Narrative:

I took over an aircraft from one of our crew. The aircraft was carrying an MEL item for an inoperative engine generator. This had been written up and deferred by our maintenance while overnighting at a maintenance base. The outgoing crew stated that the aircraft was operating per the MEL using the APU generator in place of the inoperative engine generator. The write-up in the logbook indicated that it was ok to continue per this MEL and the special procedure which went with the MEL. This procedure was to disconnect the generator from the engine. This can be done from the cockpit and I assume by maintenance in other fashions. The MEL calls for the crew to check the 3 TR's prior to each flight, which was done, and there is a note that the disconnect switch should be pushed prior to each flight in the event that maintenance has attempted to re-attach the generator thereby eliminating the possibility of damage. Of course, no maintenance personnel had been on the airplane that day since it left the base that morning and it had flown 5 or 6 flts prior to my taking over. It was learned the following day that the generator was still attached to the engine. Apparently the maintenance folks did not do the disconnect per the MEL and the previous crew did not either. With the assumptions above, I did not attempt to re-disconnect the generator during my 2 legs that day. Being that our maintenance had done the work and given the aircraft had flown several legs, I made the unfortunate assumption that the special procedure had indeed been done the night before since the logbook said that it was 'ok to continue per the MEL and the special procedure.' and as I said, I saw no need to re-disconnect it, as no maintenance had been done that day. The lesson, of course, is to eliminate the 'assume' word from my vocabulary and check everything/do everything in the MEL -- even if it appears uncalled for due to the circumstances.

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Original NASA ASRS Text

Title: 2 ACR CREW FLEW A B737 WITH AN INTEGRATED DRIVE GENERATOR CONNECTED WHEN THE MEL REQUIRED IT TO BE DISCONNECTED DUE TO A GENERATOR PROB.

Narrative: I TOOK OVER AN ACFT FROM ONE OF OUR CREW. THE ACFT WAS CARRYING AN MEL ITEM FOR AN INOP ENG GENERATOR. THIS HAD BEEN WRITTEN UP AND DEFERRED BY OUR MAINT WHILE OVERNIGHTING AT A MAINT BASE. THE OUTGOING CREW STATED THAT THE ACFT WAS OPERATING PER THE MEL USING THE APU GENERATOR IN PLACE OF THE INOP ENG GENERATOR. THE WRITE-UP IN THE LOGBOOK INDICATED THAT IT WAS OK TO CONTINUE PER THIS MEL AND THE SPECIAL PROC WHICH WENT WITH THE MEL. THIS PROC WAS TO DISCONNECT THE GENERATOR FROM THE ENG. THIS CAN BE DONE FROM THE COCKPIT AND I ASSUME BY MAINT IN OTHER FASHIONS. THE MEL CALLS FOR THE CREW TO CHK THE 3 TR'S PRIOR TO EACH FLT, WHICH WAS DONE, AND THERE IS A NOTE THAT THE DISCONNECT SWITCH SHOULD BE PUSHED PRIOR TO EACH FLT IN THE EVENT THAT MAINT HAS ATTEMPTED TO RE-ATTACH THE GENERATOR THEREBY ELIMINATING THE POSSIBILITY OF DAMAGE. OF COURSE, NO MAINT PERSONNEL HAD BEEN ON THE AIRPLANE THAT DAY SINCE IT LEFT THE BASE THAT MORNING AND IT HAD FLOWN 5 OR 6 FLTS PRIOR TO MY TAKING OVER. IT WAS LEARNED THE FOLLOWING DAY THAT THE GENERATOR WAS STILL ATTACHED TO THE ENG. APPARENTLY THE MAINT FOLKS DID NOT DO THE DISCONNECT PER THE MEL AND THE PREVIOUS CREW DID NOT EITHER. WITH THE ASSUMPTIONS ABOVE, I DID NOT ATTEMPT TO RE-DISCONNECT THE GENERATOR DURING MY 2 LEGS THAT DAY. BEING THAT OUR MAINT HAD DONE THE WORK AND GIVEN THE ACFT HAD FLOWN SEVERAL LEGS, I MADE THE UNFORTUNATE ASSUMPTION THAT THE SPECIAL PROC HAD INDEED BEEN DONE THE NIGHT BEFORE SINCE THE LOGBOOK SAID THAT IT WAS 'OK TO CONTINUE PER THE MEL AND THE SPECIAL PROC.' AND AS I SAID, I SAW NO NEED TO RE-DISCONNECT IT, AS NO MAINT HAD BEEN DONE THAT DAY. THE LESSON, OF COURSE, IS TO ELIMINATE THE 'ASSUME' WORD FROM MY VOCABULARY AND CHK EVERYTHING/DO EVERYTHING IN THE MEL -- EVEN IF IT APPEARS UNCALLED FOR DUE TO THE CIRCUMSTANCES.

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.