Narrative:

Departing ewr level 12000 ft, working nyc TRACON, I was given traffic at 15000 ft. ATC offered a climb to 17000 ft if we could maintain visual separation with that traffic. I saw traffic at 11 O'clock moving left. Then was able to get the 2 O'clock traffic visually and on TCASII. For reasons I'm not sure of, I had it in my mind that the traffic was going in the same direction and we would be passing several miles off their left side and through their altitude. Later when the first officer and I were discussing the incident neither of us could remember the controller issuing a direction of travel or saying anything like crossing traffic, etc. Since I didn't consider the traffic a threat, I asked the first officer (who was the handling pilot) if he understood the clearance and had the traffic. He replied in the affirmative. I reached down to pick up some charts that had fallen on the floor during some turbulence. While I was heads down, the TCASII sounded a TA. I looked up to see the traffic was crossing right to left and we were going to pass very close. All at about the same instant we got an RA, I was prompting the copilot to take action and the controller was questioning what we were doing. We passed about 2 mi in front and 500 ft below the commuter plane. The commuter flight felt the distance was more like 1 mi. I was too busy trying to keep a visual contact to notice the distance on the navigation display. After we were clear of conflict, I asked the first officer why he didn't watch the traffic a little closer. He said he thought the traffic we had initially seen at 11 O'clock was the traffic in question and we were passing behind them.

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Original NASA ASRS Text

Title: B777 CREW HAD TCASII RA IN N90 CLASS E AIRSPACE.

Narrative: DEPARTING EWR LEVEL 12000 FT, WORKING NYC TRACON, I WAS GIVEN TFC AT 15000 FT. ATC OFFERED A CLB TO 17000 FT IF WE COULD MAINTAIN VISUAL SEPARATION WITH THAT TFC. I SAW TFC AT 11 O'CLOCK MOVING L. THEN WAS ABLE TO GET THE 2 O'CLOCK TFC VISUALLY AND ON TCASII. FOR REASONS I'M NOT SURE OF, I HAD IT IN MY MIND THAT THE TFC WAS GOING IN THE SAME DIRECTION AND WE WOULD BE PASSING SEVERAL MILES OFF THEIR L SIDE AND THROUGH THEIR ALT. LATER WHEN THE FO AND I WERE DISCUSSING THE INCIDENT NEITHER OF US COULD REMEMBER THE CTLR ISSUING A DIRECTION OF TRAVEL OR SAYING ANYTHING LIKE XING TFC, ETC. SINCE I DIDN'T CONSIDER THE TFC A THREAT, I ASKED THE FO (WHO WAS THE HANDLING PLT) IF HE UNDERSTOOD THE CLRNC AND HAD THE TFC. HE REPLIED IN THE AFFIRMATIVE. I REACHED DOWN TO PICK UP SOME CHARTS THAT HAD FALLEN ON THE FLOOR DURING SOME TURB. WHILE I WAS HEADS DOWN, THE TCASII SOUNDED A TA. I LOOKED UP TO SEE THE TFC WAS XING R TO L AND WE WERE GOING TO PASS VERY CLOSE. ALL AT ABOUT THE SAME INSTANT WE GOT AN RA, I WAS PROMPTING THE COPLT TO TAKE ACTION AND THE CTLR WAS QUESTIONING WHAT WE WERE DOING. WE PASSED ABOUT 2 MI IN FRONT AND 500 FT BELOW THE COMMUTER PLANE. THE COMMUTER FLT FELT THE DISTANCE WAS MORE LIKE 1 MI. I WAS TOO BUSY TRYING TO KEEP A VISUAL CONTACT TO NOTICE THE DISTANCE ON THE NAV DISPLAY. AFTER WE WERE CLR OF CONFLICT, I ASKED THE FO WHY HE DIDN'T WATCH THE TFC A LITTLE CLOSER. HE SAID HE THOUGHT THE TFC WE HAD INITIALLY SEEN AT 11 O'CLOCK WAS THE TFC IN QUESTION AND WE WERE PASSING BEHIND THEM.

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.