Narrative:

Air carrier X descending into mht, was cleared to 7000 ft. Approach control said that we had traffic Y climbing to 6000 ft. I momentarily spotted the traffic at our 11 O'clock position on top of a cloud bank, I don't recall the distance. I soon lost sight of the traffic as it proceeded over an area clear of clouds. I never called the traffic in sight to approach control as visual contact was lost. We leveled at 7000 ft. Approach control radioed that our traffic had us in sight, would maintain visual separation, and was climbing out of 6000 ft. We were then cleared to 4000 ft. At approximately 6500 ft in the descent, I spotted our traffic at our 12 O'clock position, approximately 2 mi ahead, coming directly toward us in a right bank. Our TCASII was giving us a climb RA. With the traffic now in sight, the captain determined the safer course of action was to bank right and continue the descent. I immediately notified approach control that we were in the turn to avoid traffic. The traffic passed off our left wing, at our altitude, and in my estimation, was well within 1/2 mi of our aircraft. It would have been much closer had we not spotted the aircraft and made the turn.

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Original NASA ASRS Text

Title: VISUAL SEPARATION IN USE ACR X TCASII RA HAD CONFLICT WITH ACFT Y. EVASIVE ACTION TAKEN.

Narrative: ACR X DSNDING INTO MHT, WAS CLRED TO 7000 FT. APCH CTL SAID THAT WE HAD TFC Y CLBING TO 6000 FT. I MOMENTARILY SPOTTED THE TFC AT OUR 11 O'CLOCK POS ON TOP OF A CLOUD BANK, I DON'T RECALL THE DISTANCE. I SOON LOST SIGHT OF THE TFC AS IT PROCEEDED OVER AN AREA CLR OF CLOUDS. I NEVER CALLED THE TFC IN SIGHT TO APCH CTL AS VISUAL CONTACT WAS LOST. WE LEVELED AT 7000 FT. APCH CTL RADIOED THAT OUR TFC HAD US IN SIGHT, WOULD MAINTAIN VISUAL SEPARATION, AND WAS CLBING OUT OF 6000 FT. WE WERE THEN CLRED TO 4000 FT. AT APPROX 6500 FT IN THE DSCNT, I SPOTTED OUR TFC AT OUR 12 O'CLOCK POS, APPROX 2 MI AHEAD, COMING DIRECTLY TOWARD US IN A RIGHT BANK. OUR TCASII WAS GIVING US A CLB RA. WITH THE TFC NOW IN SIGHT, THE CAPT DETERMINED THE SAFER COURSE OF ACTION WAS TO BANK R AND CONTINUE THE DSCNT. I IMMEDIATELY NOTIFIED APCH CTL THAT WE WERE IN THE TURN TO AVOID TFC. THE TFC PASSED OFF OUR L WING, AT OUR ALT, AND IN MY ESTIMATION, WAS WELL WITHIN 1/2 MI OF OUR ACFT. IT WOULD HAVE BEEN MUCH CLOSER HAD WE NOT SPOTTED THE ACFT AND MADE THE TURN.

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.