Narrative:

Response to an RA in the vicinity of sussex (fwn) and west milford (4n1) airports around the sax VOR. We were at 4000 ft on vectors for the runway 19 approach into teb. ATC cleared us to descend to 3000 ft. In the descent we got a TA for traffic at our 10 o'clock 200 ft. Below us. We arrested the descent at about 3600 ft. ATC also issued us a traffic alert for the same target. We queried ATC about the traffic. We then got a descend RA command to which we responded. We observed a low wing single engine aircraft fly over our captain side direct view window at approximately 100 ft [lateral distance]. We alerted ATC to the RA response he said he was not talking to the traffic. We then proceeded to teb without further incident.

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Original NASA ASRS Text

Title: EMB-135 First Officer reported an NMAC in the vicinity of FWN and 4N1 airports on arrival to TEB.

Narrative: Response to an RA in the vicinity of Sussex (FWN) and West Milford (4N1) airports around the SAX VOR. We were at 4000 ft on vectors for the Runway 19 approach into TEB. ATC cleared us to descend to 3000 ft. In the descent we got a TA for traffic at our 10 o'clock 200 ft. below us. We arrested the descent at about 3600 ft. ATC also issued us a traffic alert for the same target. We queried ATC about the traffic. We then got a descend RA command to which we responded. We observed a low wing single engine aircraft fly over our Captain side Direct View window at approximately 100 ft [lateral distance]. We alerted ATC to the RA response he said he was not talking to the traffic. We then proceeded to TEB without further incident.

Data retrieved from NASA's ASRS site 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.