Do the computers in the aircraft calculate the V speeds(V1, V2, etc) for every flight according to the ambient weather and loading conditions and display them on the PFD or they remain fixed values..??
Hi SAHIL,
FMGC (Flight Management and Guidance Computer) computes takeoff, approach and go-around speeds based on the actual "operational environment" (weather, weight, conf etc.) as well as Flight Augmentation Computers (FAC's) do in calculating minimum and maximum speeds, maneuvering speeds etc. Nowdays a TOS (Takeoff Securing Functions) is being implemented on new Airbus a/c, whose purpose is to automatically check consistency of several take-off parameters, inserted into the FMGC.
When we change the the attitude of the aircraft, does the auto throttle adjust the power of the engines to maintain the airspeed/mach no. ?
In very short form, there're 2 ATHR modes: MACH/SPEED mode and THRUST mode, so it depends on what mode is active at the moment.
Does the throttle lever move or does it stay fixed when auto thrust is in operation??
It does not move on Airbus, as a matter of fact it is an Autothrust Sys and not Autothrottle Sys.
During landing, do we set the Auto throttle to the approach speeds or do we manually control the throttle?
It depends on whether the ATHR is active or not.
Flying the aircraft manually at high speeds will cause discomfort to the passengers behind...at what time do we first enable the autopilot???
Autopilot damps oscillations and, most of the times, is far more accurate than pilot itself: thus usually hand-flying turns out to be less comfortable than auto-flight. On Airbus, autopilot is normally available 5 seconds after lift-off (100 ft) then it can be engaged right away: though the MIN ALT for AP engagement changes with every Company's SOP.
Hope this helps,
fredgrav