A recent collision involving three Norfolk Southern trains in Pennsylvania has brought attention to the limitations of the automated braking system designed to prevent such incidents. The National Transportation Safety Board's preliminary report on the March 2 derailment revealed that the positive train control system did not activate to stop the trains due to specific circumstances.
The automated system was unable to prevent the second train from crashing into the back of a stationary train, nor could it halt the third train from colliding with the derailed cars obstructing its path less than a minute later. Railroad safety expert Chris Barkan noted that the positive train control system was not designed to address such scenarios.
Following a fatal 2008 collision in California, Congress mandated the implementation of the positive train control system to enhance rail safety. However, the system, which cost approximately $15 billion to develop, only functions under certain conditions.
In the Pennsylvania crash, the braking system did not engage as the eastbound train slowed down after passing a restricted speed signal but lacked a stop signal. Subsequently, the third train struck the derailed cars at a speed of 22 mph, as the system relies on signals and cannot detect obstacles on the tracks.
The collision resulted in the derailment of six railcars, including those carrying hazardous materials, but no spills occurred apart from diesel leakage into the river. Crew members sustained minor injuries, and the estimated damage totaled $2.5 million.
The NTSB indicated that the accident involved limitations of the positive train control system, with no mechanical issues identified. The ongoing investigation will scrutinize the railroad's protocols, procedures, and training practices.
Notably, Norfolk Southern's safety measures have faced scrutiny following a previous derailment in Ohio. Federal regulations mandate train crews to adhere to speed restrictions, especially in adverse weather conditions, to ensure safe operations.
Experts emphasize the importance of crew vigilance in observing speed limits to prevent collisions and underscore the need for continued safety enhancements in the rail industry.
