The Positive Train Control system has garnered plenty of attention after officials determined it was not installed on the Philadelphia railway where Amtrak Regional 188 hurled off the tracks Tuesday night, killing eight people and injuring over 200 others. Yet another system called Automatic Train Control which has been around for decades also wasn’t installed on the track, even though it’s installed on tracks throughout the country.
“Exactly what that system is designed to do is to prevent derailments due to overspeed,” said NTSB officials Robert Sumwalt.
Sumwalt says investigators don’t know where Amtrak’s ATC system has gaps though they intend to find out. Amtrak officials say high level management was unaware the fail safe system was missing near the curve where Amtrak 188 went off the tracks.
“We’re going to want to interview the people who were responsible for making those decisions,” Sumwalt said. “We ultimately will make an evaluation as to whether or not that was sufficient risk management.”
ATC is an older rail-based safety system that experts say works efficiently. It signals the engineer if the train exceeds speed limits. The engineer has a few seconds to slow the train before the safety system takes over and brings it to a stop. During Tuesday’s derailment, the train was traveling over 100 mph while entering a 50 mph curve, according to investigators.
“From my understanding there was supposed to be Automatic Train Control at that site,” said Dr. Allen Zarembski, the director of railroad engineering at the University of Delaware.
Dr. Zarembski, who consults the state of Pennsylvania on rail safety, was surprised when informed the ATC system was missing on the section of track where the derailment occurred.
“The coded signal, the coded pulse, automatic train control system is supposed to be in operation through the northeast corridor,” he said.
While the northbound section of track the train was traveling on does not have the ATC, the southbound side does have the safety system in place. Amtrak officials say the reason why it wasn’t installed on the northbound side is because they did not believe a train would be able to travel from Philadelphia’s 30th Street Station to the location of the derailment in Port Richmond at a fast enough speed to cause a dangerous situation.