Narrative:

Air carrier X flying at 5000 ft, northeast of the yardley VORTAC on a vector for newark airport. Our heading was northerly (010 degree I believe). The WX was VFR with 15 mi visibility. The first indication of any potential conflict was a TCASII TA at 10 O'clock and I believe 500 ft above us. I acquired the light aircraft around 3 mi and plus 400 ft on the TCASII on a converging heading. Ny approach called out mooney traffic to us. The target did not maneuver other than to continue a slow descent towards us. At 1 NM and plus 200 ft I began to climb to go over the descending aircraft. Just as I did this we got an RA to descend, but I continued the climb I had already initiated. TCASII later commanded a climb once the geometry had changed. Ny approach directed a right turn to 050 degrees, but I could not go belly up to a close-in threat and so I climbed until the aircraft passed under and behind us. We climbed to approximately 5500 ft. The mooney continued unaffected in a slow descent passing about 100 ft below us as we climbed and several hundred ft behind us. Once clear we began our turn and returned to 5000 ft. I believe without the TCASII and our sighting of the target, ny approachs turn would have been too late to prevent a midair. My captain initially saw another aircraft and was late to acquire the threat, and thus I am not sure whether we called the traffic in sight. My air force habits had dictated 'nose high goes high' which was shy I climbed to open the spacing quickest. Another case of see and avoid -- I'm not sure the other guy ever saw us.

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Original NASA ASRS Text

Title: ACR X TCASII TA RA HAD NMAC WITH VFR SMA. SEE AND AVOID CONCEPT.

Narrative: ACR X FLYING AT 5000 FT, NE OF THE YARDLEY VORTAC ON A VECTOR FOR NEWARK ARPT. OUR HDG WAS NORTHERLY (010 DEG I BELIEVE). THE WX WAS VFR WITH 15 MI VISIBILITY. THE FIRST INDICATION OF ANY POTENTIAL CONFLICT WAS A TCASII TA AT 10 O'CLOCK AND I BELIEVE 500 FT ABOVE US. I ACQUIRED THE LIGHT ACFT AROUND 3 MI AND PLUS 400 FT ON THE TCASII ON A CONVERGING HDG. NY APCH CALLED OUT MOONEY TFC TO US. THE TARGET DID NOT MANEUVER OTHER THAN TO CONTINUE A SLOW DSCNT TOWARDS US. AT 1 NM AND PLUS 200 FT I BEGAN TO CLB TO GO OVER THE DSNDING ACFT. JUST AS I DID THIS WE GOT AN RA TO DSND, BUT I CONTINUED THE CLB I HAD ALREADY INITIATED. TCASII LATER COMMANDED A CLB ONCE THE GEOMETRY HAD CHANGED. NY APCH DIRECTED A R TURN TO 050 DEGS, BUT I COULD NOT GO BELLY UP TO A CLOSE-IN THREAT AND SO I CLBED UNTIL THE ACFT PASSED UNDER AND BEHIND US. WE CLBED TO APPROX 5500 FT. THE MOONEY CONTINUED UNAFFECTED IN A SLOW DSCNT PASSING ABOUT 100 FT BELOW US AS WE CLBED AND SEVERAL HUNDRED FT BEHIND US. ONCE CLR WE BEGAN OUR TURN AND RETURNED TO 5000 FT. I BELIEVE WITHOUT THE TCASII AND OUR SIGHTING OF THE TARGET, NY APCHS TURN WOULD HAVE BEEN TOO LATE TO PREVENT A MIDAIR. MY CAPT INITIALLY SAW ANOTHER ACFT AND WAS LATE TO ACQUIRE THE THREAT, AND THUS I AM NOT SURE WHETHER WE CALLED THE TFC IN SIGHT. MY AIR FORCE HABITS HAD DICTATED 'NOSE HIGH GOES HIGH' WHICH WAS SHY I CLBED TO OPEN THE SPACING QUICKEST. ANOTHER CASE OF SEE AND AVOID -- I'M NOT SURE THE OTHER GUY EVER SAW US.

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.