Narrative:

Just leveled off and switched to ZNY at 10000 ft. Simultaneously, while checking with ZNY, I noticed a target on our TCASII. It ws at our altitude at 5 mi and was yellow. I assumed it was going the same way as us since it was at our altitude. Almost immediately, ZNY gave us a climb to 13000 ft. At this time I noticed the target was coming at us, and we got a TA as I read back the clearance. The target aircraft passed directly under us somewhere between 200-600 ft. To my knowledge we were never advised of the traffic. We did not get an RA.

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Original NASA ASRS Text

Title: MD80 AND CONFLICTING ACFT HAD TCASII TA IN ZNY CLASS E AIRSPACE.

Narrative: JUST LEVELED OFF AND SWITCHED TO ZNY AT 10000 FT. SIMULTANEOUSLY, WHILE CHKING WITH ZNY, I NOTICED A TARGET ON OUR TCASII. IT WS AT OUR ALT AT 5 MI AND WAS YELLOW. I ASSUMED IT WAS GOING THE SAME WAY AS US SINCE IT WAS AT OUR ALT. ALMOST IMMEDIATELY, ZNY GAVE US A CLB TO 13000 FT. AT THIS TIME I NOTICED THE TARGET WAS COMING AT US, AND WE GOT A TA AS I READ BACK THE CLRNC. THE TARGET ACFT PASSED DIRECTLY UNDER US SOMEWHERE BTWN 200-600 FT. TO MY KNOWLEDGE WE WERE NEVER ADVISED OF THE TFC. WE DID NOT GET AN RA.

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.