Narrative:

I was the non-flying pilot. We were at FL320 in cruise in an aircraft dispatched with an inoperative APU. We got intermittent electrical failures off and on for a few seconds and then noticed that the right CSD oil temp was pegged and we had a right CSD low oil pressure light on. We ran the checklist from the QRH and disconnected the right CSD; which meant that we were down to the remaining generator on the left engine. We didn't declare an emergency because it was good VMC weather but did request a 180 turn back to our departure airport; which was the best and the closest available. We landed within 30 minutes with no further system degradation. After a later review of the flight manual references to 'conditions requiring an emergency declaration' we realized that it might have been a better practice to have declared an emergency due to its reference to a '...failure...of an aircraft system which compromises safe operation.' we should always err on the safe side and declare an emergency when these smaller issues happen; incase they end up turning into something greater.

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Original NASA ASRS Text

Title: Dispatched with an inoperative APU the flight crew of an MD80 returned to their departure aiport shortly after reaching cruise when the right CSD had to be disconnected due to high oil temperature and low pressure.

Narrative: I was the non-flying pilot. We were at FL320 in cruise in an aircraft dispatched with an inoperative APU. We got intermittent electrical failures off and on for a few seconds and then noticed that the right CSD oil temp was pegged and we had a right CSD low oil pressure light on. We ran the checklist from the QRH and disconnected the right CSD; which meant that we were down to the remaining generator on the left engine. We didn't declare an emergency because it was good VMC weather but did request a 180 turn back to our departure airport; which was the best and the closest available. We landed within 30 minutes with no further system degradation. After a later review of the flight manual references to 'conditions requiring an emergency declaration' we realized that it might have been a better practice to have declared an emergency due to its reference to a '...failure...of an aircraft system which compromises safe operation.' We should always err on the safe side and declare an emergency when these smaller issues happen; incase they end up turning into something greater.

Data retrieved from NASA's ASRS site as of July 2013 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.