ACR Y DSCNT TO OCCUPIED ALT HAD LTSS FROM MLT X. SYS ERROR.

Narrative

MLT X WAS TFC FOR STL INBOUNDS. A J-RING WAS PUT ON MLT X DATA BLOCK. HAVING STOPPED ANOTHER INBOUND AT FL250; UNTIL PASSED MLT X. FL250 WAS THE CLRNC THOUGHT TO HAVE BEEN ISSUED TO ACR Y. AFTER NOTICING ACR Y DSNDING THROUGH FL244; ACR Y WAS TURNED 90 DEG L AND DSNDED TO FL230. THEN MLT X WAS TURNED 90 DEG R. TFC WAS ISSUED TO ACR Y AND ASKED SLT. ACR Y REPLIED 'FL230.' ACR Y CLRED TO REJOIN MODUC 5 ARR. MLT X CLRED BACK ON COURSE. ACR Y RPTED ON FREQ AT 3100 FT. SECTOR 14 RADAR ISSUED A HDG OF 250 FOR SPACING TO ACR Y. SECTOR 14 RADAR CLRED ACR Y TO DSND TO 2600 FT. SECTOR 14 RADAR ISSUED A HDG OF 270; TO JOIN THE MODUC5 ARR; TO ACR Y. SECTOR 14 RADAR CLRED ACR Y TO DSND TO 24000 FT. SECTOR 14 RADAR CTLR ENTERS A TEMPORARY ALT OF 24000 FT IN THE DATA BLOCK OF ACR Y. SECTOR 14 RADAR ISSUED TFC TO MLT X ON ACR Y DSNDING TO 25000 FT. SECTOR 14 RADAR CTLR ENTERS A TEMPORARY ALT OF 25000 FT IN THE DATA BLOCK OF ACR Y. CONFLICT ALERT ACTIVATES; ACR Y AT 24400 FT. SECTOR 14 RADAR DSNDED ACR Y TO 23000 FT AND ISSUED A 90 DEG TURN TO THE L. SECTOR 14 RADAR ISSUED A 90 DEG R TURN TO MLT X. LOSS OF SEPARATION; CLOSEST POINT 4.4 MI AND 300 FT. ACR Y RPTED LEVEL AT 2300 FT; SEPARATION REESTABLISHED. SECTOR 14 RADAR ISSUED A HDG OF 295 TO JOIN THE MODUC5 ARR.