Narrative:

Oil contaminated air pack. On taxi out advised by flight attendant that there was smoke in the 2L lav and the smoke detector was going off. No significant smoke or fire were observed. Returned to gate. Maintenance determined that cause was oil from overnight maintenance conducted on meled APU contaminating air pack.

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Original NASA ASRS Text

Title: AN OIL CONTAMINATED ACFT PACK CAUSE LAV SMOKE DURING TAXI OUT FOR TKOF. ACFT RETURNED TO GATE FOR MAINT.

Narrative: OIL CONTAMINATED AIR PACK. ON TAXI OUT ADVISED BY FLT ATTENDANT THAT THERE WAS SMOKE IN THE 2L LAV AND THE SMOKE DETECTOR WAS GOING OFF. NO SIGNIFICANT SMOKE OR FIRE WERE OBSERVED. RETURNED TO GATE. MAINT DETERMINED THAT CAUSE WAS OIL FROM OVERNIGHT MAINT CONDUCTED ON MELED APU CONTAMINATING AIR PACK.

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.