NTSB: NS engineer failed to follow speed restrictions in 2024 multitrain collision

The probable cause of a Norfolk Southern Railway intermodal train's collision with the rear of a stationary NS train in Pennsylvania last year was the failure of the intermodal train's engineer to operate within restricted speed limits and stop before hitting the other train, the National Transportation Safety Board concluded earlier this month in a final report.

Contributing to the accident were insufficient safeguards to compensate for human error, including current positive train control (PTC) systems that do not prevent train-to-train collisions during restricted speed operations, the NTSB report states.

The accident occurred March 2, 2024, on the Lehigh Line in the Allentown Road Subdivision near Easton, Pennsylvania. As a result of the first collision, the intermodal train derailed three rail cars that then fouled the adjacent main track. About a minute later, a second collision occurred when a third train struck the derailed equipment while traveling westbound.

As a result of the second collision, the third train derailed six cars and two locomotives. Three of the six derailed cars were placarded as hazardous materials tank cars: one containing ethanol residue and two containing butane residue. The tank cars did not breach or release hazardous materials.

The two derailed locomotives partially submerged in the Lehigh River and discharged locomotive diesel fuel into the water. Four crewmembers from the accident trains were transported to a local hospital, treated for minor injuries and released.

NTSB's investigation demonstrated vulnerability for single-point human failures that exist when trains are operating at restricted speed with or without PTC. On March 3, 2024, the day after the accident, NS issued a serious incident notice to its employees elevating awareness to the rules associated with restricted speed.

In addition, the Federal Railroad Administration (FRA) issued a safety advisory emphasizing the importance of complying with railroad operating rules when a train is operating at restricted speed, according to the report.

The accident underscores the importance of the FRA completing research into PTC technologies to prevent train-to-train collisions during restricted speed operations as recommended in the "NTSB Beyond Full Implementation: Next Steps in Positive Train Control" report, NTSB officials wrote.

Moreover, the FRA needs to continue work on analyzing data that will help revise training and increase oversight to ensure that operating crews use restricted speeds correctly. Until the technology is fully developed and implemented, however, the railroad industry will continue to rely on an inherently risky process of estimating restricted speed, the report states.

Click here to read the NTSB's final report into the accident.