Extend the Second Avenue Subway to the Rockaways?

In 1999, the Regional Plan Association proposed a new subway service route. It would have operated from Manhattan to Brooklyn via the Montogue Street Tunnel (currently used by the R line) and to Jamaica via the LIRR Atlantic Branch (Flatbush Avenue Brooklyn to Jamaica which would have to be converted to subway use ending commuter rail) and on to Kennedy Airport via the Air Train. This idea was never endorsed by either elected officials or the MTA. 

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