Narrative:

I was on third break as PNF and as I walked into the cockpit; an altitude was given and read back. The altitude was set and aircraft descended. As we leveled off; ATC called and asked what altitude we were cleared to (I think 14000 ft versus 16000 ft) and captain responded. Upon being told we were at the wrong altitude; we asked if we needed to correct and they said not to worry about it as we made our apologies.

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Original NASA ASRS Text

Title: A B767-300 DSNDED INTO AND LEVELED OFF AT THE WRONG ALT. ATC ADVISED CREW OF WRONG ALT. NO CORRECTIVE ACTION REQUIRED.

Narrative: I WAS ON THIRD BREAK AS PNF AND AS I WALKED INTO THE COCKPIT; AN ALT WAS GIVEN AND READ BACK. THE ALT WAS SET AND ACFT DSNDED. AS WE LEVELED OFF; ATC CALLED AND ASKED WHAT ALT WE WERE CLRED TO (I THINK 14000 FT VERSUS 16000 FT) AND CAPT RESPONDED. UPON BEING TOLD WE WERE AT THE WRONG ALT; WE ASKED IF WE NEEDED TO CORRECT AND THEY SAID NOT TO WORRY ABOUT IT AS WE MADE OUR APOLOGIES.

Data retrieved from NASA's ASRS site as of January 2009 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.