Narrative:

Ny approach vectored us from rymes intersection south to shoreline for vus to runway 34 at hpn. Vectored us at 3000' MSL to westerly heading along shoreline to final visibility behind straight-in traffic. Both first officer and I located what we believed to be the traffic advised although first officer called it out as 12 O'clock when it was actually closer to 2 O'clock on its final approach to hpn runway 34. Ny cleared us visibility behind the traffic contact hpn tower. I started out of 3000' and a right turn in to intercept localizer adn G/south slowing to sequence on the traffic. First officer called tower who asked if we had small transport jet at 11 O'clock and 1/4 mi that we were to follow. He was on localizer G/south and I was on trajectory to intercept him right about at OM. I pulled power off, nose up perhaps 5 degree climb and left turn 20 degree bank to pass behind him. I do not believe he made any evasive maneuver although he saw us and was probably nervous and mad. If first officer had properly called the preceeding aircraft that we mistook for him as 2 O'clock instead of 12 O'clock, ny might have realized we had the wrong one. Frequency congestion let me let it go. Next time I won't. Other than that I feel this is a problem with visuals to follow traffic that is very hard to identify. Probably will happen again and not much we can do about it. This is the second closest I've ever been. Although the evasion was gentle, the trajectory would have been nearly perfect. It would have been bad.

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Original NASA ASRS Text

Title: PLT OF LTT ACCEPTED VISUAL AFTER IDENTIFYING HIS TRAFFIC. TURNING TO FINAL, TWR QUERRIED IF HE AHD HIS TRAFFIC. FLT CREW OF LTT THEN SAW THE TRAFFIC THEY WERE SUPPOSED TO FOLLOW ON AN INTERCEPT TRAJECTORY. FLT CREW TOOK MILD EVASIVE ACTION TO INTERCEPT THE LOC AND GLIDE SLOPE BEHIND THE JET TRAFFIC. FO HAD IDENTIFIED WRONG TRAFFIC FROM APCH CTLR POINT OUT.

Narrative: NY APCH VECTORED US FROM RYMES INTXN S TO SHORELINE FOR VUS TO RWY 34 AT HPN. VECTORED US AT 3000' MSL TO WESTERLY HDG ALONG SHORELINE TO FINAL VIS BEHIND STRAIGHT-IN TFC. BOTH F/O AND I LOCATED WHAT WE BELIEVED TO BE THE TFC ADVISED ALTHOUGH F/O CALLED IT OUT AS 12 O'CLOCK WHEN IT WAS ACTUALLY CLOSER TO 2 O'CLOCK ON ITS FINAL APCH TO HPN RWY 34. NY CLRED US VIS BEHIND THE TFC CONTACT HPN TWR. I STARTED OUT OF 3000' AND A R TURN IN TO INTERCEPT LOC ADN G/S SLOWING TO SEQUENCE ON THE TFC. F/O CALLED TWR WHO ASKED IF WE HAD SMT JET AT 11 O'CLOCK AND 1/4 MI THAT WE WERE TO FOLLOW. HE WAS ON LOC G/S AND I WAS ON TRAJECTORY TO INTERCEPT HIM R ABOUT AT OM. I PULLED PWR OFF, NOSE UP PERHAPS 5 DEG CLB AND L TURN 20 DEG BANK TO PASS BEHIND HIM. I DO NOT BELIEVE HE MADE ANY EVASIVE MANEUVER ALTHOUGH HE SAW US AND WAS PROBABLY NERVOUS AND MAD. IF F/O HAD PROPERLY CALLED THE PRECEEDING ACFT THAT WE MISTOOK FOR HIM AS 2 O'CLOCK INSTEAD OF 12 O'CLOCK, NY MIGHT HAVE REALIZED WE HAD THE WRONG ONE. FREQ CONGESTION LET ME LET IT GO. NEXT TIME I WON'T. OTHER THAN THAT I FEEL THIS IS A PROB WITH VISUALS TO FOLLOW TFC THAT IS VERY HARD TO IDENT. PROBABLY WILL HAPPEN AGAIN AND NOT MUCH WE CAN DO ABOUT IT. THIS IS THE SEC CLOSEST I'VE EVER BEEN. ALTHOUGH THE EVASION WAS GENTLE, THE TRAJECTORY WOULD HAVE BEEN NEARLY PERFECT. IT WOULD HAVE BEEN BAD.

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.