Narrative:

On arrival into okc, approach cleared us to descend to 4000 ft and fly direct to gally OM for the visual to runway 35R. At this time we were approximately 20 DME sse of irw VOR, descending out of 6000 ft for 4000 ft. Numerous VFR targets began appearing on TCASII 3000-2500 ft below us. At 4500 ft descending to 4000 ft, approach called traffic at our 12 O'clock, 3500 ft and climbing. Simultaneously we got a TCASII TA on that traffic. I told the copilot to level off at 4300 ft and climb back to 4500 ft. As he began to level off at 4300 ft, TCASII issued an RA 'descend, descend' followed almost immediately by a 'climb, climb' which the copilot immediately responded to. We never saw the traffic visually but TCASII indicated 500 ft separation. FAA inspector was on the jump seat conducting a check at the time.

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Original NASA ASRS Text

Title: FLC OF AN MLG STOPPED DSCNT IN RESPONSE TO A TCASII RA. NMAC.

Narrative: ON ARR INTO OKC, APCH CLRED US TO DSND TO 4000 FT AND FLY DIRECT TO GALLY OM FOR THE VISUAL TO RWY 35R. AT THIS TIME WE WERE APPROX 20 DME SSE OF IRW VOR, DSNDING OUT OF 6000 FT FOR 4000 FT. NUMEROUS VFR TARGETS BEGAN APPEARING ON TCASII 3000-2500 FT BELOW US. AT 4500 FT DSNDING TO 4000 FT, APCH CALLED TFC AT OUR 12 O'CLOCK, 3500 FT AND CLBING. SIMULTANEOUSLY WE GOT A TCASII TA ON THAT TFC. I TOLD THE COPLT TO LEVEL OFF AT 4300 FT AND CLB BACK TO 4500 FT. AS HE BEGAN TO LEVEL OFF AT 4300 FT, TCASII ISSUED AN RA 'DSND, DSND' FOLLOWED ALMOST IMMEDIATELY BY A 'CLB, CLB' WHICH THE COPLT IMMEDIATELY RESPONDED TO. WE NEVER SAW THE TFC VISUALLY BUT TCASII INDICATED 500 FT SEPARATION. FAA INSPECTOR WAS ON THE JUMP SEAT CONDUCTING A CHK AT THE TIME.

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.