Narrative:

I was assigned to aircraft to finish a maintenance check and some minor details after a major repair to the fuse cage. Repair was just aft of forward cargo bin. The aircraft was ferried in for repair due to fuselage puncture. The repair had been signed off and the aircraft was restored to normal confign when I arrived on my shift. I was working with my lead mechanic. I was given the task of resealing the forward cargo door threshold after a leak had been previously found. It was also brought to my attention that there was an open logbook item but all paperwork for the repair was closed and completed. The logbook write-up said that the 'S00813; altitude pressure switch disconnected at S23.' S23 is a stringer location in structure term and was confusing and misleading. After my lead researched the write-up and location; it was thought to be an error and was determined to be circuit breakers in the oxygen system that was still open after cockpit inspection. I was directed to reset the breakers and pressurize the aircraft to leak inspect the cargo area again. My lead and I also contacted maintenance control to clarify the criteria to ferry a flight unpressurized and they only mentioned circuit breakers. B/C check called me and told me that after a routine mask drop inspection failed; it was discovered that the altitude pressure switch was disconnected in the J23 junction box! The original write-up was incorrect and misleading.

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Original NASA ASRS Text

Title: AFTER A MAJOR REPAIR FOR EXTERNAL FUSELAGE SKIN PUNCTURE ON A B737-700 AN OPEN LOGBOOK ITEM WAS FOUND STATING 'ALTERNATE PRESS SWITCH DISCONNECTED AT STRINGER S-23.' ACTUAL LOCATION WAS J-23 JUNCTION BOX.

Narrative: I WAS ASSIGNED TO ACFT TO FINISH A MAINT CHK AND SOME MINOR DETAILS AFTER A MAJOR REPAIR TO THE FUSE CAGE. REPAIR WAS JUST AFT OF FORWARD CARGO BIN. THE ACFT WAS FERRIED IN FOR REPAIR DUE TO FUSELAGE PUNCTURE. THE REPAIR HAD BEEN SIGNED OFF AND THE ACFT WAS RESTORED TO NORMAL CONFIGN WHEN I ARRIVED ON MY SHIFT. I WAS WORKING WITH MY LEAD MECH. I WAS GIVEN THE TASK OF RESEALING THE FORWARD CARGO DOOR THRESHOLD AFTER A LEAK HAD BEEN PREVIOUSLY FOUND. IT WAS ALSO BROUGHT TO MY ATTN THAT THERE WAS AN OPEN LOGBOOK ITEM BUT ALL PAPERWORK FOR THE REPAIR WAS CLOSED AND COMPLETED. THE LOGBOOK WRITE-UP SAID THAT THE 'S00813; ALT PRESSURE SWITCH DISCONNECTED AT S23.' S23 IS A STRINGER LOCATION IN STRUCTURE TERM AND WAS CONFUSING AND MISLEADING. AFTER MY LEAD RESEARCHED THE WRITE-UP AND LOCATION; IT WAS THOUGHT TO BE AN ERROR AND WAS DETERMINED TO BE CIRCUIT BREAKERS IN THE OXYGEN SYS THAT WAS STILL OPEN AFTER COCKPIT INSPECTION. I WAS DIRECTED TO RESET THE BREAKERS AND PRESSURIZE THE ACFT TO LEAK INSPECT THE CARGO AREA AGAIN. MY LEAD AND I ALSO CONTACTED MAINT CTL TO CLARIFY THE CRITERIA TO FERRY A FLT UNPRESSURIZED AND THEY ONLY MENTIONED CIRCUIT BREAKERS. B/C CHK CALLED ME AND TOLD ME THAT AFTER A ROUTINE MASK DROP INSPECTION FAILED; IT WAS DISCOVERED THAT THE ALT PRESSURE SWITCH WAS DISCONNECTED IN THE J23 JUNCTION BOX! THE ORIGINAL WRITE-UP WAS INCORRECT AND MISLEADING.

Data retrieved from NASA's ASRS site as of May 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.