Narrative:

With training commencing on radar west; I was working radar east; we were sharing the final approach to austin. Radar west was working aircraft X; an arrival from the northwest and was to be #1 arrival; I was working aircraft Y from the east and descending to 50 heading 300 degrees for sequence as #2 arrival. With both planes pointed at each other and waiting for radar west to turn aircraft X onto final and continue descent down to 30 for the visual approach to runway 17R; it came to my attention that aircraft X was no longer on frequency; NORDO. So; I took corrective action in telling radar west that I was turning aircraft Y in front and make this aircraft #1 for landing on runway 17R and for them not to turn the aircraft X back into traffic if he came back up on frequency. I then turned aircraft in for approach to avoid loss of separation. Immediately after that; I observed the aircraft X aircraft turning back to the airport and descending. With that; I immediately stopped aircraft Y descent and turned the aircraft right to a 350 degree heading; while explaining to him what just happened as to avoid further confusion. After investigation; aircraft X without direction inadvertently switched over to the tower frequency and told the tower controller they had the airport in sight. At this time the tower controller; who is not radar certified; issued a visual approach without control for turns from approach and then issued a landing clearance to aircraft X. Inadequate training/seasoning of the tower position at aus is partly to blame for this airspace deviation and could have led to a loss of separation.

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Original NASA ASRS Text

Title: AUS TRACON CTLR DESCRIBED CONFLICT EVENT AT 6000 WHEN ONE ACFT ON BASE CHANGED TO TWR; TWR CLRED ACFT FOR VISUAL; CONFLICTING WITH OTHER ACFT.

Narrative: WITH TRAINING COMMENCING ON RADAR W; I WAS WORKING RADAR E; WE WERE SHARING THE FINAL APCH TO AUSTIN. RADAR W WAS WORKING ACFT X; AN ARR FROM THE NW AND WAS TO BE #1 ARR; I WAS WORKING ACFT Y FROM THE E AND DSNDING TO 50 HDG 300 DEGS FOR SEQUENCE AS #2 ARR. WITH BOTH PLANES POINTED AT EACH OTHER AND WAITING FOR RADAR W TO TURN ACFT X ONTO FINAL AND CONTINUE DSCNT DOWN TO 30 FOR THE VISUAL APCH TO RWY 17R; IT CAME TO MY ATTN THAT ACFT X WAS NO LONGER ON FREQ; NORDO. SO; I TOOK CORRECTIVE ACTION IN TELLING RADAR W THAT I WAS TURNING ACFT Y IN FRONT AND MAKE THIS ACFT #1 FOR LNDG ON RWY 17R AND FOR THEM NOT TO TURN THE ACFT X BACK INTO TFC IF HE CAME BACK UP ON FREQ. I THEN TURNED ACFT IN FOR APCH TO AVOID LOSS OF SEPARATION. IMMEDIATELY AFTER THAT; I OBSERVED THE ACFT X ACFT TURNING BACK TO THE ARPT AND DSNDING. WITH THAT; I IMMEDIATELY STOPPED ACFT Y DSCNT AND TURNED THE ACFT R TO A 350 DEG HDG; WHILE EXPLAINING TO HIM WHAT JUST HAPPENED AS TO AVOID FURTHER CONFUSION. AFTER INVESTIGATION; ACFT X WITHOUT DIRECTION INADVERTENTLY SWITCHED OVER TO THE TWR FREQ AND TOLD THE TWR CTLR THEY HAD THE ARPT IN SIGHT. AT THIS TIME THE TWR CTLR; WHO IS NOT RADAR CERTIFIED; ISSUED A VISUAL APCH WITHOUT CTL FOR TURNS FROM APCH AND THEN ISSUED A LNDG CLRNC TO ACFT X. INADEQUATE TRAINING/SEASONING OF THE TWR POS AT AUS IS PARTLY TO BLAME FOR THIS AIRSPACE DEV AND COULD HAVE LED TO A LOSS OF SEPARATION.

Data retrieved from NASA's ASRS site as of May 2009 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.