Narrative:

Aircraft X was at 15000 ft cleared to hold. Aircraft Y was descending to 16000 ft and unable to hold. I began to descend aircraft X to 13000 ft, but told him to disregard and maintain 15000 ft. Aircraft Y read back clearance to 15000 ft. I did not catch it.

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Original NASA ASRS Text

Title: ACFT X WAS CLRED TO HOLD AT 15000 FT. ACFT Y WAS STOPPED AT 16000 FT. ACFT X WAS GIVEN A CLRNC TO DSND TO 13000 FT AND THEN TOLD TO DISREGARD. ACFT X ACKNOWLEDGED THE CLRNC AND RPTR DID NOT CATCH IT RESULTING IN A LOSS OF STANDARD SEPARATION.

Narrative: ACFT X WAS AT 15000 FT CLRED TO HOLD. ACFT Y WAS DSNDING TO 16000 FT AND UNABLE TO HOLD. I BEGAN TO DSND ACFT X TO 13000 FT, BUT TOLD HIM TO DISREGARD AND MAINTAIN 15000 FT. ACFT Y READ BACK CLRNC TO 15000 FT. I DID NOT CATCH IT.

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.