B777 flight crew is dispatched with APU inoperative and engine driven generator fails as aircraft is...

Attributes
ACN	772200
Time
Date	200801
Place
Locale Reference	atc facility : zzzz.artcc
State Reference	FO
Altitude	msl single value : 38000
Aircraft 1
Controlling Facilities	artcc : zzzz.artcc tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	B777-200
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Route In Use	enroute : other oceanic
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	772200
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : declared emergency
Supplementary
Problem Areas	Company Aircraft
Primary Problem	Aircraft

Narrative:

About 2 1/2 hours into flight; the left engine generator failed. Aircraft had been dispatched with an inoperative APU; so we were left with 1 generator. Fortunately we were just approaching oceanic airspace and were still in contact with domestic ATC. All applicable checklists were run and a conference call was set up with both maintenance and dispatch to weigh all options. Ultimately; I made the decision (with acquiescence from maintenance and dispatch to return considering the following: the WX was good behind us all the way to and including ZZZ; all other system were running normally. We were still close to multiple; good divert fields and would be all along the coast if we turned around. Flying further with only 1 airport between us and the opposite coast over open water with 1 generator was not an option I deemed prudent and operationally it made more sense to me to get the airplane back to a base where we had both major station maintenance and flight service personnel. We actually entered oceanic airspace and were handed over to oceanic ATC as our analysis and final decisions were being made. We then informed ATC we were declaring an emergency and initiated the return procedure and were cleared back to ZZZ. The rest of the flight was uneventful.

Original NASA ASRS Text

Title: B777 FLT CREW IS DISPATCHED WITH APU INOPERATIVE AND ENGINE DRIVEN GENERATOR FAILS AS ACFT IS ENTERING OCEANIC AIRSPACE. FLT CREW ELECTS TO RETURN TO DEPARTURE ARPT.

Narrative: ABOUT 2 1/2 HRS INTO FLT; THE L ENG GENERATOR FAILED. ACFT HAD BEEN DISPATCHED WITH AN INOP APU; SO WE WERE LEFT WITH 1 GENERATOR. FORTUNATELY WE WERE JUST APCHING OCEANIC AIRSPACE AND WERE STILL IN CONTACT WITH DOMESTIC ATC. ALL APPLICABLE CHKLISTS WERE RUN AND A CONFERENCE CALL WAS SET UP WITH BOTH MAINT AND DISPATCH TO WEIGH ALL OPTIONS. ULTIMATELY; I MADE THE DECISION (WITH ACQUIESCENCE FROM MAINT AND DISPATCH TO RETURN CONSIDERING THE FOLLOWING: THE WX WAS GOOD BEHIND US ALL THE WAY TO AND INCLUDING ZZZ; ALL OTHER SYS WERE RUNNING NORMALLY. WE WERE STILL CLOSE TO MULTIPLE; GOOD DIVERT FIELDS AND WOULD BE ALL ALONG THE COAST IF WE TURNED AROUND. FLYING FURTHER WITH ONLY 1 ARPT BTWN US AND THE OPPOSITE COAST OVER OPEN WATER WITH 1 GENERATOR WAS NOT AN OPTION I DEEMED PRUDENT AND OPERATIONALLY IT MADE MORE SENSE TO ME TO GET THE AIRPLANE BACK TO A BASE WHERE WE HAD BOTH MAJOR STATION MAINT AND FLT SVC PERSONNEL. WE ACTUALLY ENTERED OCEANIC AIRSPACE AND WERE HANDED OVER TO OCEANIC ATC AS OUR ANALYSIS AND FINAL DECISIONS WERE BEING MADE. WE THEN INFORMED ATC WE WERE DECLARING AN EMER AND INITIATED THE RETURN PROC AND WERE CLRED BACK TO ZZZ. THE REST OF THE FLT WAS UNEVENTFUL.

Data retrieved from NASA's ASRS site as of May 2009 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.

B777 flight crew is dispatched with APU inoperative and engine driven generator fails as aircraft is entering oceanic airspace. Flight crew elects to return to departure airport.