LESS THAN STANDARD SEPARATION WHEN ACR MDT IS DESCENDED TO THE ALT OF SMT NOT DISPLAYED ON CTLR'S RADAR.

Narrative

MDT X AND SMT Y WERE HANDED OFF TO THE CTLR APPROX 20 TO 25 MI FROM THE POINT OF THE IDENT DEV. MDT X WAS EBND AT 7000 AND SMT Y WAS NBOUND AT 6000. MDT X WAS DSNDED TO 6000 BY THE CTLR AFTER IT ENTERED HIS AIRSPACE. SMT Y WAS NEVER FREQ CHANGED BY THE OTHER SECTOR TO THE NEW CTLR. HANDOFFS WERE ACCOMPLISHED THROUGH ARTS AUTOMATION. WITHIN 5 MI OF THE RADAR CENTER 'MAIN BANG'; BOTH TAGS OF THE RESPECTIVE ACFT DROPPED AND DID NOT REACQUIRE UNTIL AFTER THE ERROR HAD OCCURRED AND BOTH ACFT WERE NOW N AND E OF THE CENTER BY AT LEAST 5 MI. SMT Y RPTED HAVING MDT X IN SIGHT TO THE 1ST CTL SECTOR AND IT WAS AT THIS POINT THAT THE CTLR REMEMBERED THAT HE HAD NEVER CHANGED SMT Y'S FREQ TO THE NEW SECTOR. THE ERROR HAD JUST OCCURRED. THE 1ST SECTOR HAD TRNING IN PROGRESS WITH A 7 YR EXPERIENCED FPL AND THE 2ND SECTOR HAD A 7 YR EXPERIENCED FPL IN CTL. TFC WAS HEAVY IN BOTH SECTORS AT THE TIME OF THE INCIDENT. 2ND SECTOR COULD HAVE AND WOULD HAVE AVERTED THE INCIDENT;ERROR HAD A FREQ CHANGE BEEN ACCOMPLISHED AT AN APPROPRIATE TIME PRIOR TO SMT Y ENTERING THE 2ND SECTOR. ARTS HAND OFFS WERE INITIATED AND ACCEPTED TOO EARLY; RESULTING IN SMT Y BEING FORGOTTEN ABOUT BY BOTH SECTORS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING. RPTR WAS CHARGED WITH THE OP ERROR. NOTHING WAS SAID ABOUT THE FACT THAT THE LOSING CTLR HAD FAILED TO SEND THE SMT TO RPTR'S FREQ. WHEN THE TAG OF THE SMT DROPPED NEAR THE MAIN BANG OF THE RADAR; RPTR COMPLETELY FORGOT ABOUT THE ARTS HDOF HE HAD TAKEN SOME MINS BEFORE. THE ACFT PASSED WITHIN 400' VERT; AND 1500' HORIZ. TRNING WAS IN PROGRESS AT THE SECTOR WHERE THE FREQ CHANGE WAS NOT MADE.