration (flap and/or slat position, as applicable). Air density, in turn, is affected by factors such as field elevation and air temperature.

This relationship between temperature, altitude, and air density can be expressed as a density altitude, or the altitude in the International Standard Atmosphere at which the air density would be equal to the actual air density.