Amtrak Activates Crash Prevention System

It's called positive train control, and it can automatically stop a train that is traveling too fast, or is about to collide with another train. This weekend, Amtrak activated it between New York and Philadelphia. The previous week, the system went live between Washington and Philadelphia.

That now extends PTC from Washington D.C. to Boston — with one exception: the 57-mile Metro-North controlled territory between New Rochelle, NY and New Haven, CT. 

The MTA is in the process of installing the system. The region's three commuter railroads — Metro-North, Long Island Rail Road, and New Jersey Transit — all say they'll have PTC in place by 2018. That's a new deadline. Earlier this year, Congress extended the original one by three years.