Narrative:

We were being vectored for an ILS runway 36L approximately 20 mi southwest of dfw at 5000 ft, 170 KTS assigned, flaps 11 degrees. Controller was very busy and there was significant frequency congestion. At 5000 ft we were in the clear with a cloud deck at approximately 4000 ft MSL under us. I was the captain and I visually could see another aircraft at 11 O'clock and about 5-6 mi at approximately our altitude. Controller, a few seconds later, instructed us to turn to 030 degrees and hustle down to 4000 ft. The first officer was flying and also had aircraft in sight. At about 4600 ft MSL, descending to 4000 ft, we got a TCASII RA which first said climb and a few seconds later said climb crossing climb. I told the first officer to continue the descent per ATC. No evasive maneuvers were taken. I announced on frequency 127.07 that we had an RA and we were doing the opposite of the commands in frequency congestion. Had we climbed per the TCASII there is no doubt in my mind we would have hit the other aircraft. We missed 500-600 ft vertically and less than 1/2 mi horizontally. The other aircraft, a company MD80 at 5000 ft sbound, did not alter course or altitude. At 4000 ft we were in and out of the tops of the clouds. Continued to an uneventful landing.

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Original NASA ASRS Text

Title: MD80S ACFT BEING VECTORED FOR ILS APCH. FLC SAW ANOTHER ACFT WHICH WAS POTENTIAL CONFLICT WHEN APCH CTLR GAVE A HDG AND ALT CLRNC, APPARENTLY TO AVOID THE TFC. FLC RECEIVED A TCASII RA, BUT IGNORED IT DUE TO THE VISUAL ON THE TFC. RPTR CAPT BELIEVES THAT THE TCASII COMMANDS WOULD HAVE CAUSED A MIDAIR WITH THE SUBJECT TFC.

Narrative: WE WERE BEING VECTORED FOR AN ILS RWY 36L APPROX 20 MI SW OF DFW AT 5000 FT, 170 KTS ASSIGNED, FLAPS 11 DEGS. CTLR WAS VERY BUSY AND THERE WAS SIGNIFICANT FREQ CONGESTION. AT 5000 FT WE WERE IN THE CLR WITH A CLOUD DECK AT APPROX 4000 FT MSL UNDER US. I WAS THE CAPT AND I VISUALLY COULD SEE ANOTHER ACFT AT 11 O'CLOCK AND ABOUT 5-6 MI AT APPROX OUR ALT. CTLR, A FEW SECONDS LATER, INSTRUCTED US TO TURN TO 030 DEGS AND HUSTLE DOWN TO 4000 FT. THE FO WAS FLYING AND ALSO HAD ACFT IN SIGHT. AT ABOUT 4600 FT MSL, DSNDING TO 4000 FT, WE GOT A TCASII RA WHICH FIRST SAID CLB AND A FEW SECONDS LATER SAID CLB XING CLB. I TOLD THE FO TO CONTINUE THE DSCNT PER ATC. NO EVASIVE MANEUVERS WERE TAKEN. I ANNOUNCED ON FREQ 127.07 THAT WE HAD AN RA AND WE WERE DOING THE OPPOSITE OF THE COMMANDS IN FREQ CONGESTION. HAD WE CLBED PER THE TCASII THERE IS NO DOUBT IN MY MIND WE WOULD HAVE HIT THE OTHER ACFT. WE MISSED 500-600 FT VERTLY AND LESS THAN 1/2 MI HORIZLY. THE OTHER ACFT, A COMPANY MD80 AT 5000 FT SBOUND, DID NOT ALTER COURSE OR ALT. AT 4000 FT WE WERE IN AND OUT OF THE TOPS OF THE CLOUDS. CONTINUED TO AN UNEVENTFUL LNDG.

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.