Narrative:

During arrival at dfw from the northeast on the wilbr arrival, we were cleared for a visual approach to runway 17L. As we descended from 5000 ft to 3000 ft during a left turn to final, traffic was reported by regional approach control off our right side on approach to runway 17C. We observed that traffic and continued our left turn to intercept runway 17L final. As we continued our turn to final, the traffic fell behind our field of view. Approach handed us off to dfw tower. As we intercepted final, after changing to tower frequency but before contacting tower, the previously reported traffic caused our TCASII to give us a corrective RA requiring us to change from our descent to a climb. The traffic had moved from off our right side to behind and below us and was no longer visible. As we were occupied complying with the RA, dfw tower contacted us and advised us to climb due to a conflict with the aircraft below and behind us. We climbed to 3500 ft and the TCASII RA abated. I believe our closest approach to the other aircraft to have been, according to TCASII displayed information, 400 ft altitude separation and less than 1/2 mi lateral separation with the aircraft immediately behind and below us. At that time that traffic checked in with dfw tower and was cleared to land on runway 17L. We executed a missed approach by following tower instructions.

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Original NASA ASRS Text

Title: MD80 FLC FOLLOWS TCASII RA ON APCH TO RWY 17L AT DFW.

Narrative: DURING ARR AT DFW FROM THE NE ON THE WILBR ARR, WE WERE CLRED FOR A VISUAL APCH TO RWY 17L. AS WE DSNDED FROM 5000 FT TO 3000 FT DURING A L TURN TO FINAL, TFC WAS RPTED BY REGIONAL APCH CTL OFF OUR R SIDE ON APCH TO RWY 17C. WE OBSERVED THAT TFC AND CONTINUED OUR L TURN TO INTERCEPT RWY 17L FINAL. AS WE CONTINUED OUR TURN TO FINAL, THE TFC FELL BEHIND OUR FIELD OF VIEW. APCH HANDED US OFF TO DFW TWR. AS WE INTERCEPTED FINAL, AFTER CHANGING TO TWR FREQ BUT BEFORE CONTACTING TWR, THE PREVIOUSLY RPTED TFC CAUSED OUR TCASII TO GIVE US A CORRECTIVE RA REQUIRING US TO CHANGE FROM OUR DSCNT TO A CLB. THE TFC HAD MOVED FROM OFF OUR R SIDE TO BEHIND AND BELOW US AND WAS NO LONGER VISIBLE. AS WE WERE OCCUPIED COMPLYING WITH THE RA, DFW TWR CONTACTED US AND ADVISED US TO CLB DUE TO A CONFLICT WITH THE ACFT BELOW AND BEHIND US. WE CLBED TO 3500 FT AND THE TCASII RA ABATED. I BELIEVE OUR CLOSEST APCH TO THE OTHER ACFT TO HAVE BEEN, ACCORDING TO TCASII DISPLAYED INFO, 400 FT ALT SEPARATION AND LESS THAN 1/2 MI LATERAL SEPARATION WITH THE ACFT IMMEDIATELY BEHIND AND BELOW US. AT THAT TIME THAT TFC CHKED IN WITH DFW TWR AND WAS CLRED TO LAND ON RWY 17L. WE EXECUTED A MISSED APCH BY FOLLOWING TWR INSTRUCTIONS.

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.