Originally Posted by
PENKO
Apart from these extreme horror stories, the question of the OP remains. Do recent events merit a change in the APU inop MEL-procedure?
Mine has three main generators, two backups and a RAT: lost a main gen the other night, checklist said start the APU and shortly after the ovens and IFE were back on line; if the APU had failed to start we still had 3 generators so no panic, just a bit of load shedding.
If you had just the two gens, U/S APU, no RAT and one of them failed, it’s likely to be land at nearest suitable due to the next step being battery power, but this is all taken care of in the MEL when dispatching (likely both gens required).
Would a functioning APU have helped much in Korea recently? Their problem was more to do with failing engines and the aircraft position; chances were they still had some hydraulics and standby power. To directly answer the question, no, I don’t think APU serviceability needs to be taken into account any more than it is now, as it’s not guaranteed to start anyway. I would be more likely to question the dispatch of an aircraft if it was hot at destination and ground air was unreliable/unavailable...