Narrative:

Level at FL340 enroute we got a pack left EICAS. Completed the checklist and did not regain the pack. The captain called dispatch on the satcom to discuss ETOPS crossing limitations and ramifications and gave me the aircraft and radios as PF. Due to turbulence at FL340 and an oceanic crossing clearance at FL380; I asked for and received clearance to climb to FL380. At FL360 we got a bleed right EICAS and other associated right bleed system EICAS. We completed all checklist procedures. The cabin pressure started climbing; peaking at around 6900 ft. I immediately notified ATC and requested a turn back and an immediate descent to 10000 ft MSL. The captain and dispatcher agreed that the departure airport would be our diversion airport. We never exceeded cabin limits and the cabin masks did not deploy. We flew an uneventful 22K pounds overweight landing as we did not see a reason to dump fuel for such a small overweight overage. We did run the overweight landing unannunciated checklist. Maintenance determined that a gasket in the right bleed piping had ruptured causing the right bleed system to automatically shutdown. One other note was that we departed with an MEL on the wing anti-ice system. There was a procedure to be able to use wing anti-ice with an MEL checklist. We picked up about ¼ inch of ice on the windshield wiper nuts in the descent with an associated wing ice EICAS but there was nothing we could do about it due to the pack left and bleed right malfunctions we were handling which negated the steps required in the MEL procedure. Another note is I believe that the left pack had a history of overheating and pack trips.

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Original NASA ASRS Text

Title: B777 crew described a sequence of events when the PACK L trip would not reset followed by the BLEED R EICAS due to a bleed duct gasket failure. An expeditious descent was begun while returning to the departure airport.

Narrative: Level at FL340 enroute we got a PACK L EICAS. Completed the checklist and did not regain the pack. The Captain called Dispatch on the SATCOM to discuss ETOPS crossing limitations and ramifications and gave me the aircraft and radios as PF. Due to turbulence at FL340 and an oceanic crossing clearance at FL380; I asked for and received clearance to climb to FL380. At FL360 we got a BLEED R EICAS and other associated right bleed system EICAS. We completed all checklist procedures. The cabin pressure started climbing; peaking at around 6900 ft. I immediately notified ATC and requested a turn back and an immediate descent to 10000 ft MSL. The Captain and Dispatcher agreed that the departure airport would be our diversion airport. We never exceeded cabin limits and the cabin masks did not deploy. We flew an uneventful 22K pounds overweight landing as we did not see a reason to dump fuel for such a small overweight overage. We did run the Overweight Landing Unannunciated checklist. Maintenance determined that a gasket in the right bleed piping had ruptured causing the right bleed system to automatically shutdown. One other note was that we departed with an MEL on the wing anti-ice system. There was a procedure to be able to use wing anti-ice with an MEL checklist. We picked up about ¼ inch of ice on the windshield wiper nuts in the descent with an associated WING ICE EICAS but there was nothing we could do about it due to the PACK L and BLEED R malfunctions we were handling which negated the steps required in the MEL procedure. Another note is I believe that the left pack had a history of overheating and pack trips.

Data retrieved from NASA's ASRS site 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.