LFT NOTIFIED ZHU OF DUPLICATE BEACON CODE OF DEPARTING E145. ZHU DETERMINES CALL SIGN STILL IN USE FROM ENRTE COMPANY E145.

Narrative

LFT DEP CALLED TO ADVISE ACR XXX HAD DEPARTED LFT; BUT THEY COULD NOT DEPART HIM IN THE COMPUTER TO ACTIVATE FLT PLAN. I TOOK RADAR CONTACT AND THEN DID A FLT PLAN READOUT ON ACR XXX AND DISCOVERED ACR XXX WAS ALREADY BEING USED BY A FLT FROM IAH TO SLW. I THEN AMENDED THE LFT ACR XXX TO ACR XX AND DEPARTED THE ACFT AND STARTED A TRACK ON THIS ACFT. THIS IS THE THIRD TIME THIS EXACT SIT HAS OCCURRED TO ME PERSONALLY. THE FIRST TIME WAS ABOUT 6 MONTHS AGO. THE SECOND 2 WKS AGO; AND THEN AGAIN NOW. I HAVE TALKED WITH OTHER CTLRS WHO HAVE HAD THIS SAME SIT ALSO. ONE OCCURRENCE RESULTED IN A SYS DEV AS THE FLT PLAN FOR THE ACTIVE ACFT WAS REMOVED FROM THE SYS SO THE OTHER FLT PLAN COULD BE ACTIVATED. THIS ACTION RESULTED IN THE DATA BLOCK BEING DROPPED FROM THE SCOPE OF THE CTLR AND THE ACFT VIOLATED THE AIRSPACE OF THE NEXT SECTOR. EACH TIME THIS SIT HAS OCCURRED; THE AIRLINES SAY THEIR DISPATCHER IS SUPPOSED TO AMEND THE CALL SIGN OF THE ACFT THAT IS ABOUT TO DEPART; BUT THIS REQUIRES A MANUAL CHANGE BE INPUT INTO THE COMPUTER SYS. THIS PROC HAS FAILED 3 TIMES. MY RECOMMENDATION TO RESOLVE THIS SIT IS VERY SIMPLE -- ON CONNECTING FLTS; IF YOU CHANGE AIRPLANES; YOU CHANGE CALL SIGNS. WITH ALL THE NUMBERS AVAILABLE TO THE ACRS; THIS SHOULD NOT BE A MAJOR FIX.