Narrative:

What really caused this problem: 1) ATC/system demands that require turboprops to be below altitude so far from jfk. Air carrier aircraft have no business this low and fast in areas that are so heavily flown by GA aircraft. The pilot group has complained about this before! 2) specific to this situation was a VFR aircraft flying at an IFR altitude, not communicating with ATC, flight visibility 3-5 mi in typical summer haze. ATC was pointing out various and numerous targets. When the 'event' aircraft showed on TCASII at 5-6 mi, ATC was not talking to nor were they showing the aircraft on radar. When traffic was approximately 3 NM and 12 O'clock position, evasive action was taken -- a 90 degree change of heading was utilized versus climb/descent due to numerous targets above and below within 500-1000 ft of my aircraft. We did obtain a visual on the other aircraft. I could not tell if the other aircraft was also taking evasive action, but it was at 4000 ft (+/-100 ft). Thank the TCASII for this save! Someone is going to get killed on this pawling 2 arrival during marginal flight visibility! As a point of interest: 24 hours later, in the same location, I had almost an exact repeat of the grievous situation. However, this time it was during IFR conditions at 4000 ft. Again, ATC was not tracking or talking to the other aircraft. A vertical evasive maneuver was utilized this time. While the TCASII displayed the threat aircraft, no TA or RA was received. Perhaps it was a 'ghost' target -- I'll never know for sure.

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Original NASA ASRS Text

Title: AN SF2340 PIC PERFORMS EVASIVE ACTION TO AVOID A NON IFR CESSNA TYPE ACFT ON V99 AT HIS ALT OF 4000 FT 5 NM NW OF BDR, CT.

Narrative: WHAT REALLY CAUSED THIS PROB: 1) ATC/SYS DEMANDS THAT REQUIRE TURBOPROPS TO BE BELOW ALT SO FAR FROM JFK. ACR ACFT HAVE NO BUSINESS THIS LOW AND FAST IN AREAS THAT ARE SO HEAVILY FLOWN BY GA ACFT. THE PLT GROUP HAS COMPLAINED ABOUT THIS BEFORE! 2) SPECIFIC TO THIS SIT WAS A VFR ACFT FLYING AT AN IFR ALT, NOT COMMUNICATING WITH ATC, FLT VISIBILITY 3-5 MI IN TYPICAL SUMMER HAZE. ATC WAS POINTING OUT VARIOUS AND NUMEROUS TARGETS. WHEN THE 'EVENT' ACFT SHOWED ON TCASII AT 5-6 MI, ATC WAS NOT TALKING TO NOR WERE THEY SHOWING THE ACFT ON RADAR. WHEN TFC WAS APPROX 3 NM AND 12 O'CLOCK POS, EVASIVE ACTION WAS TAKEN -- A 90 DEG CHANGE OF HDG WAS UTILIZED VERSUS CLB/DSCNT DUE TO NUMEROUS TARGETS ABOVE AND BELOW WITHIN 500-1000 FT OF MY ACFT. WE DID OBTAIN A VISUAL ON THE OTHER ACFT. I COULD NOT TELL IF THE OTHER ACFT WAS ALSO TAKING EVASIVE ACTION, BUT IT WAS AT 4000 FT (+/-100 FT). THANK THE TCASII FOR THIS SAVE! SOMEONE IS GOING TO GET KILLED ON THIS PAWLING 2 ARR DURING MARGINAL FLT VISIBILITY! AS A POINT OF INTEREST: 24 HRS LATER, IN THE SAME LOCATION, I HAD ALMOST AN EXACT REPEAT OF THE GRIEVOUS SIT. HOWEVER, THIS TIME IT WAS DURING IFR CONDITIONS AT 4000 FT. AGAIN, ATC WAS NOT TRACKING OR TALKING TO THE OTHER ACFT. A VERT EVASIVE MANEUVER WAS UTILIZED THIS TIME. WHILE THE TCASII DISPLAYED THE THREAT ACFT, NO TA OR RA WAS RECEIVED. PERHAPS IT WAS A 'GHOST' TARGET -- I'LL NEVER KNOW FOR SURE.

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.