Narrative:

After servicing the #2 engine on this B727, I did not securely install the oil cap. It was found hanging by the lanyard when it reached its next destination airport. I certainly did not do this intentionally and am glad there was no damage to the aircraft/engine. I question the contractor's credibility, seeing as how the plane could not have flown from XXX to ZZZ without an oil cap. However, I signed off the engine items on the layover, so it's my responsibility.

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Original NASA ASRS Text

Title: A B727 WAS FOUND TO HAVE THE #2 ENG OIL CAP HANGING FROM ITS LANYARD ON ARR AT SDF.

Narrative: AFTER SVCING THE #2 ENG ON THIS B727, I DID NOT SECURELY INSTALL THE OIL CAP. IT WAS FOUND HANGING BY THE LANYARD WHEN IT REACHED ITS NEXT DEST ARPT. I CERTAINLY DID NOT DO THIS INTENTIONALLY AND AM GLAD THERE WAS NO DAMAGE TO THE ACFT/ENG. I QUESTION THE CONTRACTOR'S CREDIBILITY, SEEING AS HOW THE PLANE COULD NOT HAVE FLOWN FROM XXX TO ZZZ WITHOUT AN OIL CAP. HOWEVER, I SIGNED OFF THE ENG ITEMS ON THE LAYOVER, SO IT'S MY RESPONSIBILITY.

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.