Narrative:

Controller gave climb from FL310 to FL330. I read back climbing to FL350. At FL340, controller asked altitude and told us to descend to FL330. First officer was on PA during first radio call. Supplemental information from acn 314320: first officer was making seatbelt PA announcement. At FL340, the first officer returned to monitoring the radios when ATC questioned our altitude and stated we were cleared to FL330. The center was advised that the readback was FL350.

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Original NASA ASRS Text

Title: ACR DC9-50 FLC COPIED CLRNC AND READ BACK SAME WHILE ENRTE. CLRNC COMPLIANCE WAS MET WITH CTLR QUERY AND INSTRUCTIONS TO RETURN TO CORRECT FLT LEVEL.

Narrative: CTLR GAVE CLB FROM FL310 TO FL330. I READ BACK CLBING TO FL350. AT FL340, CTLR ASKED ALT AND TOLD US TO DSND TO FL330. FO WAS ON PA DURING FIRST RADIO CALL. SUPPLEMENTAL INFO FROM ACN 314320: FO WAS MAKING SEATBELT PA ANNOUNCEMENT. AT FL340, THE FO RETURNED TO MONITORING THE RADIOS WHEN ATC QUESTIONED OUR ALT AND STATED WE WERE CLRED TO FL330. THE CTR WAS ADVISED THAT THE READBACK WAS FL350.

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.