Definition
The airspeed at which the airplane leaves the runway during takeoff and the airspeed used for the initial climb after lift-off, as recommended by the airplane manufacturer for the specific airplane and conditions. These speeds are published in the Pilot's Operating Handbook (POH) or Airplane Flight Manual (AFM) and are selected to provide a safe margin above stall while ensuring positive climb performance and obstacle clearance.
Plain English
The speed the airplane should reach before its wheels leave the ground, and the speed it should hold while climbing away from the runway. The manufacturer chooses these speeds to keep the takeoff safe and the climb steady.
Context Anchor
Seen in normal takeoff procedures, especially when checking the airplane's operating handbook before takeoff and controlling the airplane just after it becomes airborne.
Derivation
"Lift-off" means the airplane is lifted off the ground. "Climb-out" means climbing out and away from the runway area after takeoff. Together, the phrase points to the speed used during the change from rolling on the runway to flying away from it.
Why Pilots Care
These speeds ensure enough lift to leave the runway and a safe climb rate for obstacle clearance and engine-failure options.
Intuition Check
Do not read this as one fixed speed that is the same for every airplane or every takeoff. The correct speed comes from the specific airplane's procedures and may change with weight, conditions, and runway needs.
Example Sentence 1
After accelerating down the runway, the pilot allowed the airplane to lift off at the published lift-off speed and then held the recommended climb-out speed until reaching a safe altitude.
Example Sentence 2
After becoming airborne the pilot adjusted pitch attitude to hold the lift-off and climb-out speed during the initial climb.