Liftoff is the point during a launch or takeoff roll when the vehicle's upward thrust or aerodynamic lift exceeds its weight, causing the landing gear or launch mounts to separate from the surface. For rockets, it marks the transition from ground support to autonomous flight. For aircraft, it is the moment the main wheels leave the runway.
Heard on the job
We have main engine ignition, and we have liftoff of the Atlas V rocket.
Also heard as
- lift-off
Related terms
Touchdown
The exact moment an aircraft or spacecraft makes contact with the landing surface.
Launch window
The specific timeframe during which a spacecraft must lift off to reach its intended orbit or target.
T-minus
A countdown protocol indicating the time remaining before a scheduled launch or major sequence.