In Aviation, when taking off the runway with a jet, the A/C goes through 4 segments of climb. Define them pls?

First segment is defined as the segment from liftoff to the point where the gear is fully retracted with flaps in the takeoff setting. It's flown at V2 speed.





Second segment is from the gear up point to 400' AGL also flown with takeoff flaps and at V2 speed.





Third segment is the distance required to go from the end of the second segment climb at V2 to the final climb speed with the flaps retracted. It's flown level while accelerating.





Final segment is from the end of the third segment till 1500' AGL. It's flown at final climb speed with flaps retracted.

In Aviation, when taking off the runway with a jet, the A/C goes through 4 segments of climb. Define them pls?
I would say really only three...





1. ROTATION- When the front gear leaves the runway...





2. CLIMB OUT- A steep ascent to clear any obstacles





3. CLIMB- Simply an ascent to cruising altitude...





I suppose one could consider the climb below 10,000 and the climb after 10,000 two separate things since there is a speed limit below 10,000... or maybe the climb under 18,000 and the climb after 18,000 separate because 18,000 is tranisition altitude... but really, nothing changes all that much at these altitudes...
Reply:I always thought spool up was the 1st part? Maybe I'm wrong or up to the individual.