Spain - railway services, ticketing and incidents (merged posts)

[whole diary]

[JayMac]

To me, it appears that the derailment begins with the generator car behind the lead vehicle. These trains have two generator cars, one at each end, with diesel engines to allow the sets to run on non-electrified sections of line.

[ChrisB]

Yep, that's the way I see it too.

[BerkshireBugsy]

I've just watched the sky 5pm news and allegedly the train driver who was in control at the time time of the accident (I believe there were two on board) had a Facebook where he allegedly previously  posted pictures of the train speedo showing higher than recommended speed.

[JayMac]

I've seen the posted picture of the speedo (showing just under 200 kph) but there is little context to it, or any reasoned conclusion of evidence, that at the time the picture was taken, the speed was inappropriate. Could have been on a stretch of line where 200 kph is permitted. Could have been during testing.

[TonyK]

BBC^» (British Broadcasting Corporation - home page) News reports that speed is being seen as the cause, if not the reason. The train was running late, and one theory is that the driver was trying to make up time. He has been put under investigation by the police. Both drivers survived, and there is a data recorder installed. The driver is said to have told his control centre by radio, after the event, that he had been travelling at what the BBC translate as 120 mph - more that 190 Kph.

Truly awful, and my thoughts are for the victims and families.

[Electric train]

It is truly shocking incident.

The cause if it is excess speed is that the cause, I am a little concerned with the consequence they way the carriages seemed to disintegrate and the train be came disarticulated.

[JayMac]

Much of the cause of the damage to the passenger vehicles and the disarticulation is, to my mind, probably as a result of hitting the concrete wall. I doubt that even the best of crashworthiness could withstand such impacts. Had the vehicles left the track where there was space for them to decelerate without hitting an immovable structure then they may have stood up to such a derailment better.

One looks at Grayrigg where a Class 390 Virgin Pendolino derailed at high speed. There the vehicles tumbled down an embankment and each coach stayed largely intact and in line. Had that train hit an overbridge or retaining wall then the outcome could have been a lot worse.

[BerkshireBugsy]

First of all apologies if this has already Ben posted.

In recent coverage on the TV they explained that prior to the stretch of track where the tragic accident occurred the train was (a) travelling at a high speed which was appropriate to the section of track  and (b) was controlled by a system called ETRMS .

However my understanding of the section of track where the accident occurred wasn't subject o ETRMS which means that the trains speed would not automatically reduced when exceeding the speed limit.

I also believe the black box recorders have been retrieved so hopefully they will allow the acts surrounding this accident to be determined

Like others my sympathies are with those who have suffered as a result of this event

[stuving]

French TV is reporting (as official information, not rumour) a couple of points that could be seen as point-scoring, but are justified as reassuring the French about their TGVs^▸ (Train a Grande Vitesse).

First, a TGV rake is very difficult to overturn or break up because the carriages are solidly pivoted to a shared bogie at each end. Two have derailed at high speed and while the power cars fall over the carriages never have. (Some years ago I recall hearing there had been at least six derailments with none overturning; perhaps the rest were at low speed.) The Talgo trains have little torsional stiffness at the coupling.

Secondly, the French balises not only warn of overspeed but brake the train for any speed limit, while these Spanish trains are only braked if exceeding a limit and above  200 km/hr. I can't make much sense of that, and it may not apply to all trains or lines, but it was stated as from Spanish railways.

You may also have heard these stories about one of the two drivers having a reputation for boasting how fast he can go. I think the scope for rumour feeding itself is a bit high in this case - I'd rather wait for the investigation.

[JayMac]

First, a TGV^▸ (Train a Grande Vitesse) rake is very difficult to overturn or break up because the carriages are solidly pivoted to a shared bogie at each end.

The train involved in this incident also has carriages with shared bogies. Difference though is the RENFE^▸ (Spanish National Railways (Red Nacional de Ferrocarriles Espanoles)) S730 has a single axle bogie.

A TGV rake taking a bend at more than twice the maximum permitted speed would, I suspect, also overturn. No design can overcome the laws of physics.

[TonyK]

A tank would be lucky to survive hitting that wall at that speed. BNM is right about the laws of physics - it looks like the power car almost made it around, but everything behind it tried to carry on in a straight line, like Newton said it would.

[JayMac]

And that second vehicle has a heavy diesel engine it, which probably means a higher centre of gravity. If so, then that explains why it is the first vehicle to tip.

It appears that the lead vehicle derailed after being pulled over by the generator car. This is apparent when you look at the video and see the rear of the lead vehicle being pulled outward before it topples. I wonder whether the train may just have made it round the curve if it was one of the similar all electric RENFE^▸ (Spanish National Railways (Red Nacional de Ferrocarriles Espanoles)) Class 130s that have no generators cars.

Evidence of the forces involved can be seen from some of the pictures that have been taken at the crash site. The diesel engine (weighing 6.6 tonnes) in the rear generator car was ripped clean out and ended up on the wall parapet.

[grahame]

And that second vehicle has a heavy diesel engine it, which probably means a higher centre of gravity. If so, then that explains why it is the first vehicle to tip.

It's been suggested that the Salisbury accident of 1906 in which a train went around the corner too fast would not have happened if the locomotive had been an older one with a lower centre of gravity been pulling the train (ref: O S Nock - Historic Railway Disasters and L T C (Tom) Rolt - Red for Danger).

[broadgage]

Accidents of this nature beg the question as to how many trains have previously taken the curve at excessive speeds and JUST got away with it.
If the train in the recent disaster took the curve at say 180KPH with tragic consequences, was this a one off error (momentry lapse of attention by driver who perhaps mistook his location) or had exceeding the speed limit become common practice, perhaps with other trains taking the curve at say 160KPH and JUST getting away with it.

In the UK^▸ (United Kingdom) speed limits are strictly enforced with drivers at risk of dismissal for all but the most trivial breaches.
This is however fairly recent, I can remember trains routinely exceeding speed limits, was there not a "140 club" years ago of those HST^▸ (High Speed Train) drivers who had reached 140 MPH.
SLIGHTLY exceeding the limit is most unlikely to result in an accident, there is a considerable safety margin. The real risk comes when speeding becomes the "new normal" and actual speeds very gradualy creep up to substantial excess speed.

If driver ABC has taken a curve at 100MPH without accident, then driver XYZ might be tempted to try 102MPH, and so on.

[stuving]

This is all new track. Surely any modern signalling system records the train speed, at least at every balise, and (with radio) in the fixed system as well as the train?