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Karl1459

Derailment of Cascades #501, DuPont WA, 2017-12-18

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They have been doing testing for close to a year. Still haven't heard if PTC was in place and in service. Train was a Talgo Serie 6 USA transit, which has short cars like those seen, the cars did not break in half (as far as the photos I have seen anyway).

Nick

 

It is notable how the cars did separate.

 

See here for the far higher-speed derailmant at Compostela in Spain.

 

Admittedly this is not the same type of equipment, but I guess the overall dynamics are comparable.

 

Despite what happened, many of the cars did manage to stay attached.

 

Arguably, a train's ability to resist jackknifing in this type of situation can be life saving.

 

 

Overspeed in a corner with a Talgo train, my first though was of Compostela. There are definitely similarities between the derailments, and I think the probability of an overspeed derailment is absolutely growing. Was there PTC? If so why did it fail to prevent this derailment? Also the original poster who I didn't quote asked if the cars were short, or long and broken in half. That is a no, the train set itself obviously broke apart, the cars themselves seems to have remained largely intact.

Nick

Based on no current information whatsoever, I am reminded that a train crash can be a terrorist-type event, as when the Sunset Ltd was derailed west of Phoenix some 20 years ago.

 

The fact that this was the inaugural run of the new service, with attendant press and VIPs, contributes to my concern about that possibility.

 

None of the possible explanations for this tragedy are good in any way.

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www.amtrak.com

Amtrak Cascades services impacted

9:30 a.m. PT

 

Individuals with questions about their friends and family on this train should call (800) 523-9101.

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I am wondering where is the rest of the train?

 

There appears to be a number of cars on the other side of the bridge. The entire consist is some 13 cars plus the cab and the engine at the south end. Is the whole rest of the train derailed on the other side of the track which is not visible in the views being shown on TV because of difficulty accessing the area?

 

Yep, the entire train derailed right there and piled up. The Charger at the head of the train is on the ground on the other side of the bridge across I-5S. Visible from the Chopper. The Charger looks pretty badly beaten up too.

 

While a full investigation will establish the real cause, this looks suspiciously like an overspeed derailment on a curve.

 

This incidentally is the second Cascades derailment within a very short period of time.

Edited by jis

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I cannot imagine both the equipment and the crew not having been completely qualified and certified on the new route. But going into an S-Curve at 81.1 mph is pretty high. I guess no PTC in these guys, eh?

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For what it's worth, I found this about the Talgo in India:

 

"Okay, how does this technology work?

"Wheels of conventional coaches are joined by an axle underneath. Talgo’s wheels are mounted in pairs but not joined by an axle — instead, they are fitted individually on the coach. As a result, on a curve, the outer wheel (which has to cover a longer distance than the inner wheel) and the inner wheel are free to rotate at speeds of their own, largely foreclosing the possibility of derailment even at higher speeds. Also, the design of the coach is such that it senses the curve and shifts its weight in a manner that manages the tilt." http://indianexpress.com/article/explained/talgo-super-fast-bullet-train-indian-railways-mumbai-delhi-questions-performance-3029920/

 

Actually, a fixed axle is pretty good at preventing derailments. There is a famous video of Richard Feynmann explaining how it always seeks the center and is thus inherently stable.

 

The attraction of individual wheels is that you can provide low-level passageways between low-floor cars, leading to an overall low center of gravity which is an important component of the concept of passive tilting generally and Talgo trains in particular. Having separate wheels means there can be a minimal variation in the gauge which is an inherent disadvantage. This is to some extent compensated by some smart patented systems that Talgo invented applying pendular pressure to the wheels to force them to simulate the sinusoidal motion of fixed axles. But its a workaround. Further advantages are that the decoupling suppresses the propagation of vibrations caused by bad track geometry, and that the dynamics in which one coach guides the next smoothens the transition into and out of curves which reduces the tendency of wheels to climb the outer rail in tight curves and thus means the risk of derailamnt is reduced in those situations, which can be used to increase speeds.

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I am wondering where is the rest of the train?

 

There appears to be a number of cars on the other side of the bridge. The entire consist is some 13 cars plus the cab and the engine at the south end. Is the whole rest of the train derailed on the other side of the track which is not visible in the views being shown on TV because of difficulty ac

 

They are now showing aerial pictures... Most of the consist is on the other side.

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Is the angled car a really short car? Or is it broken in two?

 

 

Sent from my iPhone using Amtrak Forum

 

Talgo cars are shorter than your "regular" Amtrak car. I'm not certain which "angled car" you are referring to, but none of them look broken in half. Talgos share a wheel-set between two cars, so the car-end you can see (on the up-side-down car) looks a lot different than a normal car end.

 

peter

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The Amtrak train tracking site has it at 81 MPH just before the derailment. I do not know how much it would have slowed down by the incident site. There is no speed indicated at the brown dot (incident site?)

Our local news is also reporting that the train was doing 81.1 mph and that the max speed allowed was 79.9 mph. Though, as a non-train-type engineer, I would have hoped that the 79.9 mph limit had a bit of tolerance, and 81.1 mph would be within it.

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77 injured are being brought to hospitals.

 

Current reports are 6 fatalities.

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There appears to be a number of cars on the other side of the bridge. The entire consist is some 13 cars plus the cab and the engine at the south end. Is the whole rest of the train derailed on the other side of the track which is not visible in the views being shown on TV because of difficulty ac

 

77 injured are being brought to hospitals.

 

Current reports are 6 fatalities.

 

They are now showing aerial pictures... Most of the consist is on the other side.

 

 

http://komonews.com/news/local/derailed-train-falls-off-bridge-onto-i-5-lanes-south-of-tacoma

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Ugh, more fodder for the government to get rid of Amtrak instead of getting us the money to improve.

This is the third major Amtrak wreck in as many years. If they cannot operate safely, at some point it will stop being simply fodder and they will have to have some kind of reckoning. If (and I stress if) it does turn out to be an over speed incident, you have to wonder if the company learned anything from 188.

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CNN is showing the Charger completely off the tracks and upright on the 5 freeway. Both a Charger and a Genesis on the consist.

Edited by seat38a

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It should be noted that Talgo Trains are pretty light weight and can brake pretty quick... just because the train was doing 81 before the curve, doesn't necessarily mean the engineer didn't properly decelerate before reaching the curve.

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It should be noted that Talgo Trains are pretty light weight and can brake pretty quick... just because the train was doing 81 before the curve, doesn't necessarily mean the engineer didn't properly decelerate before reaching the curve.

On the other hand, this is a new line and although I can understand why there are 30mph sections on legacy lines, shouldn't an all new line be aligned to allow consistently high speeds, especially on greenfield sites.

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Is the angled car a really short car? Or is it broken in two?

 

 

Sent from my iPhone using Amtrak Forum

Talgo cars are shorter than your "regular" Amtrak car. I'm not certain which "angled car" you are referring to, but none of them look broken in half. Talgos share a wheel-set between two cars, so the car-end you can see (on the up-side-down car) looks a lot different than a normal car end.

 

peter

I understand Talgos. But there is one car, the main one they have been showing, that appears very short. The one dangling off the bridge.

 

 

Sent from my iPhone using Amtrak Forum

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It should be noted that Talgo Trains are pretty light weight and can brake pretty quick... just because the train was doing 81 before the curve, doesn't necessarily mean the engineer didn't properly decelerate before reaching the curve.

The upcoming investigation will be interesting to read in regards to the Talgo strength and crash worthiness.

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Is the angled car a really short car? Or is it broken in two?

 

 

Sent from my iPhone using Amtrak Forum

Talgo cars are shorter than your "regular" Amtrak car. I'm not certain which "angled car" you are referring to, but none of them look broken in half. Talgos share a wheel-set between two cars, so the car-end you can see (on the up-side-down car) looks a lot different than a normal car end.

 

peter

I understand Talgos. But there is one car, the main one they have been showing, that appears very short. The one dangling off the bridge.

 

 

Sent from my iPhone using Amtrak Forum

 

What about it? It is a standard length Talgo car.

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