Systems Guide

Aerosoft
Airbus A320/A321
SYSTEMS
Systems guide
Vol
4
04-03-12
28 October 2014
AUTOPILOTS
ENGAGEMENT
The autopilot (two identical systems) are engaged by the AP1 and AP2 pb on the FCU. When engaged a green bar
will show on the pb and the appropriate FMA annunciation is displayed. When a flight director is on when the
autopilot is engaged, the autopilot engages in appropriate mode (OP CLMB and NAV) otherwise it will engage in
the default guidance modes (HDG and V/S or TRK-FPA).
Either autopilot can be engaged seconds after takeoff.
DISENGAGEMENT
Disengage the autopilot by depressing the AP1 or AP1 button.
 The autopilot is automatically disengaged by moving the side stick (or rudder pedals) a certain amount.
This will trigger a master warning.
 The autopilot is automatically disengaged when the throttles are set above FLX/MCT on ground.
 The autopilot is automatically disengaged when a normal law is exceeded or pitch or bank angle are
excessive.
 The autopilot is automatically disengaged during a non-precision approach when the aircraft reaches
MDA minus 50 feet .
AUTOPILOT & SPEED BRAKES
With the autopilot engaged the speed brakes are limited to ½ deflection. When autopilot is engaged with speed
brakes extended beyond ½ they will retract to ½. Note this will cause a sudden pitch up.
AUTOTHRUST
The autothrust system reduces workload for the pilot, provides additional comfort for the passengers and
reduces fuel use. Two main modes are included:
 Fixed Thrust Modes
o Uses constant thrust; airspeed is controlled with pitch. Normally used for level changes when no
specific vertical speed is required.
 Variable Thrust Modes
o In variable thrust mode the airspeed remains constant by changing the amount of thrust.
Normally used for level flight or when a certain airspeed is required during level change.