Commuter train fires prompt NTSB safety alert

The National Transportation Safety Board (NTSB) this week issued a safety alert to warn commuter and transit rail operators to analyze the design of electric propulsion power and other critical systems. 

The alert stems from NTSB investigations into five incidents in which electric propulsion power systems have resulted in critical failures such as electrical arcing, fires and smoke and damage to electrified systems. The incidents placed passengers and crew members in danger, NTSB officials said in the alert.

"As the nation’s rail infrastructure ages, transit and commuter operators are experiencing critical failures related to electric propulsion power systems, putting the traveling public at risk," NTSB officials said.

The recent investigations include a Feb. 6, 2025, incident in which electrical components of the lead rail car of a Southeastern Pennsylvania Transportation Authority (SEPTA) Regional Rail train caught fire as it departed Crum Lynne Station in Ridley Park, Pennsylvania. About 325 passengers and four crew members on board at the time. Over the course of the year, the NTSB investigation expanded to include four additional electrical fire or smoke events.

According to the NTSB safety alert:
• Flooding or drainage issues can expose electrical cables to water intrusion and cause cable insulation to degrade;
• Worn contact surfaces on electrified third rails, collector shoes or pantograph heads may cause intermittent contact, which can lead to arcing; and
• Loose or corroded electrical connectors and joints on catenary wire or third-rail systems can increase electrical resistance, which can generate excessive heat in electrical components and lead to fires, electrical shorts or other dangers.

Recent NTSB investigations have found some electric propulsion power systems — such as third-rail systems or overhead wire catenary systems — have merged newer technologies with legacy components, introducing new failure modes. Temporary repairs and undocumented changes to third-rail or catenary systems, as well as aging electrical component tolerances that drift over time from their original design performance criteria, can also cause critical electrical problems, the alert states.

Such critical failures may not be adequately detected or mitigated by transit and commuter rail operators’ existing maintenance and inspection plans, according to the NTSB.