Narrative:

Approximately 15 mins into the flight; approaching the ZZZ VOR we noted a change in the sound of the aircraft. We attempted to isolate the source of the sound by changing engine RPM; securing bleeds; etc; but were unable to do so. Shortly after turning over ZZZ1 about 10 mi from ZZZ VOR toward ZZZ1 VOR the noise level changed in both pitch and volume. We made a normal landing on runway X at ZZZ; taxied in; and shut down. On postflt the first officer noted the fuel door was missing. Redesign the door so that it fares into the windstream in the event of a latch failure.

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Original NASA ASRS Text

Title: A LR40 CREW REPORTS A FUEL PANEL DOOR CAME OFF IN FLT. THE DISCOVERY WAS MADE ON POST FLT AFTER LOUD WIND NOISES WERE HEARD IN FLT.

Narrative: APPROX 15 MINS INTO THE FLT; APCHING THE ZZZ VOR WE NOTED A CHANGE IN THE SOUND OF THE ACFT. WE ATTEMPTED TO ISOLATE THE SOURCE OF THE SOUND BY CHANGING ENG RPM; SECURING BLEEDS; ETC; BUT WERE UNABLE TO DO SO. SHORTLY AFTER TURNING OVER ZZZ1 ABOUT 10 MI FROM ZZZ VOR TOWARD ZZZ1 VOR THE NOISE LEVEL CHANGED IN BOTH PITCH AND VOLUME. WE MADE A NORMAL LNDG ON RWY X AT ZZZ; TAXIED IN; AND SHUT DOWN. ON POSTFLT THE FO NOTED THE FUEL DOOR WAS MISSING. REDESIGN THE DOOR SO THAT IT FARES INTO THE WINDSTREAM IN THE EVENT OF A LATCH FAILURE.

Data retrieved from NASA's ASRS site as of May 2009 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.