Narrative:

#2 engine generator/integral drive was MEL inoperative. However, generator operating normally on departure. At top of climb, low oil pressure light for the #2 idg began flickering. After checking the voltage/frequency normal. We decided to watch it. Within 5-10 mins, the light was on steady, and voltage/frequency of #2 generator began fluctuating. Decision made to disconnect #2 idg unit. We were unable to disconnect the idg/generator unit. As all indications were that the unit was indeed failing, I decided to return to sfo, and shut down the #2 engine to prevent destruction of the idg unit. We didn't feel lucky enough to fly all the way to hnl on 2 engines! Shutdown was approximately 50 mins after departure from sfo, flight was a scheduled trip, airlines flight sfo-hnl. The idg should have been disconnected prior to departure when starting engine #2, and noticing the generator operating, we should have attempted the disconnect then it would have saved thousands of dollars, lots of embarrassment, and much bad feelings on the part of our passengers!

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Original NASA ASRS Text

Title: ACR WDB FLC ATTEMPTED TO USE AN ENG GENERATOR THAT HAD BEEN WRITTEN UP AS INOP. GENERATOR DRIVE FAILED AGAIN AFTER TKOF AND WHEN FLC COULD DISCONNECT THE DRIVE THEY HAD TO RETURN TO SFO.

Narrative: #2 ENG GENERATOR/INTEGRAL DRIVE WAS MEL INOP. HOWEVER, GENERATOR OPERATING NORMALLY ON DEP. AT TOP OF CLB, LOW OIL PRESSURE LIGHT FOR THE #2 IDG BEGAN FLICKERING. AFTER CHKING THE VOLTAGE/FREQ NORMAL. WE DECIDED TO WATCH IT. WITHIN 5-10 MINS, THE LIGHT WAS ON STEADY, AND VOLTAGE/FREQ OF #2 GENERATOR BEGAN FLUCTUATING. DECISION MADE TO DISCONNECT #2 IDG UNIT. WE WERE UNABLE TO DISCONNECT THE IDG/GENERATOR UNIT. AS ALL INDICATIONS WERE THAT THE UNIT WAS INDEED FAILING, I DECIDED TO RETURN TO SFO, AND SHUT DOWN THE #2 ENG TO PREVENT DESTRUCTION OF THE IDG UNIT. WE DIDN'T FEEL LUCKY ENOUGH TO FLY ALL THE WAY TO HNL ON 2 ENGS! SHUTDOWN WAS APPROX 50 MINS AFTER DEP FROM SFO, FLT WAS A SCHEDULED TRIP, AIRLINES FLT SFO-HNL. THE IDG SHOULD HAVE BEEN DISCONNECTED PRIOR TO DEP WHEN STARTING ENG #2, AND NOTICING THE GENERATOR OPERATING, WE SHOULD HAVE ATTEMPTED THE DISCONNECT THEN IT WOULD HAVE SAVED THOUSANDS OF DOLLARS, LOTS OF EMBARRASSMENT, AND MUCH BAD FEELINGS ON THE PART OF OUR PAXS!

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.