Narrative:

While accomplishing multiple maintenance tasks on air carrier aircraft xyz, the flight crew reported a left 'wing to body' overheat condition. Through deductive troubleshooting I concluded that the APU bleed air (prior to the load control valve) was the cause of this overheat, thus rendering the APU inoperative. I asked the lead mechanic on shift to contact the 'maintenance operations center' for MEL authority/authorized for both the APU and the autoland portion of the autoplt while I finished troubleshooting a previous discrepancy regarding the right air data system and then retrieved an external aircart used to start the engines when the APU is inoperative. When I returned to the jetway the lead mechanic provided me with all the necessary information to release the aircraft for flight under MEL provisions xx-Y and zz-X. I completed all the necessary logbook entries, closed the main cabin door, started the engines and dispatched the aircraft for flight. Several days later while researching the computer entries (electronic logbook) to see what corrective action was taken to repair the 'wing to body' discrepancy I discovered that I had neglected to document or accomplish the special procedures required to dispatch an aircraft under MEL xx-Y which is to open and collar the breaker on the APU accessory unit on the E3-3 shelf.

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Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED IN NON COMPLIANCE WITH THE APU DEFERRED AS INOP BUT THE SPECIAL PROC FOR THE CIRCUIT BREAKER LOCK WAS NOT ACCOMPLISHED.

Narrative: WHILE ACCOMPLISHING MULTIPLE MAINT TASKS ON ACR ACFT XYZ, THE FLC RPTED A L 'WING TO BODY' OVERHEAT CONDITION. THROUGH DEDUCTIVE TROUBLESHOOTING I CONCLUDED THAT THE APU BLEED AIR (PRIOR TO THE LOAD CTL VALVE) WAS THE CAUSE OF THIS OVERHEAT, THUS RENDERING THE APU INOP. I ASKED THE LEAD MECH ON SHIFT TO CONTACT THE 'MAINT OPS CTR' FOR MEL AUTH FOR BOTH THE APU AND THE AUTOLAND PORTION OF THE AUTOPLT WHILE I FINISHED TROUBLESHOOTING A PREVIOUS DISCREPANCY REGARDING THE R AIR DATA SYS AND THEN RETRIEVED AN EXTERNAL AIRCART USED TO START THE ENGS WHEN THE APU IS INOP. WHEN I RETURNED TO THE JETWAY THE LEAD MECH PROVIDED ME WITH ALL THE NECESSARY INFO TO RELEASE THE ACFT FOR FLT UNDER MEL PROVISIONS XX-Y AND ZZ-X. I COMPLETED ALL THE NECESSARY LOGBOOK ENTRIES, CLOSED THE MAIN CABIN DOOR, STARTED THE ENGS AND DISPATCHED THE ACFT FOR FLT. SEVERAL DAYS LATER WHILE RESEARCHING THE COMPUTER ENTRIES (ELECTRONIC LOGBOOK) TO SEE WHAT CORRECTIVE ACTION WAS TAKEN TO REPAIR THE 'WING TO BODY' DISCREPANCY I DISCOVERED THAT I HAD NEGLECTED TO DOCUMENT OR ACCOMPLISH THE SPECIAL PROCS REQUIRED TO DISPATCH AN ACFT UNDER MEL XX-Y WHICH IS TO OPEN AND COLLAR THE BREAKER ON THE APU ACCESSORY UNIT ON THE E3-3 SHELF.

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.