Narrative:

New york approach control cleared us to turn to the initial approach fix for the VOR runway 24 approach in teb as well as a descent to 4;000 ft. The crew started the left turn and descent towards the fix; mid way through the turn the controller advised the crew of 'unverified VFR' traffic at twelve to one o'clock. Within a few seconds of the ATC warning; the aircraft TCAS sounded the initial traffic advisory. The crew began leveling the aircraft's descent however the VFR target keep climbing and turning towards us. Seconds after the initial advisory the TCAS sounded a RA climb command. The crew applied max thrust and began a RA climb to 5;400 ft. During this time the crew informed ATC of the RA and associated climb. The controller then issued a descent clearance to 3;000 ft. The crew again informed ATC of the RA climb and then complied with the ATC clearance to 3;000 ft. A visual approach was completed to runway 24 in teb without further incident. It is the opinion of the crew that the problem was caused by the VFR flight climbing into busy airspace used by countless aircraft in the new york area without first making contact with ATC. The problem was further compounded by the controller on duty issuing a late traffic advisory. It is clear that the controller had lost his situational awareness. This resulted in two aircraft on the same frequency responding to RA's in separate events within a few seconds of each other.

Related reports:

Google
 

Original NASA ASRS Text

Title: CL30 Captain experiences a TCAS RA while being vectored for a visual approach at TEB. ATC had reported the traffic just prior to the TA. An evasive climb is initiated until clear of conflict. A separate TCAS event was heard on the same frequency prior to switching; indicating to the reporter that the Controller was not paying attention.

Narrative: New York Approach Control cleared us to turn to the initial approach fix for the VOR Runway 24 approach in TEB as well as a descent to 4;000 FT. The crew started the left turn and descent towards the fix; mid way through the turn the Controller advised the crew of 'unverified VFR' traffic at twelve to one o'clock. Within a few seconds of the ATC warning; the aircraft TCAS sounded the initial traffic advisory. The crew began leveling the aircraft's descent however the VFR target keep climbing and turning towards us. Seconds after the initial advisory the TCAS sounded a RA climb command. The crew applied max thrust and began a RA climb to 5;400 FT. During this time the crew informed ATC of the RA and associated climb. The Controller then issued a descent clearance to 3;000 FT. The crew again informed ATC of the RA climb and then complied with the ATC clearance to 3;000 FT. A visual approach was completed to Runway 24 in TEB without further incident. It is the opinion of the crew that the problem was caused by the VFR flight climbing into busy airspace used by countless aircraft in the New York area without first making contact with ATC. The problem was further compounded by the controller on duty issuing a late traffic advisory. It is clear that the Controller had lost his situational awareness. This resulted in two aircraft on the same frequency responding to RA's in separate events within a few seconds of each other.

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.