TM 55-1510-220-MTF
a.
Up limit switch out of adjustment.
b.
Defective up limit switch.
C28.
Landing gear fails to retract.
a.
Safety switch not closing.
b.
Up limit switch stuck.
C29.
Landing gear fails to retract completely but gear handle light goes out.
a.
Up limit switch operates early.
C30.
Positive down locks do not fully engage.
a.
Down limit switch opens early.
C31.
Landing gear motor fails to shut off when gear extended.
a.
Down limit switch out of adjustment.
b.
Defective down limit switch.
C32.
Flaps fail to extend or retract.
a.
Tripped circuit breaker.
b.
Defective flap motor.
c.
Defective flap control switch.
d.
Defective mechanical component in actuator system.
e.
Defective wiring.
C33.
Flap position indicator inoperative.
a.
Tripped circuit breaker.
b.
Defective position indicator.
c.
Defective position transmitter.
d.
Defective wiring.
C34.
Pitot tube heater fails to operate.
a.
Tripped circuit breaker.
b.
Defective heater.
c.
Defective wiring.
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