Saturday, 27 July 2013

Spanish Rail Crash – The Aftermath

[Update at end of post]

It’s not for Zelo Street to tell crash investigators, train operators, infrastructure companies and train manufacturers how they should go about their business, and that is not the point of this post. All that is set out here are the questions that one lay person would ask of those people, in the aftermath of the derailment near Santiago de Compostela last Wednesday evening.
An un-rebuilt 130 series train at Alacant Terminal

We now know that the European Train Control System (ETCS) was not being used on the Ourense to Santiago line by the type of train involved in the accident (the 730 series). But ETCS was being used by other trains that use the stretch regularly. Exactly how that works, and the desirability of different trains using different safety systems, I will leave to others.

The ETCS installation on the track towards Santiago ends around 4km from the derailment point, or just where drivers should start to brake for the curve. At least the signing-off of ETCS should give drivers a cue to slow their trains – if they are using it. The older ASFA system, to which ETCS hands over, does not give drivers a speed profile for their braking (although it apparently can be set up to do so).

Moreover, ASFA as installed at that location does not have any overspeed protection built in. That looks like a potentially serious shortcoming, especially when you re-examine the video of the derailment. Had the train been an un-rebuilt 130 series, it might even have got round that curve: what comes clear from a slow motion replay is that the front diesel generator car is the first to tip over.
That, in turn, appears to drag the coaches behind it off the track, as well as tip over the leading power head. Towards the rear of the train, the other diesel generator car can be seen tipping over and coming away from the rear power head as it hits the curve. Talgo coaches, with their low profile and therefore centre of gravity, should not be so easily prone to derailment.

That’s not to say that the 730 series trains are inherently less safe than their straight electric cousins: it merely underscores the need for overspeed protection at locations like that of the derailment. What is also disquieting is the loss of life: 78 out of 220 on board, or more than a third of them. Those are horrendous numbers. Why that happened could be down to a number of factors.

The sudden deceleration would not help. But there are accounts of seats flying around – they shouldn’t come away from their anchor points. Large pieces of luggage should be stowed in floor mounted stacks or between seats, and certainly not in overhead racks. And whether parts of the coaches are designed to deform, or crumple, in an accident can help protect their occupants.

So that’s a regular day at the office coming up for the crash investigators, then.

[UPDATE 28 July 1900 hours: El Pais, as a contact has pointed out to me, has noted that high speed rail is big business in Spain, and not just domestically. Contracts worth tens of billions of Euro are up for grabs, from Russia to Saudi Arabia to central Asia to South America to the USA. The industry employs 18,000 people in Spain - at a time when unemployment is grim.

So while investigators need to do a thorough job, and ensure the causes of the derailment are not only known, but also that a recurrence is demonstrated to have been prevented, the Government and all those employers with capital tied up in high speed rail will be hoping this does not hurt their businesses.

How the investigation remains transparent, with all the potential for special pleading from vested interests, will be an interesting circle to square. And the very best of luck to them]

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