Narrative:

Our airline allows us to disregard the TCASII warnings/advisories if we have positive contact with the other aircraft. I think this is wrong. There are too many aircraft around. Who you see may not be who you hit! On approach to dfw we had what I think was a near midair collision with an air carrier Y 737 near love field. When we actually saw him he was approximately 500 ft below and 100 yards ahead. We were being vectored for a visual approach to runway 31, a last min change from downwind for runway 35. While descending we were advised of traffic which had us in sight and would level off below us. We saw traffic approximately 11 O'clock and 2-3 mi away, below us and diverging. We didn't consider him a problem, just another departure levelling off below us. Shortly we got a TCASII TA followed by an RA. We responded and pulled up but thinking that the earlier distant traffic caused the RA we were not overly concerned. When the advisory ceased we continued our descent and turned. About a min later we got another TA showing traffic directly below us. We stopped the descent and at that time saw air carrier Y below us and accelerating away on the same heading. I don't think he ever saw us. ATC told us later that air carrier Y said they had us in sight and were climbing visually.

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Original NASA ASRS Text

Title: FLC OF AN MLG DSNDING STOPPED AND PULLED UP IN RESPONSE TO A TCASII RA EVEN THOUGH ATC GAVE TA AND THE FLC HAD THE OTHER ACFT IN SIGHT.

Narrative: OUR AIRLINE ALLOWS US TO DISREGARD THE TCASII WARNINGS/ADVISORIES IF WE HAVE POSITIVE CONTACT WITH THE OTHER ACFT. I THINK THIS IS WRONG. THERE ARE TOO MANY ACFT AROUND. WHO YOU SEE MAY NOT BE WHO YOU HIT! ON APCH TO DFW WE HAD WHAT I THINK WAS A NEAR MIDAIR COLLISION WITH AN ACR Y 737 NEAR LOVE FIELD. WHEN WE ACTUALLY SAW HIM HE WAS APPROX 500 FT BELOW AND 100 YARDS AHEAD. WE WERE BEING VECTORED FOR A VISUAL APCH TO RWY 31, A LAST MIN CHANGE FROM DOWNWIND FOR RWY 35. WHILE DSNDING WE WERE ADVISED OF TFC WHICH HAD US IN SIGHT AND WOULD LEVEL OFF BELOW US. WE SAW TFC APPROX 11 O'CLOCK AND 2-3 MI AWAY, BELOW US AND DIVERGING. WE DIDN'T CONSIDER HIM A PROB, JUST ANOTHER DEP LEVELLING OFF BELOW US. SHORTLY WE GOT A TCASII TA FOLLOWED BY AN RA. WE RESPONDED AND PULLED UP BUT THINKING THAT THE EARLIER DISTANT TFC CAUSED THE RA WE WERE NOT OVERLY CONCERNED. WHEN THE ADVISORY CEASED WE CONTINUED OUR DSCNT AND TURNED. ABOUT A MIN LATER WE GOT ANOTHER TA SHOWING TFC DIRECTLY BELOW US. WE STOPPED THE DSCNT AND AT THAT TIME SAW ACR Y BELOW US AND ACCELERATING AWAY ON THE SAME HDG. I DON'T THINK HE EVER SAW US. ATC TOLD US LATER THAT ACR Y SAID THEY HAD US IN SIGHT AND WERE CLBING VISUALLY.

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.