Narrative:

ATC cleared the aircraft to maintain 9000 ft. During climb to 9000 ft, ATC reclred the aircraft to maintain 13000 ft. Passing through 10300 ft, ATC queried the aircraft about altitude. The crew responded with 10300 ft. ATC stated that the aircraft was only cleared to 9000 ft. The crew responded that the aircraft had been cleared to 13000 ft. ATC reclred the aircraft to maintain 9000 ft. The crew then descended to 9000 ft without further incident or comment from ATC. No traffic conflict occurred, no other aircraft appeared on TCASII with unit set on 12 NM range.

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Original NASA ASRS Text

Title: DC9 FLC RPT WHILE PASSING 10300 FT AFTER BEING RECLRED FROM 9000 FT TO 13000 FT, THE CTLR STATED THAT THEY WERE ONLY CLRED TO 9000 FT.

Narrative: ATC CLRED THE ACFT TO MAINTAIN 9000 FT. DURING CLB TO 9000 FT, ATC RECLRED THE ACFT TO MAINTAIN 13000 FT. PASSING THROUGH 10300 FT, ATC QUERIED THE ACFT ABOUT ALT. THE CREW RESPONDED WITH 10300 FT. ATC STATED THAT THE ACFT WAS ONLY CLRED TO 9000 FT. THE CREW RESPONDED THAT THE ACFT HAD BEEN CLRED TO 13000 FT. ATC RECLRED THE ACFT TO MAINTAIN 9000 FT. THE CREW THEN DSNDED TO 9000 FT WITHOUT FURTHER INCIDENT OR COMMENT FROM ATC. NO TFC CONFLICT OCCURRED, NO OTHER ACFT APPEARED ON TCASII WITH UNIT SET ON 12 NM RANGE.

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.