Narrative:

On mar/sun/04, I performed the required preflight exterior inspection on aircraft X. My inspection of the exterior of the aircraft was normal and I observed no abnormalities. The flight from ZZZ1-ZZZ was flown by the first officer and was uneventful. I was notified at a later date that an investigation was being conducted on a missing panel of this aircraft after it arrived at ZZZ. Callback conversation with reporter revealed the following information: the reporter stated the cause of the access door departing the aircraft is unknown as the airplane appeared normal during the preflight inspection. The reporter said no access doors were unlatched or found missing during the preflight check, but on arrival the APU access door was found missing.

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Original NASA ASRS Text

Title: AN MD88 WAS DISCOVERED TO HAVE AN APU ACCESS PANEL MISSING. CAPT WHO INSPECTED ACFT PRIOR TO FLT FOUND ACFT IN NORMAL CONDITION.

Narrative: ON MAR/SUN/04, I PERFORMED THE REQUIRED PREFLT EXTERIOR INSPECTION ON ACFT X. MY INSPECTION OF THE EXTERIOR OF THE ACFT WAS NORMAL AND I OBSERVED NO ABNORMALITIES. THE FLT FROM ZZZ1-ZZZ WAS FLOWN BY THE FO AND WAS UNEVENTFUL. I WAS NOTIFIED AT A LATER DATE THAT AN INVESTIGATION WAS BEING CONDUCTED ON A MISSING PANEL OF THIS ACFT AFTER IT ARRIVED AT ZZZ. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE CAUSE OF THE ACCESS DOOR DEPARTING THE ACFT IS UNKNOWN AS THE AIRPLANE APPEARED NORMAL DURING THE PREFLT INSPECTION. THE RPTR SAID NO ACCESS DOORS WERE UNLATCHED OR FOUND MISSING DURING THE PREFLT CHK, BUT ON ARR THE APU ACCESS DOOR WAS FOUND MISSING.

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.