Abnormal Procedures
5-7
LOSS OF AHRS (SINGLE PFD EQUIPPED AIRCRAFT)
Failure Indication:
A failure of an AHRS is identified by Red-Xs over the attitude and
HSI compass card and an autopilot disconnect (if previously
engaged).
Additionally, a yellow “
AUTOPILOT INOP AHRS
FAIL
” message is displayed in the center of the autopilot mode
annunciator area on the PFD.
Functionality Lost:
A loss of AHRS will result in a loss of all autopilot functionality.
Recommended Pilot Action:
Immediately transition to hand-flying via the standby instruments
and seek VMC as soon as feasible.
Consider attempting a single PFD warmstart by cycling both PFD
circuit breakers for less than 20 seconds (if Avidyne PFD
equipped).
LOSS OF AHRS (DUAL AVIDYNE PFD EQUIPPED AIRCRAFT)
Failure Indication:
A failure of an AHRS is identified by Red-Xs over the attitude and
HSI compass card. If the cockpit ADAHRS source selection
switch is set to the PFD with the failed AHRS, then the autopilot
will disconnect
and a yellow “
AUTOPILOT INOP AHRS FAIL
”
message is displayed in the center of the autopilot mode
annunciator area on the PFD.
Functionality Lost:
As soon as the cockpit ADAHRS source selection switch is set to
the fully functional PFD, there is no loss of any autopilot
functionality.
Recommended Pilot Action:
Manually set the cockpit ADAHRS source selection switch to the
fully functional PFD and then re-engage the autopilot in the
desired modes.
Change 3