Rail securityPositive train control could have prevented Amtrak derailment, but it’s not quite on track
Positive train control (PTC), a safety technology for rail transportation, may have been able to prevent the 12 May 2015 accident in which a northbound Amtrak Northeast Regional Train 188 carrying 238 passengers to New York from Washington, D.C. derailed near Philadelphia. PTC is a system designed to prevent train-to-train collisions, over-speed derailments, incursions into established work zone limits, and the movement of a train through a switch left in the wrong position. The Railroad Safety Improvement Act of 2008 (RSIA08) mandated that PTC must be implemented on about 60,000 miles of U.S. track by the end of 2015. The Federal Railroad Administration (FRA) estimates that the total capital cost for full PTC deployment according to law would be about $10 billion (about one year’s worth of capital investments for the major U.S. railroads) and annual maintenance costs of $850 million. The costs of implementing PTC remain a significant barrier – but not the only barrier. In addition to costs, PTC has faced barriers in technical implementation, namely system interoperability and allocation of communication spectrum.
On 12 May 2015, northbound Amtrak Northeast Regional Train 188 carrying 238 passengers to New York from Washington, D.C. derailednear Philadelphia while entering a curve at almost twice the designated speed limit. Eight people were killed and more than 200 injured in an instant.
Questions about how the train derailed, why the train was traveling more than twice the posted speed limit and how this could have been prevented surfaced immediately. Engineers typically have control over train speed, but the engineer of this particular Amtrak train currently reportshaving no recollection of the crash. Until the National Transportation Safety Board (NTSB) investigation is complete, we can only speculate on the root cause. However, we can discuss how this could have been prevented.
The promise of positive train control
Positive train control (PTC), a safety technology for rail transportation, may have been able to prevent this accident, and it is not the first time this sentiment has been echoed. In 2008, a similar accident prompted federal action.
On 12 September 2008, a passenger train collided with a freight train, resulting in twenty-five fatalities and 135 injuries in California. The engineer of the passenger train was distracted due to text messaging, and the NTSB specifically statedthat PTC could have prevented this accident.
Within a month, the Railroad Safety Improvement Act of 2008(RSIA08) became law and mandated that PTC must be implemented on about 60,000 miles of track “providing regularly scheduled intercity or commuter passenger transportation” by the end of 2015. The abnormally fast response can be attributed to support from Senator Barbara Boxer of California, who was the Chairman of the Senate Committee on Environment and Public Works at the time.
Unfortunately, the recent Amtrak accident came before the end of 2015 deadline, and this section of the Northeast Corridor did not have operable PTC. Further, it is highly improbablethat the 2015 deadline will even be fully met.
While implementation of PTC is moving forward in some places, system-wide implementation continues to face significant barriersdue to high costs, interoperability requirements and communication spectrum availability.
What is positive train control?
PTCfrom a functional perspective is a system designed to prevent train-to-train collisions, over-speed derailments, incursions into established work zone limits and the movement of a train through a switch left in the wrong position.
