Hi folks,
I have a question regarding the pitch channel of modern, complex autopilots.
In FLCH / VNAV / Managed Climb / Open Climb with the MCP/FCU Alt selected being higher than the current altitude, the autopilot will try to climb at a selected Air-/mach speed.
What happens if
a) the target speed is too high and the aircraft's performance is not enough to reach that speed and climb at the same time. Will the AP "settle for less" and maintain a minimal VS and accept any speed? Or will it even consider descending (hope not) to reach that speed?
b) assuming one turns off the autothrottle/autothrust and pulls the throttle/thrust levers back to idle during a climb (very stupid, I know). Will the aircraft pitch up gradually and stall or in this case start descending? I guess Airbus will in the worst case switch to alpha protection and lower the nose by its own but does the AP have a similar function? And what about Boeing and other non FBW aircraft (let's not ignore the 777
)?