Narrative:

Air carrier X was cleared direct to lrp at 16000 ft. Approximately 20 mi east of lpp, ZNY (135.75) advised us of VFR traffic, 12 O'clock at 12 mi at 17500 ft. Sun was in front of our aircraft about 25 degrees above the horizon. The TCASII next picked up and gave a TA at 12 O'clock, 6 mi and 700 ft above us (16700 ft). The TCASII next gave an RA to descend at 1500 FPM for the aircraft at 12 O'clock, and 300 ft and descending (16300 ft). A descent was initiated and a turn to the right begun. The TCASII gave another RA to increase descent from the aircraft at 12 O'clock and 200 ft above and descending. The traffic was picked up visually at about 1 mi, descending and passing left to right. I commenced a left turn and the traffic passed by us. I leveled off and then started a climb back to 16000 ft and had the first officer notify ATC. I believe the first officer had originally notified ATC of our originally beginning to descend. If the other aircraft had TCASII, then our RA to descend in light of its descending appears dubious. If the other aircraft did not have TCASII or it was not working, either of which is more probable, then ATC's early notification of the traffic at 12 O'clock, 12 mi, 17500 ft VFR was a valuable contribution to the subsequent event and outcome. A further notification by ATC that the traffic had begun a descent from the 12 mi advisory to our TCASII picking it up at 6 mi may have negated the necessity of our descending.

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Original NASA ASRS Text

Title: ACR X TCASII TA RA HAD NMAC WITH VFR LEAR JET IN VFR DSCNT. EVASIVE ACTION TURN DSND. SEE AND AVOID CONCEPT.

Narrative: ACR X WAS CLRED DIRECT TO LRP AT 16000 FT. APPROX 20 MI E OF LPP, ZNY (135.75) ADVISED US OF VFR TFC, 12 O'CLOCK AT 12 MI AT 17500 FT. SUN WAS IN FRONT OF OUR ACFT ABOUT 25 DEGS ABOVE THE HORIZON. THE TCASII NEXT PICKED UP AND GAVE A TA AT 12 O'CLOCK, 6 MI AND 700 FT ABOVE US (16700 FT). THE TCASII NEXT GAVE AN RA TO DSND AT 1500 FPM FOR THE ACFT AT 12 O'CLOCK, AND 300 FT AND DSNDING (16300 FT). A DSCNT WAS INITIATED AND A TURN TO THE R BEGUN. THE TCASII GAVE ANOTHER RA TO INCREASE DSCNT FROM THE ACFT AT 12 O'CLOCK AND 200 FT ABOVE AND DSNDING. THE TFC WAS PICKED UP VISUALLY AT ABOUT 1 MI, DSNDING AND PASSING L TO R. I COMMENCED A L TURN AND THE TFC PASSED BY US. I LEVELED OFF AND THEN STARTED A CLB BACK TO 16000 FT AND HAD THE FO NOTIFY ATC. I BELIEVE THE FO HAD ORIGINALLY NOTIFIED ATC OF OUR ORIGINALLY BEGINNING TO DSND. IF THE OTHER ACFT HAD TCASII, THEN OUR RA TO DSND IN LIGHT OF ITS DSNDING APPEARS DUBIOUS. IF THE OTHER ACFT DID NOT HAVE TCASII OR IT WAS NOT WORKING, EITHER OF WHICH IS MORE PROBABLE, THEN ATC'S EARLY NOTIFICATION OF THE TFC AT 12 O'CLOCK, 12 MI, 17500 FT VFR WAS A VALUABLE CONTRIBUTION TO THE SUBSEQUENT EVENT AND OUTCOME. A FURTHER NOTIFICATION BY ATC THAT THE TFC HAD BEGUN A DSCNT FROM THE 12 MI ADVISORY TO OUR TCASII PICKING IT UP AT 6 MI MAY HAVE NEGATED THE NECESSITY OF OUR DSNDING.

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.