Narrative:

Aircraft had maintenance work for an oil leak from the #1 engine prior to this incident. We flew this aircraft on the morning of feb/wed/07. During cruise at FL340 just west of gjt; the first officer noticed #1 oil quantity at 32%. I sent a message to maintenance to request they look at the engine data. They responded that the aircraft had an oil leak history so it's possible this was recurring. Dispatch was also notified at this point. As a crew; we began reviewing WX along the route. Oil quantity continued to decrease and was indicating 28%. All other engine parameters continued to show normal. At this point; notified purser of the situation and issued a cabin advisory. I asked maintenance if we could expect to see normal indications until the time oil quantity was lost. At this point; still not certain if true leak or indicator problem; however; with history; suspected it was a real leak. Approximately 75 NM from ZZZ; #1 oil pressure started to show a decrease. Decided to divert to ZZZ. Did not declare an emergency. In retrospect; should have done this immediately. First officer flying the aircraft and myself completing necessary duties. ATC issued direct VOR direct ZZZ. Declaring emergency would have allowed us to go direct ZZZ immediately. Still amazed at how workload increases in a 2-PLT jet; even with lead time to consider action options. Good communication and idea exchanger between captain and first officer. Dispatch declared emergency for us with ATC. On final approach; oil pressure was in caution range. By 500 ft on final; low oil pressure light began to flicker on and off. Landed without incident after nice approach by first officer. Turned off runway and shut down #1 engine while having aircraft inspected by crash fire rescue equipment units. Taxied to gate. If flight was; say 5 mins longer; we would have needed to shut the engine down in-flight.

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Original NASA ASRS Text

Title: B733 CREW REPORTS OIL LOSS WHILE IN CRUISE AND DECISION TO DIVERT AS OIL PRESSURE STARTS TO FLUCTUATE.

Narrative: ACFT HAD MAINT WORK FOR AN OIL LEAK FROM THE #1 ENG PRIOR TO THIS INCIDENT. WE FLEW THIS ACFT ON THE MORNING OF FEB/WED/07. DURING CRUISE AT FL340 JUST W OF GJT; THE FO NOTICED #1 OIL QUANTITY AT 32%. I SENT A MESSAGE TO MAINT TO REQUEST THEY LOOK AT THE ENG DATA. THEY RESPONDED THAT THE ACFT HAD AN OIL LEAK HISTORY SO IT'S POSSIBLE THIS WAS RECURRING. DISPATCH WAS ALSO NOTIFIED AT THIS POINT. AS A CREW; WE BEGAN REVIEWING WX ALONG THE RTE. OIL QUANTITY CONTINUED TO DECREASE AND WAS INDICATING 28%. ALL OTHER ENG PARAMETERS CONTINUED TO SHOW NORMAL. AT THIS POINT; NOTIFIED PURSER OF THE SIT AND ISSUED A CABIN ADVISORY. I ASKED MAINT IF WE COULD EXPECT TO SEE NORMAL INDICATIONS UNTIL THE TIME OIL QUANTITY WAS LOST. AT THIS POINT; STILL NOT CERTAIN IF TRUE LEAK OR INDICATOR PROB; HOWEVER; WITH HISTORY; SUSPECTED IT WAS A REAL LEAK. APPROX 75 NM FROM ZZZ; #1 OIL PRESSURE STARTED TO SHOW A DECREASE. DECIDED TO DIVERT TO ZZZ. DID NOT DECLARE AN EMER. IN RETROSPECT; SHOULD HAVE DONE THIS IMMEDIATELY. FO FLYING THE ACFT AND MYSELF COMPLETING NECESSARY DUTIES. ATC ISSUED DIRECT VOR DIRECT ZZZ. DECLARING EMER WOULD HAVE ALLOWED US TO GO DIRECT ZZZ IMMEDIATELY. STILL AMAZED AT HOW WORKLOAD INCREASES IN A 2-PLT JET; EVEN WITH LEAD TIME TO CONSIDER ACTION OPTIONS. GOOD COM AND IDEA EXCHANGER BTWN CAPT AND FO. DISPATCH DECLARED EMER FOR US WITH ATC. ON FINAL APCH; OIL PRESSURE WAS IN CAUTION RANGE. BY 500 FT ON FINAL; LOW OIL PRESSURE LIGHT BEGAN TO FLICKER ON AND OFF. LANDED WITHOUT INCIDENT AFTER NICE APCH BY FO. TURNED OFF RWY AND SHUT DOWN #1 ENG WHILE HAVING ACFT INSPECTED BY CFR UNITS. TAXIED TO GATE. IF FLT WAS; SAY 5 MINS LONGER; WE WOULD HAVE NEEDED TO SHUT THE ENG DOWN INFLT.

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.