B777-200
Flight Crew Last 90 Days 180; Flight Crew Total 11000; Flight Crew Type 7200
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Landed As Precaution; Flight Crew Returned To Departure Airport; General Declared Emergency
Aircraft
The aircraft had a previous write-up regarding fumes and the cabin printer at Door 2L had been replaced.  The planned route to RJAA was 180 minutes ETOPS; pretty far south; crossing 40N140W 41N150W 42N160W 43N170W 42N180E 40N170E.  Event began at FL350 cruise about 2 hours into the flight. During a restroom break for the flying pilots the Captain went out and the Flight Attendant who came into the cockpit engaged me in conversation.  The conversation topics varied; then with no concern expressed; he told me about the strong smell near Door 2L during pre-flight boarding which he thought had been coming from the jetway.  He had not noticed the smell in flight.  The Captain returned shortly and we discussed the Flight Attendant's comments; and as I also needed a restroom break; [I] offered to go by the Door 2L to see if the smell was still there.  While standing in front of Door 2L nothing was noticeable; but standing facing the inflight entertainment workstation 'kiosk' I could smell hot/burning plastic.  I opened the twin small doors (about 4'x7' each) and could see the previously replaced cabin printer.  With the doors open; the smell was pretty strong; but no smoke.  Nothing was hot to the touch; the printer itself was very warm; and the back of the IFE and other switches were warm.  I reported to the Captain via intercom; and then woke the augmenting pilot from his rest seat; asking him to check the area also.  Our augmenting pilot; along with our deadhead Captain; went to investigate further while I returned to the cockpit.  The augmenting pilot called to the Captain and said they smelled the same fumes from the printer area; the printer seemed unusually warm; and [they] had turned off what they believed to be the printer power.  The Captain by now was involved in a SATVOICE call to Dispatch and Maintenance.  We began to work through the Fumes Irregular checklist; including turning off inflight entertainment (IFE) power and seat power outlets; both switches being located at the Door 2L IFE kiosk; as well as recirculation fans and gasper fans.  We were still flying directly away from our nearest suitable airport [the departure airport] and no other airport coming into range for quite a bit of time.  The augmenting pilot informed us the printer not quite as warm as before; the fumes were still present; but the fumes seemed less strong. The augmenting pilot returned to the cockpit as we discussed our options with Dispatch.  Although the condition seemed that it may be resolving; we were left with the fact that there was a previous maintenance repair that was unsuccessful; the smell was still there; plus every 1 minute down track was 2 minutes further from landing.  The Captain decided to return to [departure airport] and informed Dispatch. We began with a FMC ROUTES page offset of 15nm right; sent an ADS emergency message; and made a PAN PAN call on guard for our PACOTS Track-E traffic. As the offset progressed we changed altitude from FL350 to FL345; executed DIVERT [departure airport] via the FMC ALTERNATES page; and completed the turn to [departure airport].  During all this we received a response 'CONFIRM' to our ADS emergency.  I initially replied with ADS text requesting direct [departure airport] and CPDLC ROUTE request.  Our augmenting pilot quickly pointed out we could call [Center] OCEANIC via SATVOICE.  The call was made; and we were able to clarify with ATC our current position; altitude and track.  I inquired if ATC needed any intermediate waypoints; but our clearance remained direct [departure airport] with block FL340-350.  Several aircraft responded to our 'PAN PAN' call via VHF radio.  Position reporting along our 2-1/2 hour return was not quite as expected.  Although we had installed FMC LEGS page crossing at 140W (4045N140W) and 130W (3920N130W); they did not automatically report to Company; and we had little confidence they were CPDLC reporting to ATC.  One minute after the 140W waypoint; we noted the POS page had not reported; so we used the send prompt at POS REPORT 6R.  We also sent a CPDLC POSITION report at this time.  A couple of minutes later; Dispatch requested our 140W report. We finally sent via COMPANY-COM DISPATCH free text.
B777-200 First Officer reported Flight Attendant noticed a smell of smoke about two hours into a transoceanic flight; so they declared an emergency and returned to departure airport.