Narrative:

We were level at 14000 ft on new york approach (126.8). New york cleared an air carrier Y B777 to climb from below us to 17000 ft in reference to us. Air carrier Y heavy said they had us in sight and on TCASII. We were flying northwest on the dpk 320 degree radial, air carrier Y was flying northeast. As they got closer, it was obvious they were on a collision course with us. I queried new york. In the meantime, our TCASII showed air carrier Y a mi or two to our left, within 1000 ft and closing. We got an RA to 'climb,' which we did at 2500 FPM. When air carrier Y passed under us, I believe they were around 600 ft below us. We climbed 700 ft above our assigned altitude before leveling. When I told new york what happened, he said 'he had you in sight, it was a triple seven, it probably just looked big.' air carrier Y never responded. I'm not sure what the air carrier Y pilots were thinking, they couldn't have been paying much attention. I believe if we hadn't taken evasive procedures, this would have been a midair collision.

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Original NASA ASRS Text

Title: FLC OF A BRITISH JETSTREAM, 41, CLBED IN RESPONSE TO A TCASII RA WHEN OBSERVING AN ACR B777 CLBING ON A COLLISION COURSE. DEP CTLR HAD ISSUED ADVISORY TO BOTH ACFT AND THE B777 CREW ADVISED THAT THE RPTR'S ACFT WAS IN SIGHT.

Narrative: WE WERE LEVEL AT 14000 FT ON NEW YORK APCH (126.8). NEW YORK CLRED AN ACR Y B777 TO CLB FROM BELOW US TO 17000 FT IN REF TO US. ACR Y HVY SAID THEY HAD US IN SIGHT AND ON TCASII. WE WERE FLYING NW ON THE DPK 320 DEG RADIAL, ACR Y WAS FLYING NE. AS THEY GOT CLOSER, IT WAS OBVIOUS THEY WERE ON A COLLISION COURSE WITH US. I QUERIED NEW YORK. IN THE MEANTIME, OUR TCASII SHOWED ACR Y A MI OR TWO TO OUR LEFT, WITHIN 1000 FT AND CLOSING. WE GOT AN RA TO 'CLB,' WHICH WE DID AT 2500 FPM. WHEN ACR Y PASSED UNDER US, I BELIEVE THEY WERE AROUND 600 FT BELOW US. WE CLBED 700 FT ABOVE OUR ASSIGNED ALT BEFORE LEVELING. WHEN I TOLD NEW YORK WHAT HAPPENED, HE SAID 'HE HAD YOU IN SIGHT, IT WAS A TRIPLE SEVEN, IT PROBABLY JUST LOOKED BIG.' ACR Y NEVER RESPONDED. I'M NOT SURE WHAT THE ACR Y PLTS WERE THINKING, THEY COULDN'T HAVE BEEN PAYING MUCH ATTN. I BELIEVE IF WE HADN'T TAKEN EVASIVE PROCS, THIS WOULD HAVE BEEN A MIDAIR COLLISION.

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.