Narrative:

While in cruise, approach asked us if we had traffic lower and ahead in sight. This aircraft was not in communication with ATC. We acknowledged that we did. The traffic was slower than us and appeared that it was in a slow, steady climb. About 10 mins later, we received a TA from the subject traffic. Because we still had it in sight, we turned the TCASII mode to 'TA only.' moments later the traffic seemed to be converging with us and level. I instructed my first officer to bank left immediately, as we safely passed the traffic. At the same time approach asked us to verify that we still had the traffic in sight. I acknowledged with 'affirmative, we are in a left turn.' he replied with 'roger, proceed direct madison VOR when able.' we were handed off without incident. A good lesson was learned in that when maintaining visual separation, especially at night, extreme caution should be exercised. In addition, because the RA function was off, our visual cues were our only defense. The traffic crept up on us because they were climbing so slow, and we should have kept a better watch on it.

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Original NASA ASRS Text

Title: IN NIGHTTIME CONDITIONS, AN LTT ACR CREW ADVISED BDL APCH THEY HAD UNKNOWN VFR TFC AHEAD IN SIGHT. A SHORT TIME LATER THE CREW TOOK EVASIVE ACTION TO PASS AND AVOID THE TFC/

Narrative: WHILE IN CRUISE, APCH ASKED US IF WE HAD TFC LOWER AND AHEAD IN SIGHT. THIS ACFT WAS NOT IN COM WITH ATC. WE ACKNOWLEDGED THAT WE DID. THE TFC WAS SLOWER THAN US AND APPEARED THAT IT WAS IN A SLOW, STEADY CLB. ABOUT 10 MINS LATER, WE RECEIVED A TA FROM THE SUBJECT TFC. BECAUSE WE STILL HAD IT IN SIGHT, WE TURNED THE TCASII MODE TO 'TA ONLY.' MOMENTS LATER THE TFC SEEMED TO BE CONVERGING WITH US AND LEVEL. I INSTRUCTED MY FO TO BANK L IMMEDIATELY, AS WE SAFELY PASSED THE TFC. AT THE SAME TIME APCH ASKED US TO VERIFY THAT WE STILL HAD THE TFC IN SIGHT. I ACKNOWLEDGED WITH 'AFFIRMATIVE, WE ARE IN A L TURN.' HE REPLIED WITH 'ROGER, PROCEED DIRECT MADISON VOR WHEN ABLE.' WE WERE HANDED OFF WITHOUT INCIDENT. A GOOD LESSON WAS LEARNED IN THAT WHEN MAINTAINING VISUAL SEPARATION, ESPECIALLY AT NIGHT, EXTREME CAUTION SHOULD BE EXERCISED. IN ADDITION, BECAUSE THE RA FUNCTION WAS OFF, OUR VISUAL CUES WERE OUR ONLY DEFENSE. THE TFC CREPT UP ON US BECAUSE THEY WERE CLBING SO SLOW, AND WE SHOULD HAVE KEPT A BETTER WATCH ON IT.

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.