TM 1-1510-225-10
3A-20
1. Autopilot Engage/Disengage Push-button Selector Switch
2. Autopilot Engaged Annunciator
3. Half Bank Mode Annunciator
4. Half Bank Mode Push -button Selector Switch
5. Autopilot Left/Right System Transfer Indicator
6. Autopilot Left/Right Transfer Push-button Selector Switch
7. Roll/Roll Rate Command Control Knob
8. Vertical Trim Thumbwheel Control
9. Pilot/Copilot Roll, Pitch, and Yaw Axis Failure Annunciators
10. Soft Ride Mode Annunciator
11. Soft Ride Mode Push -button Selector Switch
12. Yaw Damper Engage/Disengage Push-button Selector Switch
13. Yaw Damper Engaged Annunciator
Figure 3A-8. Autopilot Controller
Roll rate commands increase in direct proportion
to the degree of roll attitude control knob deflection, up
to the flight control system's maximum commandable
roll rate or attitude. Releasing the knob allows it to
return automatically to its center position. The flight
director will command the aircraft to maintain the
existing roll attitude. Roll attitudes of less than 2° of
bank angle will revert to wings-level flight.
(h) Vertical Trim Thumb wheel Control.
The vertical trim thumbwheel control, placarded DN
and UP, is a three position, return to center rocker
switch. Calibration of the control varies, depending on
the flight director mode engaged and whether the flight
crew activates the vertical trim switch momentarily,
allowing it to return to center immediately upon feeling
it click (discrete trim), or holds the switch in position for
several seconds (continuous trim).
Pressing the upper portion of the rocker switch
adjusts the aircraft's pitch attitude downward, and
pressing the lower portion adjusts the attitude upward.
Activating vertical trim cancels certain flight
director vertical tracking modes, but has no effect on
modes engaged in the arm phase. The flight director
will revert to pitch attitude hold if it was coupled in
glideslope, VNAV, climb, altitude capture, or go-
around at the moment of trim activation. If the descent
mode was coupled, the flight director will revert to
vertical speed hold and will remain coupled throughout
vertical trim operation.
If using continuous vertical trim when the capture
point is reached, the capture will occur and vertical
trim will be ignored until released. After release,
further use of vertical trim will cause the same effect
as described above. The effect of activating discrete
or continuous trim on flight director operations is
shown in Table 3A-1.
