Definition
The phase of flight in which an aircraft transitions from ground roll to airborne flight, beginning with the application of takeoff power on the runway and ending when the aircraft has climbed to a safe altitude and configuration for the departure phase.
Plain English
The act of getting the aircraft off the ground and into the air, starting with the roll down the runway and ending once the aircraft is safely climbing away.
Context Anchor
Seen in departure discussions, flight planning, runway operations, and instrument flight procedures.
Derivation
From the everyday phrase "to take off" — to leave or depart suddenly. In aviation it became the standard term for the moment an aircraft leaves the ground.
Why Pilots Care
Takeoff performance calculations, runway requirements, and departure procedures directly affect whether an IFR flight can safely begin.
Intuition Check
Do not read take off as simply “start moving.” In aviation, the key point is that the aircraft leaves the surface and begins flight.
Example Sentence 1
After receiving takeoff clearance, the pilot lined up on the runway and advanced the throttle to begin the takeoff roll.
Example Sentence 2
In low visibility, the crew verified takeoff minimums before beginning the takeoff roll.