Narrative:

There were several VFR aircraft receiving flight following in the vicinity of hpn. Repeatedly; new york approach vectored us in very close proximity of aircraft at VFR altitudes (300-500 ft altitude differentials). Since we were in and out of IMC; it was very difficult to acquire the traffic visually. At one point; approach issued us instructions to fly a heading directly towards traffic; which was depicted as being only 300 ft above our altitude on our TCAS display. I immediately notified ATC that this heading would put us in direct conflict with that traffic. The approach controller appeared unimpressed and curtly replied that the VFR traffic was under their control and reissued the same instruction. Later; the same controller gave us a heading to join the localizer to ILS runway 16 at 3;000 ft and an approach clearance once established. There was traffic at approximately 3;300 ft depicted on our TCAS at approximately our 12 o'clock position; which resulted in an amber TA. While we attempted to visually acquire the traffic; the TCAS generated a red descend RA; which we immediately complied with. I notified ATC of our RA compliance. The controller appeared unconcerned. After the completion of the RA procedure; we were able to continue visually to the airport. Cause; 300 ft of vertical separation between aircraft is unacceptable; especially between piston and jet aircraft in marginal VFR conditions. The air traffic controller should have acknowledged our earlier concerns about our separation from slower VFR traffic and provided us with more conservative vectors; etc. There is terrain in the vicinity of hpn and the MSA in the quadrant where the TCAS RA occurred was 2;900 ft (south southwest of faran). The TCAS descend RA could have easily switched to an egpws terrain escape maneuver.

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Original NASA ASRS Text

Title: Air Carrier inbound to HPN talking with N90 voiced concern regarding the ATC handling with regard to separation from VFR traffic; especially considering the marginal weather conditions.

Narrative: There were several VFR aircraft receiving flight following in the vicinity of HPN. Repeatedly; New York Approach vectored us in very close proximity of aircraft at VFR altitudes (300-500 FT altitude differentials). Since we were in and out of IMC; it was very difficult to acquire the traffic visually. At one point; Approach issued us instructions to fly a heading directly towards traffic; which was depicted as being only 300 FT above our altitude on our TCAS display. I immediately notified ATC that this heading would put us in direct conflict with that traffic. The Approach Controller appeared unimpressed and curtly replied that the VFR traffic was under their control and reissued the same instruction. Later; the same Controller gave us a heading to join the localizer to ILS Runway 16 at 3;000 FT and an approach clearance once established. There was traffic at approximately 3;300 FT depicted on our TCAS at approximately our 12 o'clock position; which resulted in an amber TA. While we attempted to visually acquire the traffic; the TCAS generated a red DESCEND RA; which we immediately complied with. I notified ATC of our RA compliance. The Controller appeared unconcerned. After the completion of the RA procedure; we were able to continue visually to the airport. Cause; 300 FT of vertical separation between aircraft is unacceptable; especially between piston and jet aircraft in marginal VFR conditions. The Air Traffic Controller should have acknowledged our earlier concerns about our separation from slower VFR traffic and provided us with more conservative vectors; etc. There is terrain in the vicinity of HPN and the MSA in the quadrant where the TCAS RA occurred was 2;900 FT (south southwest of FARAN). The TCAS DESCEND RA could have easily switched to an EGPWS TERRAIN escape maneuver.

Data retrieved from NASA's ASRS site as of July 2013 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.