New technologies aimed at preventing passenger train accidents

SEATTLE -- The deadly train accident in New York state has all eyes focused on railway safety. Sound Transit is spending millions on new technologies to prevent an accident like that from ever happening here.

The technology is called positive train control (PTC). It’s a sophisticated system that allows train speed and other functions to be managed by on-board computers if train conductors make a mistake or get into trouble in some other way.

Sound Transit has never had a deadly derailment in the 13 years it’s been running trains. In the next couple of years, thanks to more than $50 million in new technology, its rail cars will be some of the safest in the world.

“The point is to prevent derailments, collisions and incursions in work zones,” said Kimberly Reason with Sound Transit. “It takes a very complex communications system to do that.”

Positive train control involves a series of sensors and transponders placed along the rails that constantly monitor the speed, location and routing of trains.

“It’s a very complex system of integrating communications to prevent the kinds of accidents that we saw recently so that all the train movement across the country, either freight or rail, operates safely,” said Reason.

Investigators say the Metro North train in last week's New York accident was going nearly three times the recommended speed before it derailed in a curve.

In a case like that, PTC computers would override the conductor and apply the brakes before it was too late.

“When a train is approaching at too high a speed or might be at risk of derailment, the computer on board the locomotive will power the train to slow or stop mode,” Reason said.

Cargo hauler BNSF is also investing in PTC, as are many other rail operators.

The system should be up and running -- and protecting Sound Transit's 10,000 daily riders -- in about two years.