Narrative:

I was the international relief officer on my break. About an hour into my break I smelled smoke and looked up and smoke was coming from seat 3A in front of our rest seat. I pushed the flight attendant call button to alert the flight attendants and got up and asked the passenger to move from the seat. The ism came over and said she shut off the electric power to the seat. The smell of the smoke was electrical. I opened up the seat to find out where the smoke was coming from. The smoke dissipated fast after power was removed and I felt around for hot spots. I found no real hot spots. The ism brought over the halon extinguisher and I moved out of the way for her to spray the spot where the smoke was coming from as a precaution. Myself as well as the flight attendants helping all felt around to make sure we felt no heat. After we felt there was no more fire threat I went over to the flight interphone and called the captain; [who] was on the satcom with dispatch as well as [maintenance] about the situation. [The captain] relayed the questions [maintenance] had to me and I answered their question. [Maintenance] advised to keep the ife power switch off and felt since the smoke was gone and there was no heat from where the smoke was coming from; we all agreed it was safe to continue. We believed the malfunction was from the seat motor and the threat was over after power was removed from the seat. The captain was confident that the problem was over [and] asked the rest of the crew if we all felt safe to proceed. We all felt safe to proceed and I asked the flight attendants to continually check the seat area around the seat motor to make sure there was no more heat while the flight continued.

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Original NASA ASRS Text

Title: B757 Relief Officer sitting in the cabin noticed smoke coming from another cabin seat. Smoke subsided when power was removed from seat.

Narrative: I was the IRO on my break. About an hour into my break I smelled smoke and looked up and smoke was coming from seat 3A in front of our rest seat. I pushed the FA call button to alert the flight attendants and got up and asked the passenger to move from the seat. The ISM came over and said she shut off the electric power to the seat. The smell of the smoke was electrical. I opened up the seat to find out where the smoke was coming from. The smoke dissipated fast after power was removed and I felt around for hot spots. I found no real hot spots. The ISM brought over the halon extinguisher and I moved out of the way for her to spray the spot where the smoke was coming from as a precaution. Myself as well as the flight attendants helping all felt around to make sure we felt no heat. After we felt there was no more fire threat I went over to the flight interphone and called the Captain; [who] was on the SATCOM with Dispatch as well as [Maintenance] about the situation. [The Captain] relayed the questions [Maintenance] had to me and I answered their question. [Maintenance] advised to keep the IFE power switch off and felt since the smoke was gone and there was no heat from where the smoke was coming from; we all agreed it was safe to continue. We believed the malfunction was from the seat motor and the threat was over after power was removed from the seat. The Captain was confident that the problem was over [and] asked the rest of the crew if we all felt safe to proceed. We all felt safe to proceed and I asked the flight attendants to continually check the seat area around the seat motor to make sure there was no more heat while the flight continued.

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.