First Cordoba accident report confirms marks on derailed train's wheels were caused by already existing track fracture
The indentations on the wheels and the deformation of the track align with the hypothesis that the track was already broken
The first report of the committee investigating the serious train crash near Adamuz states that the track on which the derailed Iryo train was running had been previously "fractured" - a fault that is thought to have ultimately led to the incident and the collision with the Alvia train.
The "notches on the wheels and the deformation observed on the track are compatible with the rail having been fractured," the CIAF commission's preliminary report says. This first official document also states that the "available information" shows that the rail fracture "occurred prior to the passing of the Iryo train involved in the accident and, therefore, prior to the derailment".
The notches were caused because the fracture creates a "step" in the track "that would strike the wheel rim". The fact that the notches are present only on the wheels of the train's odd-numbered axles, the document states, "is consistent with the first wheel of each bogie receiving the impact from the head of the fractured rail.
"The first impact also deformed and lowered the struck rail, both because of the contact and because it had to bear the weight of the first wheel," the CIAF report says.
"At speeds of around 200 km/h, the second wheel passes so quickly (roughly three hundredths of a second later) that the impacted rail does not have time to recover from that deformation and therefore does not strike the second wheel of the bogie in the same way as it did the first," the report states.
While the commission has confirmed this in the preliminary report, it has stated that "this hypothesis (...) will have to be corroborated by further detailed calculations and analyses".
The next step, as SUR reported on Wednesday, is to send the rail samples to a metallographic laboratory to determine the possible causes of the fracture. In the coming weeks, the recordings from the black boxes of the trains will be downloaded. Once "the cause of the fracture has been determined, new lines of investigation can be established".
