Definition of times - for airlines... (and crews) -
Block OUT time, time at which airplane is pushed back, or moves.
Takeoff time, time at which power is applied for takeoff.
Landing time, time at which the aircraft lands.
time, time at which blocks are placed forward/aft of wheels at gate.
The airline schedules are based on block time (Block OUT - Block IN
ATC and flight plans use takeoff and landing times.
Flight hours for airplanes (maintenance, airplane age) is takeoff to landing.
Flight hours for crew (flight pay if applicable) is Block OUT to Block IN