Electric elevator trim

TM 1-1510-223-MTF

PROCEDURE

TROUBLESHOOTING

REFERENCE

If the SBY annunciator on the flight director mode selector

does not illuminate within 10 seconds after the avionics

master switch is turned on, the autopilot has failed self-test

and is considered inoperative and should not be used. Do not

force the elevator trim system beyond the limits which are

indicated on the ELEVATOR trim tab indicator.

m. Electric elevator trim - Check.

(1) ELEV TRIM switch - On.

(2) Pilot and copilot trim switches

- Check operation.

Operation of the electric trim system should occur only by

movement of pairs of switches. Any movement of the elevator

trim wheel while depressing only one switch element indicates

a trim system malfunction. Turn the electric elevator trim

control switch OFF and conduct flight by operating the

elevator trim wheel manually. Do not use autopilot.

(3) Pilot and copilot. Check individual element

for no movement of trim, then check proper

operation of both elements.

(4) Check pilot switches

override

copilot

switches while trim-

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