Narrative:

Flight arrived at ZZZ. Performed exterior postflight inspection. Maintenance action was required for the lower beacon and VHF3; visually inspected both wing engines; visually checked oil quantity using the glass sight on the oil tank; noted oil quantity was within limits; no oil was added. Closed access doors and removed ladder. Flight diverted to ZZZ1 due to #1 engine oil pressure low. Found #1 engine oil cap off; not secure.

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Original NASA ASRS Text

Title: A Line Aircraft Maintenance Technician reported he performed a post flight exterior inspection of an MD-11 aircraft that included visually checking the engine oil quantities using the sight glass on the oil tanks. No oil was added. The flight later diverted due to low oil pressure on #1 engine. The oil tank cap was found off and not secured.

Narrative: Flight arrived at ZZZ. Performed exterior postflight inspection. Maintenance action was required for the lower beacon and VHF3; visually inspected both wing engines; visually checked oil quantity using the glass sight on the oil tank; noted oil quantity was within limits; no oil was added. Closed access doors and removed ladder. Flight diverted to ZZZ1 due to #1 Engine oil pressure low. Found #1 Engine oil cap off; not secure.

Data retrieved from NASA's ASRS site 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.