Narrative:

After several minutes at cruise altitude (11000') ATC queried us regarding our altitude and said that our assigned altitude was 10000'. Both pilots remembered being assigned 11000' and in fact 11000' was set in the altitude preselect window. Since our filed altitude was 10000', pilots probably should have questioned the 11000' altitude assignment.

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Original NASA ASRS Text

Title: CGA ACFT CLIMBED TO 11000' MSL IN SUPPOSED COMPLIANCE WITH COPIED CLRNC. HAD FILED V47 SOUTHWESTBOUND, 10000'. ATC QUERY OF ALT BROUGHT ABOUT RECLRNC TO 10000'. NO CONFLICT.

Narrative: AFTER SEVERAL MINUTES AT CRUISE ALT (11000') ATC QUERIED US REGARDING OUR ALT AND SAID THAT OUR ASSIGNED ALT WAS 10000'. BOTH PLTS REMEMBERED BEING ASSIGNED 11000' AND IN FACT 11000' WAS SET IN THE ALT PRESELECT WINDOW. SINCE OUR FILED ALT WAS 10000', PLTS PROBABLY SHOULD HAVE QUESTIONED THE 11000' ALT ASSIGNMENT.

Data retrieved from NASA's ASRS site as of August 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.