The train's data recorder showed that it was travelling at about twice the posted speed limit of 80 kilometres per hour (50 mph) when it entered a bend in the line. The crash was recorded on a track-side camera which shows all thirteen vehicles derailing and four overturning. On 28 July 2013, the train's driver Francisco José Garzón Amo was charged with 79 counts of homicide by professional recklessness and an undetermined number of counts of causing injury by professional recklessness.

Eyewitnesses said the train was travelling at high speed before...
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derailing which was subsequently confirmed. Data from the train's black box revealed that 250 m (820 ft) before the start of the curve the train was travelling at 195 km/h (121 mph) and in spite of the emergency brakes being applied was still travelling at 179 km/h (111 mph) when it derailed 4 seconds later.[20] That confirmed a statement made in court by the driver, Garzón Amo, that the train was travelling at 180–190 km/h (111-118 mph) at the time of the accident. That was more than double the speed limit for that curve, which is 80 km/h (50 mph).

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There are 2 types of safety
one is before accident
other is after accident
now even after accident lhb coaches dont topple over each other or climb over each other. they remain in their position and only derail
talgo...
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coaches because of their light weight climb over each other and get damaged easily
i hope you get the point i want to make.