Narrative:

We were given a radio frequency change to atl approach. We checked in with atl approach and were told to cross canuk at 12000 ft MSL and then descend to 8000 ft MSL and also to get the new ATIS. (I believe we checked in with XXX and were told YYY was current.) I (first officer) was off frequency and my attention was diverted (getting ATIS) and the PF (captain) descended to approximately 11000 ft MSL over canuk intersection. No conflicts reported.

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Original NASA ASRS Text

Title: ACR MLG CAPT OVERSHOT DSCNT XING ALT BY 1000 FT BEFORE THE FO NOTICED THE MISTAKE.

Narrative: WE WERE GIVEN A RADIO FREQ CHANGE TO ATL APCH. WE CHKED IN WITH ATL APCH AND WERE TOLD TO CROSS CANUK AT 12000 FT MSL AND THEN DSND TO 8000 FT MSL AND ALSO TO GET THE NEW ATIS. (I BELIEVE WE CHKED IN WITH XXX AND WERE TOLD YYY WAS CURRENT.) I (FO) WAS OFF FREQ AND MY ATTN WAS DIVERTED (GETTING ATIS) AND THE PF (CAPT) DSNDED TO APPROX 11000 FT MSL OVER CANUK INTXN. NO CONFLICTS RPTED.

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.