What was found
(CAN) MOTOR WOULD RUN AS DESIGNED BUT BECAUSE OF ONE BAD COMUTATOR SEGMENT WOULD NOT TURN WHEN SELECTED IF BRUSH WAS ON BAD SEGMENT. DURING FLT AS HYD PRESS IS LOWERED (DUE TO TEMP) PUMP WILL COME ON FOR 1-2 SECONDS TO BUILD UP FROM 2,750 PSI TO 3,000 AND SHUT OFF. A SAFETY MACHINE IS BUILT IN IF AFTER POWER IS SELECTED TO 15 SECONDS - 02 AMP BREAKER WILL POP AND SHUT OFF SYS - NORMAL GEAR EXT OR RETRACTION IS 8 SECONDS. 1ST TIME AFTER ONE ONE- HALF HRS OF FLT - C/B TRIPPED AND GEAR PUMPED DOWN BY HAND. ACFT PLACED ON JACK, NORMAL, PRESSURE SWITCH CHANGED AS IT WAS FELT TO BE INTERMITENT 2ND TIME IT HAPPENED - GEAR PUMPED DOWN AGAIN AND REMAINED FAILED. POWER PAK REPLACED. (X)