Narrative:

During cruise, a slight haze/smoke was noticed in the cockpit. A visual inspection of main cabin revealed moderate smoke. An immediate diversion to ZZZ was initiated. Smoke/fumes checklist accomplished. Emergency declared approaching ZZZ. 350 KIAS maintained until 15 NM final. Landing was uneventful. Note: smoke detectors did not alert crew to smoke. Callback conversation with reporter revealed the following information: callback revealed that once the decision was made to divert, it was approximately 30 mins to landing. The cabin was depressurized at FL250. Speed was maintained above 250 KTS below 10000 ft, because of the unknown source of the smoke and fumes. There was no documented hazmat on board, but there was a concern that there could be some anyway. High speed approachs had been previously trained for in simulator sessions. Airport fire crews met the aircraft and determined there was no fire. The source of the smoke was found to be oil in the pneumatic bleed system. With bleed valves deactivated closed, the aircraft was dispatched to a maintenance station. There it was borescoped and found that an oil seal had failed. The seal was removed, oil filter screens cleaned, and after coordination with the engine manufacturer, it was dispatched to the air carrier maintenance base with oil consumption monitoring as part of the MEL deferral requirement. After approximately 2 hours of flight, all oil was lost and engine bearing failure occurred.

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Original NASA ASRS Text

Title: CABIN SMOKE AND FUMES RESULTS IN AN EMER DIVERSION FOR AN MD11 CREW.

Narrative: DURING CRUISE, A SLIGHT HAZE/SMOKE WAS NOTICED IN THE COCKPIT. A VISUAL INSPECTION OF MAIN CABIN REVEALED MODERATE SMOKE. AN IMMEDIATE DIVERSION TO ZZZ WAS INITIATED. SMOKE/FUMES CHKLIST ACCOMPLISHED. EMER DECLARED APCHING ZZZ. 350 KIAS MAINTAINED UNTIL 15 NM FINAL. LNDG WAS UNEVENTFUL. NOTE: SMOKE DETECTORS DID NOT ALERT CREW TO SMOKE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: CALLBACK REVEALED THAT ONCE THE DECISION WAS MADE TO DIVERT, IT WAS APPROX 30 MINS TO LNDG. THE CABIN WAS DEPRESSURIZED AT FL250. SPD WAS MAINTAINED ABOVE 250 KTS BELOW 10000 FT, BECAUSE OF THE UNKNOWN SOURCE OF THE SMOKE AND FUMES. THERE WAS NO DOCUMENTED HAZMAT ON BOARD, BUT THERE WAS A CONCERN THAT THERE COULD BE SOME ANYWAY. HIGH SPD APCHS HAD BEEN PREVIOUSLY TRAINED FOR IN SIMULATOR SESSIONS. ARPT FIRE CREWS MET THE ACFT AND DETERMINED THERE WAS NO FIRE. THE SOURCE OF THE SMOKE WAS FOUND TO BE OIL IN THE PNEUMATIC BLEED SYS. WITH BLEED VALVES DEACTIVATED CLOSED, THE ACFT WAS DISPATCHED TO A MAINT STATION. THERE IT WAS BORESCOPED AND FOUND THAT AN OIL SEAL HAD FAILED. THE SEAL WAS REMOVED, OIL FILTER SCREENS CLEANED, AND AFTER COORD WITH THE ENG MANUFACTURER, IT WAS DISPATCHED TO THE ACR MAINT BASE WITH OIL CONSUMPTION MONITORING AS PART OF THE MEL DEFERRAL REQUIREMENT. AFTER APPROX 2 HRS OF FLT, ALL OIL WAS LOST AND ENG BEARING FAILURE OCCURRED.

Data retrieved from NASA's ASRS site as of July 2007 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.