You may divided a flight into 5 flight phases . The take off, aircraft climb, cruise, decent and the landing phases.
The climb steps are listed below:
Ground level – Take off phase – power on take off – flap take off – thrust lever manual
32 ft – technically ending the takeoff phase
100 ft – Autopilot can be switched on to navigate the aircraft.
1500 ft – Climb Phase Start- power on CLB -Climb. Flap takeoff setting . Auto throttle on , speed still at V2+10
4000 ft – speed change to Climb speed, flap retraction started.
6000 ft – The altimeter baro set to the standard pressure 1013. At the lower altitude, the setting was at the airport baro pressure. So, the altimeter would indicate the height above the airport.
The climb flight phase ends when the aircraft reach the targeted cruise altitude. As the aircraft gets lighter it can go to higher level.
The climb is done with the directive from the ATC. ATC is looking through its radar system on the safe clearance with the other flying aircraft. It is normal to do the climb in steps as cleared by ATC. This is the second flight phase, where the aircraft climb to the target cruise level.
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