Narrative:

I was the PF (pilot flying) conducting a visual approach to runway 10 at tvc. After a go around due to wind shear; we received a TCAS descending RA (resolution advisory) while being vectored onto the left downwind at 3000 ft. The autopilot was engaged and my aircraft had just rolled out on an assigned heading of 270 degrees. My airspeed was 200 kts. The traffic of conflict appeared to be operating under VFR. Upon initial indication of the TA (traffic advisory); the aircraft appeared to be at my 11 o'clock position; less than one mile; and showing an altitude of +100 above us. Within a few seconds; it was obvious to me that our aircraft were on a collision course. The TA almost immediately changed to an RA commanding an initial descent rate of 1000-1200 fpm. It was about this time that ATC first contacted us about the traffic. I promptly followed the guidance of the RA; which by now was commanding a descent of approximately 1800-2000 fpm. I maintained visual contact with the conflicting traffic; while dividing my attention with the RA guidance. The aircraft appeared to be in a descending right turn. The aircraft passed nearly overhead; and perhaps only slightly to my left; at an altitude above us I would estimate to be 300-400 ft. Shortly after passing the traffic; we received the 'clear of conflict' aural. I leveled the aircraft at 2500 ft and we received clearance for a visual approach to runway 10. Two aircraft in very close proximity.

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Original NASA ASRS Text

Title: Air carrier Captain reported a NMAC with traffic not called by ATC.

Narrative: I was the PF (Pilot Flying) conducting a visual approach to Runway 10 at TVC. After a go around due to wind shear; we received a TCAS descending RA (Resolution Advisory) while being vectored onto the left downwind at 3000 ft. The autopilot was engaged and my aircraft had just rolled out on an assigned heading of 270 degrees. My airspeed was 200 kts. The traffic of conflict appeared to be operating under VFR. Upon initial indication of the TA (Traffic Advisory); the aircraft appeared to be at my 11 o'clock position; less than one mile; and showing an altitude of +100 above us. Within a few seconds; it was obvious to me that our aircraft were on a collision course. The TA almost immediately changed to an RA commanding an initial descent rate of 1000-1200 fpm. It was about this time that ATC first contacted us about the traffic. I promptly followed the guidance of the RA; which by now was commanding a descent of approximately 1800-2000 fpm. I maintained visual contact with the conflicting traffic; while dividing my attention with the RA guidance. The aircraft appeared to be in a descending right turn. The aircraft passed nearly overhead; and perhaps only slightly to my left; at an altitude above us I would estimate to be 300-400 ft. Shortly after passing the traffic; we received the 'clear of conflict' aural. I leveled the aircraft at 2500 ft and we received clearance for a visual approach to Runway 10. Two aircraft in very close proximity.

Data retrieved from NASA's ASRS site 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.