Autopilot Flashcards
Autopilot
How does the AFDS control the flight control surfaces?
Via fly-‐by-‐wire control system.
When does the autopilot control the rudder?
Only during APP & LDG.
Where are the autopilot mode engagements indicated?
FMA blocks on the PFD.
Which autopilot modes have an arming phase?
- Roll modes: o LNAV. o LOC. o ROLLOUT.
* Pitch modes: o VNAV. o G/S. o FLARE.
Which mode cannot be disengaged by selection of another mode?
APP mode after LOC or G/S capture.
After ILS capture and above 1500’, what happens if APP mode is reselected?
APP mode deselects and AFDS reverts to default roll & pitch modes
When will override of the rudder pedals cause autopilot disengagement?
Only W/ LAND 2 or LAND 3 annunciated.
What will occur with a continued autopilot mode degradation?
A/P remains engaged in an attitude stabilising mode initially (degraded mode) followed by the display of an amber line through the associated mode and finally an EICAS message AUTOPILOT.
How is the flight director affected by a mode degradation?
F/D initially command an attitude stabilising command based on inertial data. If degradation continues, individual F/Ds (roll/pitch) disappear until degradation no longer detected.
With the flight directors OFF, will a TOGA selection cause them to appear?
Yes if TOGA armed for a GA, airspeed > 80kts and flaps are out of up.
What protections will cause the flight director bars to disappear?
• F/D mode failure in either pitch or roll causes the respective F/D bar to disappear. • Stall & overspeed protection functions cause pitch F/D to disappear.
During an autoland, will a degradation to LAND 2 be displayed on EICAS?
Yes, unless ACFT is BLW 200’ (to limit distraction on short final [transition to NO AUTOLAND is never inhibited]).
EICAS message displayed for any fault which limits capability of the automatic LDG system.
What two occasions will cause a green box to appear around an FMA mode?
• When a mode is first activated/engaged (green box appears for 10s). • When amber line through a degraded mode is removed (green box appears for 10s).
What is the autothrottle controlling to when THR is annunciated?
A/T applies thrust to maintain V/S REQD by pitch mode.
At what distance to the active route leg will LNAV engage, if armed?
2.5nm.
What are the conditions for the roll mode ATT to engage?
If A/P or F/D engaged W/ bank angle > 5o.
When is TOGA mode armed in flight?
Whenever flaps are out or G/S captures.
When does ROLLOUT mode engage?
BLW 2’ RA on LDG (displayed BLW 1500’ RA).
After a TOGA takeoff, what is the maximum speed the pitch mode will command?
V2 + 25.
Where does the AFDS get the V2 speed; MCP or CDU?
AFDS uses the speed set in the MCP IAS/MACH window.
When will VNAV engage if armed for takeoff?
400’.
After an altitude conflict, how is the VNAV ALT mode cancelled?
By changing the altitude value set in the MCP ALT window and pushing the ALT selector, or changing the pitch mode.
When does the FLARE mode engage?
During autoland between 60 – 40’ RA.
Can the autothrottle be operated without the flight director or autopilot?
Yes (in this condition, A/T operates in THR REF, SPED, HOLD or IDLE modes).
