Mooney M20M, Pilot Operating Handbook

Page: 266 / 377

GI 275 Part 23 AML STC
190-02246-12 Rev. 4
Airplane Flight Manual Supplement Page 26 of 70
FAA APPROVED
3.1.2 AHRS Failure
AHRS failure is indicated by the removal of the attitude/heading information and
a red X on the GI 275 ADI. Standard rate turn indications will also be removed. A
heading failure may also occur as described in Section 3.2.1.
1. Continue flight by reference to the standby ADI or manually select “ON”
on the GI 275 reversionary backup switch to force reversion.
2. Seek VFR conditions or land as soon as practicable if there are no other
reliable AHRS sensors capable of providing accurate data.
If multiple AHRS sources are installed:
3. Select the operative AHRS (i.e., AHRS 1, 2 or 3) using the ADI sensors
menu (MENU → SENSORS)
4. Press and hold the back button to return to the ADI page.
NOTE
If airborne AHRS alignment is necessary, minimize maneuvering
and turbulence during and after the restart process. Excessive
maneuvering or turbulence may prevent the AHRS from aligning
properly. Continue to minimize maneuvering and seek smooth air
for the first 5 minutes after the attitude becomes valid following the
airborne alignment. If maneuvering or turbulence cannot be
avoided, carefully cross-check the AHRS for accuracy against other
flight instruments until the alignment has completed and becomes
stable.
CAUTION
In installations with a Garmin cross-comparison for AHRS/ADC
sensors, changing the AHRS/ADC sensor source when a white
ATTITUDE/IAS/ALT annunciation is displayed on the primary GI
275 ADI will result in the selection of an inoperative sensor source
and subsequent loss of information. Operating primary and standby
GI 275 ADIs on the same sensor source will inhibit the
AHRS/ADC comparison monitor.