Greek authorities are now focusing on the train engines in their latest investigations into the Tempi train disaster, a catastrophic head-on collision that occurred in central Greece in February 2023, killing 57 people.

A new report by a well-known Belgian railway accident expert, Yves Carton, suggests that the design and materials of the engines may have contributed to the deadly fire that engulfed the wreckage.

The report, commissioned in July 2023 by the parent company of Hellenic Train (Ferrovie dello Stato Italiane), was recently submitted to Greek investigators and experts at the National Technical University of Athens (NTUA). It examines whether the batteries, electrical systems, and fuel tanks of the train engines at Tempi played a role in intensifying the fire and explosions following the impact.

How the Engines May Have Made the Disaster Worse

Both the passenger train and the freight train involved in the Tempi crash were moving at high speeds—160 km/h and 100 km/h, respectively—far exceeding the 36 km/h impact resistance limit set by European safety regulations for train fuel tanks. The study raises concerns that these engines may not have been adequately designed to withstand such collisions.

Key findings include:

  • Batteries and electrical systems in the engines contained potassium and lithium hydroxide, which can produce flammable hydrogen gas when overheated. Battery packs were present in each train car, with one box per car containing 104.4 liters of electrolyte, behaving similarly to the engine batteries. Firefighters reported the presence of hazardous liquids in one of the train cars, likely originating from the spilled battery electrolyte, which mixed with firefighting water.
  • The traction converter’s coolant, though normally non-flammable, may have released toxic and explosive gases under extreme heat conditions. However, the air conditioning units were not found in the destroyed cars, leaving their contribution to the fire uncertain.
  • The pressurized air tanks on the trains, with a total capacity of 1,600 liters, could have acted like an aerosol and might have intensified the explosion and spread the fire faster. Notably, these tanks were not found in the wreckage of the passenger train, meaning their role in the fire remains uncertain.
  • Both trains were struck by 25,000 volts of electrical current because the nearest Public Power Corporation (DEI) substation failed to shut off power after the collision, as it should have in the event of a short circuit. The report suggests that the subsequent explosions within 10 seconds of the initial blast may have resulted from the simultaneous interaction of all these factors.
  • The report does not address the issue of potential solvent smuggling for fuel adulteration, as that was outside its scope.

New Questions for Manufacturers and Regulators

These revelations raise serious questions for train manufacturers Siemens and Krauss-Maffei, as well as European railway regulators.

According to reliable sources, these safety issues had been raised before the accident, given that approximately 5,000 trains of this type operate across Europe. However, the manufacturers had dismissed these concerns.