Narrative:

Returning to aircraft 20 mins prior to blockout time, found company maintenance crew performing 'a' check (required every 48 hours). Crew received logbook and aircraft back 10 mins prior to blockout. Immediately boarded passenger. One passenger seated next to right (#2) engine told me that an access panel was open. I noted it and asked ground crew to secure it. It was the oil dipstick panel. Late passenger arrived and after boarding them, I performed a quick walkaround looking for loose panels and doors. All ok. Past engine start time and still had to give passenger safety briefing. Briefing completed, start, taxi, takeoff normal. Only 3 mins late. On climbout at 2500' a jumpseat captain entered the cockpit to inform me that 'you have a significant fluid loss on right turbine'. All engine instruments normal still. Had first officer check his engine nacelle and he confirmed a leak. Now #2 oil pressure began slight fluctuation. It intermittently dropped about 5 psi about once per second. At that time I elected to return to sfo and notified departure control. They immediately notified sfo tower and cleared me for return to runway 28R (takeoff had been on 01R).

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Original NASA ASRS Text

Title: ACR SMT EXPERIENCED LOSS OF OIL QUANTITY ON ONE ENGINE AFTER TKOF ACCOMPANIED BY FLUCTUATING OIL PRESSURE NECESSITATING A RETURN TO DEP ARPT.

Narrative: RETURNING TO ACFT 20 MINS PRIOR TO BLOCKOUT TIME, FOUND COMPANY MAINT CREW PERFORMING 'A' CHECK (REQUIRED EVERY 48 HRS). CREW RECEIVED LOGBOOK AND ACFT BACK 10 MINS PRIOR TO BLOCKOUT. IMMEDIATELY BOARDED PAX. ONE PAX SEATED NEXT TO RIGHT (#2) ENGINE TOLD ME THAT AN ACCESS PANEL WAS OPEN. I NOTED IT AND ASKED GND CREW TO SECURE IT. IT WAS THE OIL DIPSTICK PANEL. LATE PAX ARRIVED AND AFTER BOARDING THEM, I PERFORMED A QUICK WALKAROUND LOOKING FOR LOOSE PANELS AND DOORS. ALL OK. PAST ENGINE START TIME AND STILL HAD TO GIVE PAX SAFETY BRIEFING. BRIEFING COMPLETED, START, TAXI, TKOF NORMAL. ONLY 3 MINS LATE. ON CLIMBOUT AT 2500' A JUMPSEAT CAPT ENTERED THE COCKPIT TO INFORM ME THAT 'YOU HAVE A SIGNIFICANT FLUID LOSS ON RIGHT TURBINE'. ALL ENGINE INSTRUMENTS NORMAL STILL. HAD F/O CHECK HIS ENGINE NACELLE AND HE CONFIRMED A LEAK. NOW #2 OIL PRESSURE BEGAN SLIGHT FLUCTUATION. IT INTERMITTENTLY DROPPED ABOUT 5 PSI ABOUT ONCE PER SECOND. AT THAT TIME I ELECTED TO RETURN TO SFO AND NOTIFIED DEP CTL. THEY IMMEDIATELY NOTIFIED SFO TWR AND CLRED ME FOR RETURN TO RWY 28R (TKOF HAD BEEN ON 01R).

Data retrieved from NASA's ASRS site as of August 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.