Narrative:

During cruise, #2 engine low oil pressure light began to flicker. Confirmed oil pressure was decreasing by gauge. Oil pressure went below acceptable limits. During this time I called mechanic on flight phone. He realized he had left oil cap off engine during servicing. I shut down engine per checklist, drifted down to FL290, and secured engine. Copilot and I discussed our options. We were 1 1/2 hours from destination with a mechanic waiting. I elected to proceed on to destination. Rest of the flight was uneventful. I must say I will personally check oil caps before each flight. It was my responsibility to make sure the aircraft was in airworthy condition. I relied on a trustworthy mechanic, but it isn't a perfect world.

Google
 

Original NASA ASRS Text

Title: CORP TRI-JET LOSES OIL AND SUFFERS AN INFLT ENG SHUTDOWN.

Narrative: DURING CRUISE, #2 ENG LOW OIL PRESSURE LIGHT BEGAN TO FLICKER. CONFIRMED OIL PRESSURE WAS DECREASING BY GAUGE. OIL PRESSURE WENT BELOW ACCEPTABLE LIMITS. DURING THIS TIME I CALLED MECH ON FLT PHONE. HE REALIZED HE HAD LEFT OIL CAP OFF ENG DURING SVCING. I SHUT DOWN ENG PER CHKLIST, DRIFTED DOWN TO FL290, AND SECURED ENG. COPLT AND I DISCUSSED OUR OPTIONS. WE WERE 1 1/2 HRS FROM DEST WITH A MECH WAITING. I ELECTED TO PROCEED ON TO DEST. REST OF THE FLT WAS UNEVENTFUL. I MUST SAY I WILL PERSONALLY CHK OIL CAPS BEFORE EACH FLT. IT WAS MY RESPONSIBILITY TO MAKE SURE THE ACFT WAS IN AIRWORTHY CONDITION. I RELIED ON A TRUSTWORTHY MECH, BUT IT ISN'T A PERFECT WORLD.

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.