Calibration/Checks; Attitude/Heading Calibration Tests - Garmin GI 275 Installation Manual

5.7 Calibration/Checks

This section provides guidance for calibrating the GI 275 system after the configuration steps have been
completed.
5.7.1

Attitude/Heading Calibration Tests

The connected AHRS will not provide valid outputs until the calibration procedures in this section are
completed. Prior to completing the Pitch/Roll Offset Compensation (Section 5.7.1.2) and Magnetometer
Calibration (Section 6.4.1) procedures, the annunciation "CALIBRATE AHRS/MAG" will be displayed
on the ADI, and the attitude and heading will be displayed. Once the aircraft is moved, the attitude and
heading display will show a red "X". This condition is normal and will automatically clear when the two
aforementioned calibration procedures are completed.
5.7.1.1 Calibrate Yaw Offset
If required for the installation, set the yaw offset. The range is -15.0 and 15.0 and the default is 0.
5.7.1.2 Calibrate Pitch/Roll Offset
This procedure must be completed on each GI 275 with an integrated ADAHRS. This procedure can be
conducted for each AHRS simultaneously on each display. The aircraft must be leveled to within 0.25° of
zero pitch and zero roll using the procedures in the aircraft maintenance manual or AFM/POH. The
following procedures must be completed with the engine off:
1. Navigate to the Calibrate Pitch/Roll page (Calibration/Test → Attitude/Heading → Calibrate
Pitch/Roll).
2. Complete the steps listed on the display. Touch the Start button to begin the calibration procedure.
3. Follow the on-screen command prompts.
The magnetometer calibration and compass swing are completed after the initial Engine Run-up Test has
been completed. Refer to Section 6.4.1.
5.7.1.3 Manual Pitch/Roll
Allows the pitch and roll values to be set manually.
5.7.1.4 Engine Vibration Test
Refer to Section 6.4.3 for test procedure.
5.7.1.5 Interference Test
Refer to Section 6.4.4 for test procedure.
5.7.1.6 Calibrate Magnetometer
Refer to Section 6.4.1 for the magnetometer calibration procedure and Section 6.4.5 for guidance on site
evaluation of magnetic disturbances
190-02246-10
Rev. 11
GI 275 Part 23 AML STC Installation Manual
Page 5-68