Narrative:

Upon [reaching] level cruise flight at 330; cabin called with smell of burning rubber from mid aircraft area. The relief pilot was already in back so he went to check for odor. We were talking to departure and told them we may need to return to the departure airport. Also we began to shut down non-essential equipment; both utility busses and the inflight entertainment system. The relief pilot reported back that he could smell the burning rubber and that it seemed to dissipate after we turned off the non-essential equipment. We continued to coordinate with ATC to return to the departure airport. Since we were going to be overweight; we declared an emergency. We landed uneventfully 40 minutes later and had airport rescue and fire fighters inspect aircraft and then taxi to gate.

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Original NASA ASRS Text

Title: A B767-300 crew reported flight attendants detected a burning rubber smell in the mid cabin area so non-essential equipment was shutdown; an emergency declared and the flight returned to the departure airport.

Narrative: Upon [reaching] level cruise flight at 330; cabin called with smell of burning rubber from mid aircraft area. The Relief Pilot was already in back so he went to check for odor. We were talking to Departure and told them we may need to return to the departure airport. Also we began to shut down non-essential equipment; both utility busses and the inflight entertainment system. The Relief Pilot reported back that he could smell the burning rubber and that it seemed to dissipate after we turned off the non-essential equipment. We continued to coordinate with ATC to return to the departure airport. Since we were going to be overweight; we declared an emergency. We landed uneventfully 40 minutes later and had Airport Rescue and Fire Fighters inspect aircraft and then taxi to gate.

Data retrieved from NASA's ASRS site as of April 2012 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.