Twenty seconds may seem insignificant, but in the context of a railway accident they can prove decisive—and cost dozens of lives. That reality was tragically underlined on Sunday by the derailment of an Iryo high-speed train in Adamuz, Cordoba. The train entered the adjacent track, along which an Alvia service was travelling from Madrid’s Puerta de Atocha station to Huelva.
Renfe’s president, Álvaro Fernández Heredia, said on Monday that the time gap between the two trains travelling in opposite directions was “apparently just 20 seconds”. He explained that the rail network is equipped with a safety system designed to block the line and trigger an emergency stop when an obstacle is detected. However, the extremely short time interval meant the system did not activate.
Fernández Heredia said the causes of the derailment remain unknown but ruled out human error in an interview with Spain’s Radio Nacional. He pointed to the presence of a recently installed high-speed safety system known as Linear Train Influence (LZB), which is designed to correct erroneous driver decisions.
The LZB is a continuous control system that transmits speed and braking instructions directly to the driver’s cab. It operates via cables embedded in the track that communicate with antennas on the train, allowing for near-autonomous control. It works in conjunction with the PZB system, another train protection and in-cab signalling mechanism intended to regulate speed and prevent human error. Despite these safeguards, responsibility ultimately remains with the driver.
Trains below speed limit
Renfe’s president also dismissed suggestions that excessive speed may have caused the derailment. Data from both trains, he said, show they were travelling below the permitted speed for the section. “They were already in the braking curve—one at 205km/h and the other at 210km/h. This is a 250km/h stretch, and the system itself prevents that speed from being exceeded,” he said.
He added that the derailment may have been caused by a fault either in Iryo’s rolling stock or in the infrastructure, but urged caution. “It is far too early to draw conclusions. This is an accident under unusual circumstances and there will be no immediate answers,” he said.
Fernández Heredia stressed that the immediate priority was supporting the victims and their families, including providing psychological assistance, as well as supporting railway staff. He described the incident as “one of the hardest moments of my life”.
‘Rare’ and ‘strange’
Iryo’s president, Carlos Bertomeu, described the accident as “rare” and “strange”. Speaking to journalists in Adamuz and visibly emotional, he expressed his condolences to the families of the victims and said the company was engulfed by “profound sadness”.
Bertomeu insisted that the train involved had fully complied with its inspection and maintenance schedule, with the most recent checks carried out only recently. “This is an unusual accident. It did not occur on a curve, but on a straight section. It did not happen at top speed, but at a moderate speed well within the train’s design limits,” he said. He added that the train, which is less than three years old, represents the latest technology and had met all maintenance and safety requirements.