TM 55-1510-221-CL
AC/DC POWER
CHECK FOR:
1. AC frequency - 394 to 406 Hz.
2.
AC voltage - 104 to 124 VAC.
3.
DC load - Check.
4.
DC voltage - 27.0 to 28.5 VDC.
AUTOMATIC FLIGHT CONTROL SYSTEM
NOTE
Pause a few seconds between each step to allow time for the proper indications.
1.
Set alert controller more than 1000 feet above altitude indicated on pilot's altimeter. The pilot's altimeter alert
light should be extinguished.
2.
Decrease the alert controller to within 1000 feet of the pilot's altimeter setting. The alert light should illuminate.
3.
Decrease the controller to less the 250 feet above the pilot's altimeter setting. The alert light should extinguish.
4.
Increase the controller to 300 (50 feet above the pilot's altimeter indication) and check that the alert light
illuminates.
5.
Set the desired altitude.
6.
Autopilot controller UP TRIM, DN TRIM annunciators CHECK not illuminated.
CAUTION
A steady illumination of UP TRIM or DN TRIM annunciator indicates that the automatic
synchronization is not functioning and the autopilot should not be engaged.
7.
Turn knob - Center.
C2 P-5
