Narrative:

Aircraft log xyzwz. On takeoff, the left side aft lavatory smoke detector went off and the aft flight attendants smelled a faint burning odor. No smoke was visible in the lavatory or cabin. The odor cleared up by 10000 ft. Corrective action: ran engines to takeoff power. On initial run, got some oily type smell. With xfeeds closed and APU air off on several successive runs, no smell or problems noted. Forward APU air to xzx/placard MEL xx-yy. After approximately 1 hour of takeoff power engine runs, using approximately 18000 pounds of fuel, aircraft showed no further problems. Based on approved maintenance practices, I feel I used sound judgement in my actions.

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Original NASA ASRS Text

Title: AN MD88 RETURNED TO THE FIELD DUE TO A L AFT LAVATORY SMOKE DETECTOR WARNING CAUSED BY THE APU LEAKING OIL INTO THE AIR CONDITIONING PNEUMATIC DUCTS.

Narrative: ACFT LOG XYZWZ. ON TKOF, THE L SIDE AFT LAVATORY SMOKE DETECTOR WENT OFF AND THE AFT FLT ATTENDANTS SMELLED A FAINT BURNING ODOR. NO SMOKE WAS VISIBLE IN THE LAVATORY OR CABIN. THE ODOR CLRED UP BY 10000 FT. CORRECTIVE ACTION: RAN ENGS TO TKOF PWR. ON INITIAL RUN, GOT SOME OILY TYPE SMELL. WITH XFEEDS CLOSED AND APU AIR OFF ON SEVERAL SUCCESSIVE RUNS, NO SMELL OR PROBS NOTED. FORWARD APU AIR TO XZX/PLACARD MEL XX-YY. AFTER APPROX 1 HR OF TKOF PWR ENG RUNS, USING APPROX 18000 LBS OF FUEL, ACFT SHOWED NO FURTHER PROBS. BASED ON APPROVED MAINT PRACTICES, I FEEL I USED SOUND JUDGEMENT IN MY ACTIONS.

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.