Transportation officials have said that a safety system known as Positive Train Control could have prevented the deadly Amtrak train crash in South Carolina over the weekend. Now the AP reports that crews were actually installing it when the accident occurred. In fact, the very installation process may have played a role in the accident. Automated signals that could have warned the Amtrak train to stop before reaching the switch sending it down a side track were turned off as workers installed the GPS-based PTC system, said National Transportation Safety Board Chairman Robert Sumwalt. The Amtrak train soon crashed into a parked CSX freight train. “They were performing upgrades to the signal system to get it ready for Positive Train Control,” said Sumwalt, per the New York Post.
The Amtrak engineer sounded his horn seven seconds before the crash and applied emergency brakes three seconds before the train collided with the other locomotive at 50 mph, Sumwalt said, citing information from the passenger train's data recorder. "The expectation for the Amtrak crew is that they were clear," Sumwalt said. Positive Train Control is already installed in parts of the US. The system is designed to prevent two trains from traveling on the same track at the same time. That's what happened early Sunday in Cayce, South Carolina, when the New York-to-Miami Amtrak train hit the CSX train. Two Amtrak employees, a conductor and an engineer, were killed and more than 100 passengers were treated at hospitals for injuries.