Narrative:

I am an a&P mechanic employed by air carrier at ZZZ. My bid location is 'C' check, working in the hangar. Our crew performed a 'segmented C check' on aircraft xyz on the night/morning of nov/thu/00. After maintenance was completed and aircraft had been 'pushed out and leak checked,' I performed the 'post dock inspection' on the aircraft. This inspection includes checking flight control locks are removed, hydraulic quantities, and cockpit circuit breaker, among other items. Apparently, during my check of the cockpit, I overlooked the resetting of the 'standby hydraulic' circuit breaker. This circuit breaker (on our 300/500 aircraft) is located behind and below the first officer's seat. In addition, this circuit breaker (as well as several others) is placed behind a microphone installation on the circuit breaker panel, which obstructs a clear view of the circuit breaker's. From the limited information I've had, an FAA check pilot found the circuit breaker pulled (with a lockout collar on it) during a revenue flight on nov/xx/00. Evidently, this circuit breaker lockout collar didn't have a 'do not operate' tag attached to it, so I assume I missed seeing it during my inspection due to the obstructed view of the panel. The 'standby hydraulic' circuit breaker is normally pulled and collared during the 'pre dock' phase of the check, when our 'functions crew' performs operations checks on various system. I also think that the run-up/leak check mechanic who runs the aft engines should also perform the 'post dock' inspection in the future, since it is also his job to assure all circuit breaker's are reset. In this particular instance, not only myself, but the 'taxi to the gate' mechanic, as well as the pilot (on revenue flight) failed to notice and reset this circuit breaker.

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Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED IN NON COMPLIANCE WITH THE STANDBY RUDDER HYD PUMP CB PULLED AND COLLARED FOR MAINT.

Narrative: I AM AN A&P MECH EMPLOYED BY ACR AT ZZZ. MY BID LOCATION IS 'C' CHK, WORKING IN THE HANGAR. OUR CREW PERFORMED A 'SEGMENTED C CHK' ON ACFT XYZ ON THE NIGHT/MORNING OF NOV/THU/00. AFTER MAINT WAS COMPLETED AND ACFT HAD BEEN 'PUSHED OUT AND LEAK CHKED,' I PERFORMED THE 'POST DOCK INSPECTION' ON THE ACFT. THIS INSPECTION INCLUDES CHKING FLT CTL LOCKS ARE REMOVED, HYD QUANTITIES, AND COCKPIT CB, AMONG OTHER ITEMS. APPARENTLY, DURING MY CHK OF THE COCKPIT, I OVERLOOKED THE RESETTING OF THE 'STANDBY HYD' CB. THIS CB (ON OUR 300/500 ACFT) IS LOCATED BEHIND AND BELOW THE FO'S SEAT. IN ADDITION, THIS CB (AS WELL AS SEVERAL OTHERS) IS PLACED BEHIND A MIKE INSTALLATION ON THE CB PANEL, WHICH OBSTRUCTS A CLR VIEW OF THE CB'S. FROM THE LIMITED INFO I'VE HAD, AN FAA CHK PLT FOUND THE CB PULLED (WITH A LOCKOUT COLLAR ON IT) DURING A REVENUE FLT ON NOV/XX/00. EVIDENTLY, THIS CB LOCKOUT COLLAR DIDN'T HAVE A 'DO NOT OPERATE' TAG ATTACHED TO IT, SO I ASSUME I MISSED SEEING IT DURING MY INSPECTION DUE TO THE OBSTRUCTED VIEW OF THE PANEL. THE 'STANDBY HYD' CB IS NORMALLY PULLED AND COLLARED DURING THE 'PRE DOCK' PHASE OF THE CHK, WHEN OUR 'FUNCTIONS CREW' PERFORMS OPS CHKS ON VARIOUS SYS. I ALSO THINK THAT THE RUN-UP/LEAK CHK MECH WHO RUNS THE AFT ENGS SHOULD ALSO PERFORM THE 'POST DOCK' INSPECTION IN THE FUTURE, SINCE IT IS ALSO HIS JOB TO ASSURE ALL CB'S ARE RESET. IN THIS PARTICULAR INSTANCE, NOT ONLY MYSELF, BUT THE 'TAXI TO THE GATE' MECH, AS WELL AS THE PLT (ON REVENUE FLT) FAILED TO NOTICE AND RESET THIS CB.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.