Narrative:

We were assigned to cross druzz at 11000 ft, 250 KTS. Left FL250 about 30 NM west of esl. We crossed druzz at 15000 ft, 250 KTS. Our mistake was realized when the controller cleared us to 10000 ft and the copilot looked at the altitude alerter to reset it. We had been in daylight conditions until starting the descent. During the descent we turned the lights down. Shortly after we received the clearance for druzz, another aircraft was cleared to cross druzz at 15000 ft. I must have mentally keyed in this and missed the visual cue, the altitude alerter and chart as the lights were being turned down.

Google
 

Original NASA ASRS Text

Title: A DC9 PIC FAILS TO MAKE AN ALT XING RESTR WHEN MENTALLY SUBSTITUTING ANOTHER FLT'S CLRNC FOR HIS OWN IN XING DRUZZ INTXN OFF ESL VOR, WV.

Narrative: WE WERE ASSIGNED TO CROSS DRUZZ AT 11000 FT, 250 KTS. LEFT FL250 ABOUT 30 NM W OF ESL. WE CROSSED DRUZZ AT 15000 FT, 250 KTS. OUR MISTAKE WAS REALIZED WHEN THE CTLR CLRED US TO 10000 FT AND THE COPLT LOOKED AT THE ALT ALERTER TO RESET IT. WE HAD BEEN IN DAYLIGHT CONDITIONS UNTIL STARTING THE DSCNT. DURING THE DSCNT WE TURNED THE LIGHTS DOWN. SHORTLY AFTER WE RECEIVED THE CLRNC FOR DRUZZ, ANOTHER ACFT WAS CLRED TO CROSS DRUZZ AT 15000 FT. I MUST HAVE MENTALLY KEYED IN THIS AND MISSED THE VISUAL CUE, THE ALT ALERTER AND CHART AS THE LIGHTS WERE BEING TURNED DOWN.

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.