I want to track GA helicopter traffic coming and going from NYC. I know that most routes the helicopters fly require them to pick up a transponder code from ATC, which means they are in the system.
Is there a public feed of that ATC data?
Just to clarify, As far as I understand, sites like flightradar24.com and flightaware.com only track aircraft transmitting ADS-B out or with Mode-S transponders. I'm interested in tracking aircraft with Mode-C transponders that have picked up a unique transponder code in order to enter the class B.