Narrative:

Aircraft was scheduled to have the fwd cargo loader system permanently removed and control wire removed from its connector and tied back. Power was removed from aircraft and wire stowed per instructions. Aircraft experienced an over-wing door warning when throttles advanced for takeoff. Aircraft returned to gate for repairs. It was discovered that the wrong wire had been removed from connector and tied back. I performed the described maintenance and thought I had removed the correct wire. The connector was approximately 2 inches in diameter and had approximately 60-65 pins. Wire removed was one row over from correct position. Other factors: 1) workloads were heavy. 2) connector had no individual contact identification 3) paperwork had no check out/test procedures. First and foremost; I should have retained better situational awareness and cross checked the task due to no obvious problem would be known until aircraft was in service; and a lack of clear wire identification existed. Indirectly; the workloads now required on major air carrier maintenance technicians are increasingly due to company personnel 'cutbacks.' example -- my work group has had half of our work complement furloughed and we still retain the same amount of work. The night of the incident; I was trying to complete my assignment so that I could assist a fellow technician who had a 'heavy' workload on a late arring aircraft assigned to himself. However; it is the technician's responsibility to take the proper time and follow the proper procedures in completing the task.callback conversation with reporter revealed the following information: reporter stated the deactivation of the forward cargo loading system was performed with an engineering order job card. The steps were as follows: disconnect the wiring from the loading system circuit breaker and tie back wiring. Gain access to connector XXX and disconnect wire from socket xy and tie back wire. The 65-pin connector does not have numbers on the internal insulation but identifies the pin by enclosing every tenth pin with semi circles. The job card had no functional check to determine the circuit was deactivated correctly. The sequence of steps should have been to gain access to connector XXX and remove the wire at pin xy and tie back. Then reset the system circuit breaker to activate the system to determine the correct wire was removed and tied back. After test of removed wire; then deactivate the circuit breaker. This sequence of steps would have precluded the aircraft maintenance discrepancy.

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Original NASA ASRS Text

Title: A B737-800 HAD THE FORWARD CARGO LOADING SYSTEM DEACTIVATED PER AN ENGINEERING ORDER; BUT WHEN THROTTLES ADVANCED FOR TKOF; THE FLT CREW GOT OVERWING DOOR WARNING. ENGINEERING JOB ORDER IMPLICATED IN INCIDENT.

Narrative: ACFT WAS SCHEDULED TO HAVE THE FWD CARGO LOADER SYSTEM PERMANENTLY REMOVED AND CTL WIRE REMOVED FROM ITS CONNECTOR AND TIED BACK. POWER WAS REMOVED FROM ACFT AND WIRE STOWED PER INSTRUCTIONS. ACFT EXPERIENCED AN OVER-WING DOOR WARNING WHEN THROTTLES ADVANCED FOR TKOF. ACFT RETURNED TO GATE FOR REPAIRS. IT WAS DISCOVERED THAT THE WRONG WIRE HAD BEEN REMOVED FROM CONNECTOR AND TIED BACK. I PERFORMED THE DESCRIBED MAINT AND THOUGHT I HAD REMOVED THE CORRECT WIRE. THE CONNECTOR WAS APPROX 2 INCHES IN DIAMETER AND HAD APPROX 60-65 PINS. WIRE REMOVED WAS ONE ROW OVER FROM CORRECT POSITION. OTHER FACTORS: 1) WORKLOADS WERE HVY. 2) CONNECTOR HAD NO INDIVIDUAL CONTACT IDENTIFICATION 3) PAPERWORK HAD NO CHECK OUT/TEST PROCS. FIRST AND FOREMOST; I SHOULD HAVE RETAINED BETTER SITUATIONAL AWARENESS AND CROSS CHKED THE TASK DUE TO NO OBVIOUS PROB WOULD BE KNOWN UNTIL ACFT WAS IN SVC; AND A LACK OF CLEAR WIRE IDENTIFICATION EXISTED. INDIRECTLY; THE WORKLOADS NOW REQUIRED ON MAJOR AIR CARRIER MAINT TECHNICIANS ARE INCREASINGLY DUE TO COMPANY PERSONNEL 'CUTBACKS.' EXAMPLE -- MY WORK GROUP HAS HAD HALF OF OUR WORK COMPLEMENT FURLOUGHED AND WE STILL RETAIN THE SAME AMOUNT OF WORK. THE NIGHT OF THE INCIDENT; I WAS TRYING TO COMPLETE MY ASSIGNMENT SO THAT I COULD ASSIST A FELLOW TECHNICIAN WHO HAD A 'HVY' WORKLOAD ON A LATE ARRING ACFT ASSIGNED TO HIMSELF. HOWEVER; IT IS THE TECHNICIAN'S RESPONSIBILITY TO TAKE THE PROPER TIME AND FOLLOW THE PROPER PROCS IN COMPLETING THE TASK.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THE DEACTIVATION OF THE FORWARD CARGO LOADING SYSTEM WAS PERFORMED WITH AN ENGINEERING ORDER JOB CARD. THE STEPS WERE AS FOLLOWS: DISCONNECT THE WIRING FROM THE LOADING SYSTEM CIRCUIT BREAKER AND TIE BACK WIRING. GAIN ACCESS TO CONNECTOR XXX AND DISCONNECT WIRE FROM SOCKET XY AND TIE BACK WIRE. THE 65-PIN CONNECTOR DOES NOT HAVE NUMBERS ON THE INTERNAL INSULATION BUT IDENTIFIES THE PIN BY ENCLOSING EVERY TENTH PIN WITH SEMI CIRCLES. THE JOB CARD HAD NO FUNCTIONAL CHK TO DETERMINE THE CIRCUIT WAS DEACTIVATED CORRECTLY. THE SEQUENCE OF STEPS SHOULD HAVE BEEN TO GAIN ACCESS TO CONNECTOR XXX AND REMOVE THE WIRE AT PIN XY AND TIE BACK. THEN RESET THE SYSTEM CIRCUIT BREAKER TO ACTIVATE THE SYSTEM TO DETERMINE THE CORRECT WIRE WAS REMOVED AND TIED BACK. AFTER TEST OF REMOVED WIRE; THEN DEACTIVATE THE CIRCUIT BREAKER. THIS SEQUENCE OF STEPS WOULD HAVE PRECLUDED THE ACFT MAINT DISCREPANCY.

Data retrieved from NASA's ASRS site as of January 2009 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.