Narrative:

Air carrier X from boston to portland, me. We were flying direct pease VOR at 7000 ft when ATC told us traffic 12 O'clock 5 mi at 7700 ft. We told ATC 'negative traffic. Keep us advised.' 'traffic' then called ATC 'traffic in sight.' next transmission from ATC sounded like, 'traffic will pass behind.' then traffic passed in front of us from 3 O'clock at the same altitude and missed us by approximately 500 ft. We told ATC we had traffic passing by. ATC told us that he had given us a heading for traffic and the traffic had us in sight. We never heard ATC call for a heading, or did we read it back. I believe that the traffic should have kept much greater distance and ATC should have listened for a readback. Plus a TCASII would have been helpful.

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Original NASA ASRS Text

Title: ACR X HAD NMAC WITH ACR BE02. VISUAL SEPARATION IN USE. SEE AND AVOID CONCEPT.

Narrative: ACR X FROM BOSTON TO PORTLAND, ME. WE WERE FLYING DIRECT PEASE VOR AT 7000 FT WHEN ATC TOLD US TFC 12 O'CLOCK 5 MI AT 7700 FT. WE TOLD ATC 'NEGATIVE TFC. KEEP US ADVISED.' 'TFC' THEN CALLED ATC 'TFC IN SIGHT.' NEXT XMISSION FROM ATC SOUNDED LIKE, 'TFC WILL PASS BEHIND.' THEN TFC PASSED IN FRONT OF US FROM 3 O'CLOCK AT THE SAME ALT AND MISSED US BY APPROX 500 FT. WE TOLD ATC WE HAD TFC PASSING BY. ATC TOLD US THAT HE HAD GIVEN US A HDG FOR TFC AND THE TFC HAD US IN SIGHT. WE NEVER HEARD ATC CALL FOR A HDG, OR DID WE READ IT BACK. I BELIEVE THAT THE TFC SHOULD HAVE KEPT MUCH GREATER DISTANCE AND ATC SHOULD HAVE LISTENED FOR A READBACK. PLUS A TCASII WOULD HAVE BEEN HELPFUL.

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.