Dash 8-200
Air Traffic Control Fully Certified
Other / Unknown
ATC Issue All Types
Air Traffic Control Issued New Clearance
Airspace Structure
While working 3 positions combined (HAARP; NOBBI; & NYACK) Air Carrier X was on RADAR vectors for a visual approach to Runway 34 at HPN; 7 miles West of HPN; on a southeast bound heading level at 2;000 FT; which is the MVA in that area. I pointed out a VFR aircraft on a converging course that was level at 1;500 FT indicated while they were 7 or 8 miles apart. After making a few transmissions to other aircraft on my frequency; I noticed the VFR was now 1 mile away from Air Carrier X and indicating 1;800 FT. I issued the traffic alert and turned Air Carrier X further right to avoid the traffic. Air Carrier X responded to an RA and climbed to about 2;300 FT. When Air Carrier X responded to the RA and climbed; he entered the departure path off of HPN. Luckily there were no departures at this time. This event occurred because of the dangerous airspace design surrounding HPN. There are too many IFR operations in and out of HPN to have such a limited Class D surrounding the airport. The only way to prevent a re-occurrence of this event is to expand the controlled airspace around HPN. To allow VFR's to fly at any altitude around HPN and force IFR flights to respond to RA's 7 miles from the landing airport is dangerous. The airspace is too complex as is with EWR; LGA; JFK; and TEB all within 20 miles of it. I suggest [lowering] the NY Class B floor to a minimum of 1;500 FT or expanding the Class D around HPN to a Class C with a minimum of 10 DME around the airport from 1;500 FT to 3;000 FT.
N90 Controller described a TCAS RA event while vectoring an IFR aircraft to HPN; the reporter noting that current airspace design is problematic and should be changed to prevent future occurrences.