Narrative:

Controller cleared us to 8000 ft. Climbed to 8000 ft, both captain and first officer heard and repeated 8000 ft and entered in altitude alerter. Upon level off controller then said he had cleared us to only 7000 ft but we were now cleared to 9000 ft. Captain radioed back that he had read back 8000 ft. No conflict noted on TCASII. No further response from controller.

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Original NASA ASRS Text

Title: ACKNOWLEDGE CLRNC TO 8000 FT. LEAVING 7500 FT CTLR ADVISED ONLY CLRED TO 7000 FT, NOW MAINTAIN 9000 FT. BE02.

Narrative: CTLR CLRED US TO 8000 FT. CLBED TO 8000 FT, BOTH CAPT AND FO HEARD AND REPEATED 8000 FT AND ENTERED IN ALT ALERTER. UPON LEVEL OFF CTLR THEN SAID HE HAD CLRED US TO ONLY 7000 FT BUT WE WERE NOW CLRED TO 9000 FT. CAPT RADIOED BACK THAT HE HAD READ BACK 8000 FT. NO CONFLICT NOTED ON TCASII. NO FURTHER RESPONSE FROM CTLR.

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.