DSC Autoflight Flashcards
What is the low energy alert ?
Computed by the FAC.
Generate an aural low energy “SPEED SPEED SPEED” alert that repeat every 5sec.
=> warn crew of the need to increase thrust to regain positive flight path angle through pitch control.
When is the low energy alert available ?
in config 2,3 and FULL based on A/C config, horizontal deceleration and flight path angle
What is a good gross error check for calculating green dot ?
Neo a321 below 15000ft, 1,5x Weight in tonnes +110
Others below 20000ft 2x weight +85
FCOM DSC 22-10_50-20
Why can you have discrepancy between VAPP on the FMGC and the one displayed on PFD ?
It link to the way the GW is calculated.
The FAC will use FMS inserted gross weight initially but will computes its own based on aerodynamic data for the approach.
Can you explain the function of GS mini ?
The system ensures that the ground speed that the aircraft touches down with is maintained
throughout the approach, despite varying wind conditions.
It ensure standard aerodynamic margin VS stall
If you loose one FMGC what do you expect to see on the PFD and what impact on the ND ?
1FD1 or 2FD2
message on ND : SET OFFSIDE RNG/MODE or OFFSIDE FM control
What methods does the aircraft have to calculate its position ?
MIX IRS position
Computed radio position
GPS position
What is the aircraft FM position comprised of ?
Mix IRS and GPS position
With a loss FMGC how do you recover the radionavigation ?
Use the backup nav key on the RMP to manually tune radio nav.
For ALT planning, what assumptions are made regarding flight level and speed by the FMGC in terms of fuel brun ?
CI 0
FL100 if less than 100NM
FL220 if between 100NM-200NM
What is SRS ?
Speed reference system, control the speed via the elevator. => Adjust the pitch to maintain a speed
On takeoff target is V2+10
What are the protection associated with SRS ?
- Flight path angle => Mini VS 120ft/min
- Pitch angle protection => Reduce A/C nose up
- Speed limiting => limiting target speed to V2+15kt
What is the two ENG operative range of the ATHR ? And single ENG ?
two : Idle to CLB
single: idle to MCT
With ATHR failure what FMA would you expect to see while in cruise ?
THR LCK
What is the guidance for selecting REV thrust if one THRUST Rev is inop ?
Select both