Mooney M20M, Pilot Operating Handbook

Page: 257 / 377

GI 275 Part 23 AML STC
190-02246-12 Rev. 4
Airplane Flight Manual Supplement Page 17 of 70
FAA APPROVED
Navigation Angle
The Magnetic/True Navigation Angle (as selected in the MENU → SYSTEM
→ UNITS Page) must match the navigation angle selected on all interfaced
GPS/SBAS navigators. If this is not done the navigation deviations will not be
accurate.
ADAHRS Normal Operating Mode
The ADAHRS integrity monitoring uses GPS data and air data. Since the
internal ADC provides full time air data, the only required external input is from
an approved and installed GPS.
A system message will be generated if the ADAHRS has not received GPS
aiding.
NOTE
GI 275 attitude will remain valid if either GPS or Air Data is
lost.
Dispatch into IFR flight is not authorized unless the Primary GI
275 ADAHRS is receiving valid GPS
and air data. The GI 275
monitors the integrity of these systems automatically and will
advise the pilot if the GPS and/or air data is lost or invalid.
NOTE
In dual GPS installations, only one GPS needs to be available
to the ADAHRS or AHRS for IFR flight.
Aerobatic Maneuvers
Do not conduct aerobatic maneuvers if the GI 275 is installed and being used as
a primary or standby ADI. If aerobatic maneuvers are to be conducted, it is
recommended that the GI 275 power be removed. Power can be restored and
normal operations conducted once the aerobatic maneuvering is complete.
Electronic Standby and/or Primary Instrument Power
For IFR aircraft, the backup battery’s charge state for the standby and/or
primary instrument must be verified before flight. The battery indication turns
yellow if there is less than 60 minutes of battery capacity. For aircraft with
service ceilings below 25,000 ft, only 30 minutes of backup battery operation is
required. For aircraft with a service ceiling above 25,000ft, 60 minutes is
required. Refer to the battery status and information found in the battery menu
(Menu → Systems → Battery). Refer to section 4.1.1 for more information.