Narrative:

Normal descent into cvg area. While on vectors at 8000 ft, we received a TCASII TA. Since we were in the clouds, we immediately looked for the traffic in the radar scope (autoplt on). We saw a return, ahead, level and closing in. A few seconds later, we received an RA, commanding a 2000 FPM descent. I disconnected the autoplt and immediately descended at 2000 FPM to 7500 ft. At this time, the RA ended. We climbed back to 8000 ft while notifying the controller. We did not know how close we were from the aircraft, but I feel that TCASII saved us.

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Original NASA ASRS Text

Title: TCASII RA CAUSES EVASION OF TFC CLOSING IN IMC.

Narrative: NORMAL DSCNT INTO CVG AREA. WHILE ON VECTORS AT 8000 FT, WE RECEIVED A TCASII TA. SINCE WE WERE IN THE CLOUDS, WE IMMEDIATELY LOOKED FOR THE TFC IN THE RADAR SCOPE (AUTOPLT ON). WE SAW A RETURN, AHEAD, LEVEL AND CLOSING IN. A FEW SECONDS LATER, WE RECEIVED AN RA, COMMANDING A 2000 FPM DSCNT. I DISCONNECTED THE AUTOPLT AND IMMEDIATELY DSNDED AT 2000 FPM TO 7500 FT. AT THIS TIME, THE RA ENDED. WE CLBED BACK TO 8000 FT WHILE NOTIFYING THE CTLR. WE DID NOT KNOW HOW CLOSE WE WERE FROM THE ACFT, BUT I FEEL THAT TCASII SAVED US.

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.