Narrative:

I was informed by company personnel that maintenance found during their post flight inspection that our aircraft was missing a ram air inlet door. Mid station inspection by my flight engineer was normal and the ram air inlet door was intact. Maintenance also completed an aircraft walk around at this stop. The exact time and where the door had come loose is unknown as all indications on the flight deck were normal.

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Original NASA ASRS Text

Title: A B727 Captain reported being informed after the fact that that an aircraft he flew apparently lost a ram air inlet door in flight.

Narrative: I was informed by company personnel that maintenance found during their post flight inspection that our aircraft was missing a ram air inlet door. Mid station inspection by my flight engineer was normal and the ram air inlet door was intact. Maintenance also completed an aircraft walk around at this stop. The exact time and where the door had come loose is unknown as all indications on the flight deck were normal.

Data retrieved from NASA's ASRS site as of July 2013 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.