h. Faulty remote-controlled circuit breaker
i. Defective landing gear control switch.
j. Defective wiring.
Landing gear fails to retract.
a. Safety switch not closing.
b. Pressure switch not closing.
c. Gear selector valve stuck.
d. Circuit is open between the selector valve
and the power relay.
e. Time delay circuit opening prematurely.
f. Hand pump handle improperly stowed.
g. Service valve in up position.
h. Defective landing gear control switch.
i. Defective wiring.
Landing gear fails to extend.
a. Service valve switches faulty.
b. Landing gear selector valve stuck in up posi-
c. Control switch not providing power to the
extend side of selector valve.
d. Defective limit switch.
e. Defective landing gear control switch.
Landing gear pump motor continues to run after
the gear is retracted, causing the circuit breaker
a. Pressure switch not opening on high pres-
b. Low accumulator charge.
c. Excessive fluid leakage past the piston seals
in the actuators.
d. Defective valve in the power pack.