Garmin G3X Installation Manual page 465

31.4.3.3 Calibration Procedure B: Pitch/Roll Offset Compensation by Aircraft Leveling.
NOTE
This procedure requires orienting the aircraft to normal flight attitude (can be done by
using jacks or placing wood blocks under the nose-wheel, for example). As another
example, if the number of degrees 'nose high' the aircraft flies in straight and level cruise
is known, a digital level can be used to orient the aircraft to normal flight attitude prior to
the calibration.
NOTE
The GSU 73 must be installed to be level within 3.0 degrees of the aircraft in flight level
cruise attitude. In flight level cruise attitude is not necessarily the same as the level
reference provided by the manufacturer (such as fuselage longerons).
NOTE
The GSU 25 must be installed to be level within 30.0 degrees of the aircraft in flight level
cruise attitude. In flight level cruise attitude is not necessarily the same as the level
reference provided by the manufacturer (such as fuselage longerons).
1. Enter configuration mode by holding down the left-hand softkey while powering on the PFD 1
display (if needed).
2. Use the FMS Joystick to select the AHRS Page (if needed).
190-01115-01 G3X/G3X Touch Installation Manual - GDU 37X Config and Post Install Checkout
Rev. AA
Figure 31-2 Flight Level Cruise Attitude
Page 31-13