TruTrak ADI Pilot II - Manual (Page 9)

TruTrak Flight Systems ADI Pilot I & II Autopilot Installation Manual
December 2009 7 8300-012 Rev B
While the autopilot is in its disengaged (off) mode, press and hold the lower right knob. The display will now show “–| – |–”
with the center dash character blinking, indicating the Manual Gyro Set operation. Continue to hold the knob in for a few
seconds while the autopilot is not being moved about, to re-center the gyro manually.
Must be performed before first flight
The next step in the check-out procedure is to verify that the servos run, and in the correct direction. Press and release the
lower right knob to again engage the roll axis of the autopilot. The roll servo should be responding at this time, moving the
controls only very slowly in attempt to hold bank angle constant. Rotate the lower right knob to the right and select a bank
angle of approximately 20 degrees to the right. The autopilot will now move the controls in an attempt to cause a turn towards
the right. If servo direction is not correct, the wires going to pins 4 and 5 of the roll servo (pins 20 and 21 on the main
connector) must be reversed to achieve the correct response. If the servo does not move at all, double-check the torque setting
(setup screen 2) to make sure it is at least 10. If a servo jitters but does not actually rotate, check the wiring on the four servo
drive lines to that servo for continuity and correctness. If the servo does not seem to have any torque, check the roll torque
control line for continuity and correctness. With a torque setting of 12, and the autopilot engaged, the torque control line (pin 6
at servo) should measure approximately 4.9 volts DC.
Rotate the lower right knob to the left and select a bank angle of approximately 20 degrees to the left. The autopilot will now
move the controls in attempt to cause a turn to the left. Rotate the lower right knob to the right and select a bank angle of zero
to stop the roll servo.
Similarly to the roll servo checkout, push and release the lower left knob to engage the pitch axis. The pitch servo should be
responding at this time, moving the controls only very slightly in attempt to hold the selected altitude. Push and hold the lower
left knob in and rotate to the right. This is the altitude adjust feature, select 90. This is a climb of 90 feet. The pitch servo
should now move the controls in an attempt to cause the aircraft to climb. If servo direction is not correct, the jumper between
pins 1 & 2 on J101 (the 25 pin connector), will either need to be added or cut. If the servo does not move at all, double-check
the torque setting (setup screen 2) to make sure it is at least 10. If a servo jitters but does not actually rotate, check the wiring
on the four servo drive lines to that servo for continuity and correctness. If the servo does not seem to have any torque, check
the roll torque control line for continuity and correctness. With a torque setting of 12, and the autopilot engaged, the torque
control line should measure approximately 4.9 volts DC.
Push and hold the lower left knob again and rotate to the left, and select -90. Now the servo will stop moving. Push and hold
the lower left knob again and rotate to the left, and select -90. Now the servo will move the controls in an attempt to cause the
aircraft to descend. Push and hold the lower left knob again, and select zero to stop the pitch servo.
While each servo is running, check that the servo arm or capstan is properly operating the controls. For servo installations
using an arm, check that as the controls go from limit to limit, the arm of the servo remains in the operating range of the servo
(a maximum of 100 degrees total rotation) and that when the controls are centered, the connecting push rod is approximately
perpendicular to the arm of the servo. For capstan systems, insure that the cabling remains at proper tension and is properly
secured as the servo moves the controls from stop to stop. Insure that the servo remains secure in its mounting and does not
flex its mounting bracket as it drives the control to its stops. For installations using an arm, insure that as the servo moves the
control towards the end of control travel it does not cause the main control’s torque tube to flex in any way that could cause
control system lockup at the extremes of servo travel. Insure that any “lost motion” in the linkages is eliminated or minimized,
in order to maximize the performance of the autopilot. Lost motion (dead zone) will result in wandering or slow “hunting”
behavior in flight. Lost motion in the linkage can best be observed by temporarily clamping the servo arm and gently moving
an aileron or the elevator back and forth, while observing how much aileron or elevator movement takes place against the
clamped servo.
The next step in the check-out procedure is to verify that the serial input from the GPS receiver is being properly received and
interpreted. With the aircraft outside of any building, power up the GPS receiver and the autopilot. After the GPS receiver
acquires its position, the autopilot display will change from “– – –” to “OFF” indicating that valid position data is available. If
the word “OFF” is not displayed, even after it is known that the GPS unit has a position fix, the problem must be diagnosed.
Summary:
ENGAGE AUTOPILOT WITH FLIGHT CONTROL CENTERED,
ROTATE KNOB CLOCKWISE. FLIGHT CONTROL MUST MOVE