Narrative:

Aircraft was assigned 13000 ft by ATC. ATC notified crew as the aircraft passed 11700 ft. ATC immediately assigned a lower altitude.

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Original NASA ASRS Text

Title: THE RPTR DSNDED THROUGH THE ASSIGNED 13000 FT TO 11700 FT BEFORE THE CTRL NOTIFIED THE CREW AND ASSIGNED A LOWER ALT.

Narrative: ACFT WAS ASSIGNED 13000 FT BY ATC. ATC NOTIFIED CREW AS THE ACFT PASSED 11700 FT. ATC IMMEDIATELY ASSIGNED A LOWER ALT.

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.