190-01115-01 G3X™/G3X Touch™ Avionics Installation Manual
Rev. AV Page 30-94
NOTE
It is important to make sure of proper autopilot response in PIT mode before proceeding to
adjust other autopilot pitch axis gains and modes (including ALT and VS modes).
The min/max airspeed fields set the min/max limits of autopilot vertical authority. The autopilot will
limit the pitch control to stay within the min/max airspeed limits.
The vertical speed gain is one of the most important gains in the system since it controls the behavior of
the VNAV, ALT, and VS modes and also largely determines how well the plane flies LPV and ILS
approaches.
The vertical speed gain is adjusted in a very similar manner to the pitch servo gain. Engage the autopilot
in ROL/VS modes in level flight (vertical speed approximately zero).
Adjust the vertical speed gain so the aircraft properly responds to the VS guidance from the flight
director.
1. Overpower the autopilot to fly away from the current flight director commanded vertical speed.
2. Release controls and monitor autopilot response and closure back to the commanded vertical
speed.
3. Set the vertical speed gain higher to make the autopilot more aggressive if it feels “lazy” or not as
responsive as desired.
4. Set the vertical speed gain lower to make the autopilot less aggressive if the control is too “harsh”
or more responsive than desired.
The vertical accel gain can often be left set at 1.00, but can be used to improve altitude captures when
climbing or descending in VS or VNAV mode.
1. Climb to an altitude target in VS mode and note the altitude capture.
2. Set the vertical accel gain higher if the aircraft objectionably overshoots the altitude target before
leveling off at the correct altitude.
3. Set the vertical accel gain lower if the aircraft objectionably undershoots the altitude target before
leveling off at the correct altitude.
Similar to the vertical speed gain and vertical accel gain, the airspeed gain and airspeed accel gain can be
used to improve airspeed hold performance when needed.
The yaw servo has additional advanced and expert settings that can be adjusted to achieve the desired yaw
damping performance. These settings are detailed in Section 30.4.10.10
and should only be adjusted after
studying the description to properly understand their effect on the yaw servo. See preceding note
to access
the advanced/expert settings.
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