Narrative:

Small aircraft X was on NDB runway 27 approach to bjj, and small aircraft Y departed cak after practice approachs, and was en route to 22G. Small aircraft X was outbnd for procedure turn, and small aircraft Y on vectors. Heading 280 degrees, to join V40 to ritzs intersection. I was training an ATC developmental on approach, and pointed out to this trnee the potential for conflict due to the direction of procedure turn, while these aircraft were about 15 mi apart. I let this situation develop as far as possible west/O intervention, to allow the developmental controller an opportunity to separate these aircraft. The trnee's vector, heading 320 degrees for small aircraft Y, was not enough to ensure sep. I intervened when there was about 4 mi sep. I broke small aircraft X off of the approach with a clearance to maintain 3000' and turn left heading 270 degrees. The pilot did not respond. I turned the small aircraft Y to heading 360 degrees and immediately reissued the turn clearance to small aircraft X. Small aircraft X responded by saying, 'we're on procedure turn for approach,' and still did not turn left. I then told small aircraft X to 'turn left immediately, heading 270 degrees, traffic 1 O'clock 3 mi, an small aircraft at 3000.' I turned small aircraft Y further to heading 050 degrees. At the closest point I had 2 mi between these aircraft where 3 mi was required. This sep error occurred due to the pilot's failure to turn when issued a clearance. A contributing factor was my allowing this situation to develop into an urgent situation requiring prompt resolution. Had the pilot of small aircraft X turned after the first clearance, 3 mi sep would have been maintained.

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Original NASA ASRS Text

Title: SMA CAME IN CLOSE PROX TO ANOTHER ACFT WHILE ON A RADAR VECTOR.

Narrative: SMA X WAS ON NDB RWY 27 APCH TO BJJ, AND SMA Y DEPARTED CAK AFTER PRACTICE APCHS, AND WAS ENRTE TO 22G. SMA X WAS OUTBND FOR PROC TURN, AND SMA Y ON VECTORS. HDG 280 DEGS, TO JOIN V40 TO RITZS INTXN. I WAS TRNING AN ATC DEVELOPMENTAL ON APCH, AND POINTED OUT TO THIS TRNEE THE POTENTIAL FOR CONFLICT DUE TO THE DIRECTION OF PROC TURN, WHILE THESE ACFT WERE ABOUT 15 MI APART. I LET THIS SITUATION DEVELOP AS FAR AS POSSIBLE W/O INTERVENTION, TO ALLOW THE DEVELOPMENTAL CTLR AN OPPORTUNITY TO SEPARATE THESE ACFT. THE TRNEE'S VECTOR, HDG 320 DEGS FOR SMA Y, WAS NOT ENOUGH TO ENSURE SEP. I INTERVENED WHEN THERE WAS ABOUT 4 MI SEP. I BROKE SMA X OFF OF THE APCH WITH A CLRNC TO MAINTAIN 3000' AND TURN LEFT HDG 270 DEGS. THE PLT DID NOT RESPOND. I TURNED THE SMA Y TO HDG 360 DEGS AND IMMEDIATELY REISSUED THE TURN CLRNC TO SMA X. SMA X RESPONDED BY SAYING, 'WE'RE ON PROC TURN FOR APCH,' AND STILL DID NOT TURN LEFT. I THEN TOLD SMA X TO 'TURN LEFT IMMEDIATELY, HDG 270 DEGS, TFC 1 O'CLOCK 3 MI, AN SMA AT 3000.' I TURNED SMA Y FURTHER TO HDG 050 DEGS. AT THE CLOSEST POINT I HAD 2 MI BTWN THESE ACFT WHERE 3 MI WAS REQUIRED. THIS SEP ERROR OCCURRED DUE TO THE PLT'S FAILURE TO TURN WHEN ISSUED A CLRNC. A CONTRIBUTING FACTOR WAS MY ALLOWING THIS SITUATION TO DEVELOP INTO AN URGENT SITUATION REQUIRING PROMPT RESOLUTION. HAD THE PLT OF SMA X TURNED AFTER THE FIRST CLRNC, 3 MI SEP WOULD HAVE BEEN MAINTAINED.

Data retrieved from NASA's ASRS site as of August 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.