Narrative:

Atx X on a 3 mi left base for runway 13L. Had been issued landing clearance. Aircraft speed approximately 100 KTS, altitude 2000' (descending), on VFR flight plan/clearance. Air carrier Y 2 mi north established on left downwind, altitude 2000'. Not in communication with love tower, IFR. I observed the air carrier Y begin a turn to base leg and start descending out of 2000'. I immediately issued a turn to the west to atx X. No response. I reissued the immediate turn to the west to atx X. I observed atx X begin the turn toward the west. Call #3 was to alert him again. The approach controller was screaming over the landline that air carrier Y had the wrong aircraft in sight. I assumed that they had issued traffic for him to follow and he picked out the lights of an aircraft in the distance, not the closer (correct) one. My third and final transmission to atx X was one of an impending/existing traffic conflict. The slower turning atx small aircraft had already barely began the westbound turn. The aircraft were at the same altitude (1700'), both descending to land and closing rapidly. I believe they were 1/4-1/2 mi apart (or closer). Air carrier Y called up and was issued landing clearance. Atx X was established westbound. It was over. The pilot of atx X apologized for not answering my instructions and stated that he was just too busy trying to get the aircraft out of the way of the closing air carrier Y.

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Original NASA ASRS Text

Title: APCH CTL GAVE LATE FREQ CHANGE TO ACR Y CAUSING TRAFFIC PATTERN CONFLICT. OPERATIONAL DEVIATION. SEE AND AVOID CONCEPT.

Narrative: ATX X ON A 3 MI LEFT BASE FOR RWY 13L. HAD BEEN ISSUED LNDG CLRNC. ACFT SPD APPROX 100 KTS, ALT 2000' (DSNDING), ON VFR FLT PLAN/CLRNC. ACR Y 2 MI N ESTABLISHED ON LEFT DOWNWIND, ALT 2000'. NOT IN COM WITH LOVE TWR, IFR. I OBSERVED THE ACR Y BEGIN A TURN TO BASE LEG AND START DSNDING OUT OF 2000'. I IMMEDIATELY ISSUED A TURN TO THE W TO ATX X. NO RESPONSE. I REISSUED THE IMMEDIATE TURN TO THE W TO ATX X. I OBSERVED ATX X BEGIN THE TURN TOWARD THE W. CALL #3 WAS TO ALERT HIM AGAIN. THE APCH CTLR WAS SCREAMING OVER THE LANDLINE THAT ACR Y HAD THE WRONG ACFT IN SIGHT. I ASSUMED THAT THEY HAD ISSUED TFC FOR HIM TO FOLLOW AND HE PICKED OUT THE LIGHTS OF AN ACFT IN THE DISTANCE, NOT THE CLOSER (CORRECT) ONE. MY THIRD AND FINAL XMISSION TO ATX X WAS ONE OF AN IMPENDING/EXISTING TFC CONFLICT. THE SLOWER TURNING ATX SMA HAD ALREADY BARELY BEGAN THE WBND TURN. THE ACFT WERE AT THE SAME ALT (1700'), BOTH DSNDING TO LAND AND CLOSING RAPIDLY. I BELIEVE THEY WERE 1/4-1/2 MI APART (OR CLOSER). ACR Y CALLED UP AND WAS ISSUED LNDG CLRNC. ATX X WAS ESTABLISHED WBND. IT WAS OVER. THE PLT OF ATX X APOLOGIZED FOR NOT ANSWERING MY INSTRUCTIONS AND STATED THAT HE WAS JUST TOO BUSY TRYING TO GET THE ACFT OUT OF THE WAY OF THE CLOSING ACR Y.

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.