Narrative:

On the cqy arrival, was given the ATC instruction turn left to heading 180 degrees. As I, the captain and the PF, reached for the heading select knob on the fmp, the controller again called and said immediately turn to 180 degrees. My first inclination was 'loss of separation' and during the heading change I visually acquired and TCASII acquired a target at 12 O'clock less than 10 NM, crossing left to right. It appeared to be an MD80 but I'm not sure. The controller then issued a descent for my aircraft and a climb for the other. As the target closed to about 5 NM, TCASII issued a TA but not an RA. At that point we were obtaining some vertical separation, as well. My first officer queried ZFW about the possible loss of separation several times, and was given a phone number to contact. Also, at this time, a controller of a distinguishably different voice assumed control of our flight. Shortly thereafter, we rejoined the arrival, received a frequency change, and continued to dfw without further incident. Upon arrival, I contacted the phone number given and was told that they were all in a meeting playing back the tapes. I was subsequently given a different phone number to contact the area manager. However, the meeting continued, and I was never able to discuss the matter. My summation is that there was a loss of separation, although the controller caught the impending disaster and rectified it with a heading change. With my nd set at 240, traffic wasn't noticed early.

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Original NASA ASRS Text

Title: RPTR CLAIMS A POSSIBLE LOSS OF SEPARATION WITH ANOTHER ACR AT THE SAME ALT.

Narrative: ON THE CQY ARR, WAS GIVEN THE ATC INSTRUCTION TURN L TO HDG 180 DEGS. AS I, THE CAPT AND THE PF, REACHED FOR THE HDG SELECT KNOB ON THE FMP, THE CTLR AGAIN CALLED AND SAID IMMEDIATELY TURN TO 180 DEGS. MY FIRST INCLINATION WAS 'LOSS OF SEPARATION' AND DURING THE HDG CHANGE I VISUALLY ACQUIRED AND TCASII ACQUIRED A TARGET AT 12 O'CLOCK LESS THAN 10 NM, XING L TO R. IT APPEARED TO BE AN MD80 BUT I'M NOT SURE. THE CTLR THEN ISSUED A DSCNT FOR MY ACFT AND A CLB FOR THE OTHER. AS THE TARGET CLOSED TO ABOUT 5 NM, TCASII ISSUED A TA BUT NOT AN RA. AT THAT POINT WE WERE OBTAINING SOME VERT SEPARATION, AS WELL. MY FO QUERIED ZFW ABOUT THE POSSIBLE LOSS OF SEPARATION SEVERAL TIMES, AND WAS GIVEN A PHONE NUMBER TO CONTACT. ALSO, AT THIS TIME, A CTLR OF A DISTINGUISHABLY DIFFERENT VOICE ASSUMED CTL OF OUR FLT. SHORTLY THEREAFTER, WE REJOINED THE ARR, RECEIVED A FREQ CHANGE, AND CONTINUED TO DFW WITHOUT FURTHER INCIDENT. UPON ARR, I CONTACTED THE PHONE NUMBER GIVEN AND WAS TOLD THAT THEY WERE ALL IN A MEETING PLAYING BACK THE TAPES. I WAS SUBSEQUENTLY GIVEN A DIFFERENT PHONE NUMBER TO CONTACT THE AREA MGR. HOWEVER, THE MEETING CONTINUED, AND I WAS NEVER ABLE TO DISCUSS THE MATTER. MY SUMMATION IS THAT THERE WAS A LOSS OF SEPARATION, ALTHOUGH THE CTLR CAUGHT THE IMPENDING DISASTER AND RECTIFIED IT WITH A HDG CHANGE. WITH MY ND SET AT 240, TFC WASN'T NOTICED EARLY.

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.