B757-200
Flight Crew Last 90 Days 200; Flight Crew Total 10000; Flight Crew Type 5000
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Flight Crew Landed As Precaution; Flight Crew Returned To Departure Airport
Aircraft
Just prior to coast out the Purser called the flight deck to say there was a burn spot on the side panel next to 20F and it was very hot to the touch. We asked the IRO who was on break to investigate it. He confirmed what the Purser said. The IRO came up so the Captain could go back and investigate and he confirmed something was burning in the side wall. While he was in the back; I coordinated with Maintenance Control via Satcom. The Captain came back and was agreed it was unsafe to cross the water with an uncontrollable and unknown heat source in the side panel. We advised ATC and returned to departure airport.
Over wing hatch heater at row 20 seat F; overheated. Unable to control and isolate. Plastic molding was showing signs of heat damage (big black spot) Unable to touch due to heat. Conference call with Maintenance and Duty Manager. Returned to departure airport.
B757 flight crew is informed of burn marks on the right emergency exit door by the Purser. The First Officer on break investigates and determines there is a burn mark plus several other hot spots on the door. The crew elects to return to the departure airport.