From Airbus "Getting to Grips with Aircraft Performance"
4.1.2. Takeoff Segments and Climb Requirements
(Figure C16)
Shows first segment starting at 35feet screen hight with speed V2 and second segment starting at gear retracted, also V2
but then also:
(Table C4)
First Segment
starts: Vlof reached
speed: Vlof
Second Segment
strats: Gear fully retracted
speed: V2
So Iīm not sure exactly whre it starts but thatīs what the book says. If anyone could explain?
The start of the takeoff run (brake release) is only considered for the takeoff distance, not part of the Takeoff segments.
Also, the takeoff is broken down into 3
PHASES:
Ground acceleration (from Brake release to start of rotation)
Rotation (From start of rotation until airborne)
Airborne acceleration (after liftoff)