Narrative:

Approximately 5 hours into the flight; both the first officer and I smelled a very strong electrical burning odor in the cockpit. As we were discussing it; the purser called from first class saying she smelled a very strong electrical odor in the first class cabin. I instructed her to immediately turn off the passenger entertainment power and the galley power and to feel floors and bulkheads for heat. No smoke was observed either in the cabin or cockpit. We then donned oxygen masks and goggles and accomplished the smoke fumes odor qrc followed by the electrical smoke irregular procedure. The purser called back to say everything looked and felt normal except that a first class lavatory had a warm wall and was venting warm air. She didn't know if this was normal or not as the same lavatory on the opposite side of the cabin did not feel warm. I woke one of the bunkies who was on break and instructed him to go to the first class cabin to help the purser look for the source of the smell. Just about that time the purser called back to say that the odor seemed to have stopped and we noticed the same in the cockpit. When the first officer went to the cabin a passenger in row 4 where the odor had been the worst said that as soon as the video screen went blank (power removed) the odor stopped. Since we were over the north pacific at night and several hundred mi from a suitable airport; I elected not to turn anything back on except the galleys. I had the purser turn the galley power back on and make sure that no smoke or odor returned. No odor returned so we stayed in that confign for the remainder of the flight. The passenger were without video entertainment for the remainder of the flight with only a few complaints. System aircraft maintenance controller entered the item into log and the rest of the flight was normal. A few thoughts on this incident: 1) this was the first time that I put on the oxygen mask and goggles in the real airplane. I use reading glasses and I found how difficult it is to accomplish a checklist under these conditions. A 1-PIECE mask/goggle would be far superior. 2) nowhere in the flight manual emergency qrc or irregular procedure does it instruct you to turn off or even consider turning off the passenger entertainment system or galleys. As these are very common sources of smoke or odor and have even caused crashes in the past; I think that at least a note if not a procedural step in the checklists would be a good idea.

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Original NASA ASRS Text

Title: A B747-400 RPTS CAPT AND FO SMELLED STRONG ELECTRICAL BURNING ODOR. CABIN ATTENDANT ALSO RPTED ODOR IN FIRST CLASS. CAUSED BY VIDEO PROJECTOR.

Narrative: APPROX 5 HRS INTO THE FLT; BOTH THE FO AND I SMELLED A VERY STRONG ELECTRICAL BURNING ODOR IN THE COCKPIT. AS WE WERE DISCUSSING IT; THE PURSER CALLED FROM FIRST CLASS SAYING SHE SMELLED A VERY STRONG ELECTRICAL ODOR IN THE FIRST CLASS CABIN. I INSTRUCTED HER TO IMMEDIATELY TURN OFF THE PAX ENTERTAINMENT PWR AND THE GALLEY PWR AND TO FEEL FLOORS AND BULKHEADS FOR HEAT. NO SMOKE WAS OBSERVED EITHER IN THE CABIN OR COCKPIT. WE THEN DONNED OXYGEN MASKS AND GOGGLES AND ACCOMPLISHED THE SMOKE FUMES ODOR QRC FOLLOWED BY THE ELECTRICAL SMOKE IRREGULAR PROC. THE PURSER CALLED BACK TO SAY EVERYTHING LOOKED AND FELT NORMAL EXCEPT THAT A FIRST CLASS LAVATORY HAD A WARM WALL AND WAS VENTING WARM AIR. SHE DIDN'T KNOW IF THIS WAS NORMAL OR NOT AS THE SAME LAVATORY ON THE OPPOSITE SIDE OF THE CABIN DID NOT FEEL WARM. I WOKE ONE OF THE BUNKIES WHO WAS ON BREAK AND INSTRUCTED HIM TO GO TO THE FIRST CLASS CABIN TO HELP THE PURSER LOOK FOR THE SOURCE OF THE SMELL. JUST ABOUT THAT TIME THE PURSER CALLED BACK TO SAY THAT THE ODOR SEEMED TO HAVE STOPPED AND WE NOTICED THE SAME IN THE COCKPIT. WHEN THE FO WENT TO THE CABIN A PAX IN ROW 4 WHERE THE ODOR HAD BEEN THE WORST SAID THAT AS SOON AS THE VIDEO SCREEN WENT BLANK (PWR REMOVED) THE ODOR STOPPED. SINCE WE WERE OVER THE NORTH PACIFIC AT NIGHT AND SEVERAL HUNDRED MI FROM A SUITABLE ARPT; I ELECTED NOT TO TURN ANYTHING BACK ON EXCEPT THE GALLEYS. I HAD THE PURSER TURN THE GALLEY PWR BACK ON AND MAKE SURE THAT NO SMOKE OR ODOR RETURNED. NO ODOR RETURNED SO WE STAYED IN THAT CONFIGN FOR THE REMAINDER OF THE FLT. THE PAX WERE WITHOUT VIDEO ENTERTAINMENT FOR THE REMAINDER OF THE FLT WITH ONLY A FEW COMPLAINTS. SYS ACFT MAINT CTLR ENTERED THE ITEM INTO LOG AND THE REST OF THE FLT WAS NORMAL. A FEW THOUGHTS ON THIS INCIDENT: 1) THIS WAS THE FIRST TIME THAT I PUT ON THE OXYGEN MASK AND GOGGLES IN THE REAL AIRPLANE. I USE READING GLASSES AND I FOUND HOW DIFFICULT IT IS TO ACCOMPLISH A CHKLIST UNDER THESE CONDITIONS. A 1-PIECE MASK/GOGGLE WOULD BE FAR SUPERIOR. 2) NOWHERE IN THE FLT MANUAL EMER QRC OR IRREGULAR PROC DOES IT INSTRUCT YOU TO TURN OFF OR EVEN CONSIDER TURNING OFF THE PAX ENTERTAINMENT SYS OR GALLEYS. AS THESE ARE VERY COMMON SOURCES OF SMOKE OR ODOR AND HAVE EVEN CAUSED CRASHES IN THE PAST; I THINK THAT AT LEAST A NOTE IF NOT A PROCEDURAL STEP IN THE CHKLISTS WOULD BE A GOOD IDEA.

Data retrieved from NASA's ASRS site as of January 2009 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.