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Train Derailment 3

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dik

Structural
Apr 13, 2001
25,618
CA
In Washington state, derailment killed 3 people and some still seriously injured. Part of the problem it seems is the design of the rail. From the BBC.

"A US passenger train that derailed, killing three people, was travelling at 80mph (130km/h) on a curve with a speed limit of 30mph, data from the train's rear engine indicates."

The rail was supposed to be a high speed rail and it seems really silly to have a 30mph curve on it.

link:
Dik
 
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Latest word is that it was travelling at 128 km/h in a zone where the max is 48 km/h.
 
Yup... but it seems silly that you would design a high speed rail with corners that were only suitable for 30mph. I wouldn't have expected that, and it was the 'maiden' run. The rail line was billed as a 'high speed line'.

Dik
 
30 mph was high speed in 1829.

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Dik,

A few years, I sat through a presentation at a conference about a "high speed rail" line in the planning phase between Des Moines, IA and Chicago (with future expansion to Omaha, NE). It was to go at 80 mph where it could, but wherever it went through a community (town, village, city), it still had to slow down to 30mph (or slower) since the plan was to use the existing freight track. So, calling it "high speed" is more of a marketing/branding angle, and not completely representative of operation. Without knowing ANYTHING about this event, I would guess the high speed train is utilizing existing track, and the operator (engineer?) of the train missed that they had to slow down.

At any rate, "high speed rail line" doesn't necessarily mean 80mph all the time, at least, not if it's using existing track.
 
It's not a high-speed rail. It's a shorter path than the other route. It's only the train that is designed for moderate speeds. "The train was running on track previously used for occasional freight and military transport," so it's not a purpose built route for unrestricted high-speed rail.
(ETA - I was responding to dik)
 
For some reason yet unknown, the automated speed control safety ststem was not activated.

Also, the run may have been inaugural, but previous runs and testing had been made.
with no issues as far as has been reported.

The route has long been a controversial topic, being in the courts, too, over the years.

Mike McCann, PE, SE (WA)


 
winelandv:

80 mph is not high speed for rails... Europe has several lines that are several times faster than that. If marketing is the reason for calling it 'high speed' then marketing is partly to blame. This was the initial run, and, the engineer may not have been sufficiently trained.

Dik
 
It was the initial run with passengers. It was not the first time an engineer ran the train down this route.

As for the design that included the need to drop to 30 MPH, the alignment had to cross from running parallel to one side of the highway to running on the other side. Unless it crosses at a shallow skew elevated above the highway for extended length of track, it has to zig and zag to get across.

I like to blame marketing for a lot of things. But this is a stretch.

 
Take a look at Google Earth for Dupont, WA and this area and you will see the railroad, an old alignment, is winding through some hilly area with several curves. No way for an 80 mph speed un0less the rails are banked to allow for it. That's very unlikely since the rail line also is used for freight. Reminds me of the passenger trains in Sweden and their twisty alignments. Instead of banking the curves, can you imagine they bank the position of the passenger cars on their trucks. Riding in the cars you get tilted back and forth as if the rails are banked. Aside from wearing the wheel flanges and rail edges it seems to work, but unlikely would work for an 80 mph speed on a 35 mph curve.
 
@dik, many railways (also in Europe) are very old. Some sections gets upgraded and then some dont. Its a matter of money.
 
@JohnRBaker, but why did they delay the implementation of a safety system? Because the industry asked for it to be delayed and threatened to stop service!
 
Perhaps, but then the auto industry objected to seat belts, air bags and emission controls, but they're all standard equipment now on every vehicle sold in America.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
Train was going 81.1MPH at a 30MPH turn.

Two 30MPH speed limit signs, one 2 miles out, one close to the turn.

Train has been running that track for 6 weeks.

I believe an engineer is required to pass that track 8 times before passengers are allowed to travel with that engineer on that stretch of track.

Those engines have inward facing cameras that can be called up for realtime high res color video viewable at dispatch.

All new engines have cellphone detectors that alert dispatch of ANY cellphones that are ON in the cab and result in immediate response from dispatch.

The cars involved in the WA wreck are made in Spain and are very lightly built with two cars sharing three sets of axles. (That's why the wreck seemed to have lots of paired cars). They are built like motor coaches (buses) unlike normal heavy duty rail cars. They are not allowed in most states due to their not meeting federal guidelines. They are allowed in WA and 5 other states under special federal wavers.

They spent $180.7M to put that shortcut into service to save, (I believe), 15 minutes. Worth it?

The lead locomotive ended up more than 120 feet from the tracks.

All engineers are handed between one and about 8 sheets of paper showing all speed restrictions on the pending trip. There are often more than a dozen special speed restrictions on typical trips. Speed restrictions can be caused by things happening near tracks and weather.

The engines are extremely new and made by Siemens. They have had so many problems it's taken a year to actually start putting them into service. In some units the throttles work in reverse to the historic normal. (Can you imagine an airliner where the throttles work in reverse?) I have not been able to find out if these particular engine are the wacky reverse throttle types.

I believe there are seven complete trains for that particular run. Two are owned by the state of WA, two by Amtrak, and the last three I don't recall. The one that just went on the ground was owned by WA.

PTC Positive train control implementation has so far directly cost the rail companies approximately one billion dollars. It's been very hard to implement. (Note the changing pages of speed limits noted above.)



Keith Cress
kcress -
 
"The engines are extremely new and made by Siemens"

The P42 that was pushing was most definitely not built by Siemens, it's a GE product. I'm assuming you're referring to the cab car.
 
Interesting.
Looks like the series 6 tilting carriages used on this line, but the series 8 for the rest of the US system.

it will be interesting to see how many times the driver ACTUALLY ran the line in that direction. One warning sign 2 miles out doesn't sound enough to me, but I'm not a train driver or designer. Maybe a little more graduation in speed limits required.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
I was most impressed with the way the embankment seemed to have kept the engine upright after it left the track. The side of the engine looked severely smashed and there's a new notch in the embankment at the curve that seems to match.

I can see the hesitation about PTC. One looks at the fleet cost of implementation along with the track indicators for short-range communications and then factor in that it's a system that overrides the engineer and compare the current rates of failure of engineers while also considering that there will be new failure modes. I'm not certain that PTC is an overall best solution to the problem of engineer's operating problems.

One solution that I would have pushed for is a GPS/Cellular comms based location system that alerted the engineer, much like terrain and collision avoidance systems in aircraft typically do. This could have been deployed cheaply and without the headache of adding additional failure modes to train control. However, doing this as an interim solution would certainly have ended the push to full autonomous taking of control. The big advantage to an alerting system is that multiple systems could be deployed on a single train, allowing the conductors to intervene if required. The disadvantage is that there is no good autonomous way to detect which of any parallel tracks a train is on, so mis-tracked trains could still be a problem.
 
I can very nearly imagine the recommendations from the report now - some rehash of:

"Having regard, therefore, to all the circumstances of this serious accident and to the criticism, to which my attention was particularly drawn, that both drivers concerned, though running approximately on time, may have been exceeding a speed reasonably justified by visibility conditions, I recommend that the Company should take early steps to reach decisions, with a view to applying Warning Control to high speed services on their Trunk Routes."

(Extract from Report by Lt.-Colonel A. H. L. Mount, C.B., C.B.E. on the Collision between two Passenger Trains which occurred on 10th December, 1937, at CASTLECARY on the London and North Eastern Railway, HMSO, 1938).

So why does this issue keep coming up without ever really getting implemented very enthusiastically or thoroughly? On the one hand, the systems are expensive and the proportion of rail accidents they might have any influence on is genuinely low. On the other hand, the accidents they do prevent tend to be the catastrophic ones that grab world headlines.

A.
 
"They spent $180.7M to put that shortcut into service to save, (I believe), 15 minutes. Worth it?"

The re-route also put the train across a lot more level crossings, increasing pedestrian/auto risks. And, for passengers, takes you down the "scenic[ponder]" I-5 corridor, rather than along the shoreline of Puget Sound. Pretty much a crappy decision all around. I think there was also a feeling that the high clay banks along the shoreline put the trains at risk due to mudslides (as happens fairly regularly a bit farther north between Seattle and Everett). Lots of politics leading up to the change.
 
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