Narrative:

Air carrier X at FL350 swbound over pxv. Air carrier Y at FL370 nebound approaching pxv. Reported turbulence and requested lower. Air carrier X was overlooked and air carrier Y was descended to FL330. When the conflict was noticed, air carrier Y was turned 30 degrees left and told of the traffic. Air carrier Y reported he had the aircraft on TCASII.

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Original NASA ASRS Text

Title: ACR Y DSCNT THROUGH OCCUPIED ALT HAD LTSS FROM ACR X. SYS ERROR.

Narrative: ACR X AT FL350 SWBOUND OVER PXV. ACR Y AT FL370 NEBOUND APCHING PXV. RPTED TURB AND REQUESTED LOWER. ACR X WAS OVERLOOKED AND ACR Y WAS DSNDED TO FL330. WHEN THE CONFLICT WAS NOTICED, ACR Y WAS TURNED 30 DEGS L AND TOLD OF THE TFC. ACR Y RPTED HE HAD THE ACFT ON TCASII.

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.