The True Dangers of Long Trains | Hacker News Reader

The True Dangers of Long Trains

propublica.org

44 pointsPaulHoule9 comments

"Today, the rail administration says it lacks enough evidence that long trains pose a particular risk."

This is ridiculous, in fact outrageous. We've been using trains and railroad technology for about two hundred years and the engineering is well understood. If procedures now require trains to exceed the once-understood safe limit of 1.4 miles then administrators should automatically set up a testing program to determine new parameters and operational safety limits.

What's the purpose of having regulators who cannot act proactively before an accident? If operational parameters change from the accepted norm or standard then then a reappraisal of the regulations should happen automatically.

It really is unbelievable considering what the train was hauling. It wasn't just a long coal train:

> It had five locomotives at the front and 136 cars trailing behind, about half hauling hazardous material: propane, isobutane, ethyl alcohol, phosphoric acid and molten sulfur heated to 235 degrees Fahrenheit.

I could have killed a lot of people. It seems really dangerous to play fast and loose with those rules while also carrying super dangerous cargo. It's very easy to imagine the wrong composition of those dangerous trailers getting derailed.

How is rail safety handled in the US? Is every company responsible for itself with little oversight or are there more detailed rules? I wonder how this:

> It happened in September 2005 when a 1.5-mile-long BNSF train tried to fit into a siding in Missouri that was 1.4 miles long.

could have happened. It does not make sense to me. Shouldn't there be a computer saying no to the scheduling or at least some rail safety system?

> Shouldn't there be a computer saying no to the scheduling or at least some rail safety system?

It's called Positive Train Control (PTC).

https://railroads.dot.gov/research-development/program-areas...

https://en.wikipedia.org/wiki/Positive_train_control#Deploym...

The wiki includes a lot of good details about the challenges, for example no unified implementation and many "optional" (but basic) features that don't have to be used (but should; i.e. real time tracking of cars and locomotives in an identical fashion). By itself it won't stop collisions -- but it's the tech that, if used correctly, should.

Rolling it out is also non-trivial, and making PTC 2.0 happen in the future has a lot of challenges. In many ways it's easier to automate aircraft than it is railroads: you have the entire sky, lots of room to move, great visibility once above a certain altitude, and different altitudes for stacking traffic (e.g. one plant at 10000 ft, another at 17000 ft, another at 20000 ft). The challenge is mostly emergencies, and how to land/take off. Trains, meanwhile, have to share space with a lot of things that planes never do, such as avalanches, broken down cars, and routes that run though residential areas.

Plus railroads have plenty of money and are publicly traded -- they lobby as good as anyone. Many of the recent issues aren't due to any fancy control systems (or lack thereof), but the Trump administration allowing hazardous materials to be re-labelled as non-hazardous, and thus allowing them to travel at higher speeds.

malloc doesn't always return null when it should

The article mentions that a car in the main derailment incident contained molten sulfur, which apparently exists a temperature slightly above boiling water. I reviewed the Wikipedia page searching in vain to find some reason why it is shipped in its molten state (not to mention how the temperature is maintained while the train is in motion). Any clues?

Tis an interesting Google hole

> Large quantities of molten sulphur are transported by rail. An insulated sulphur railcar loaded with 40 to 70 tonnes of sulphur at 135oC (275oF) will stay molten for 10 to 14 days even in cold climatic conditions. This is possible because of the solidification of a small amount of sulphur on the inner wall of the tank that effectively insulates the remainder of the tank contents. When the tank car arrives at the customer, the car is heated using steam to melt the small amount of solid sulphur on the inner walls before the tank car is unloaded.

http://www.sulphuric-acid.com/techmanual/storage/trans_sulph...

Even molten iron is sometimes shipped around, though obviously that won't keep liquid for quite as long. Most commonly this only happens as internal works traffic, but sometimes rationalisation and works closures might leave producers and consumers somewhat separated, in which case that kind of traffic might traverse the public railway network, too.

E.g. since the closure of the Völklingen Ironworks (now a World Heritage Site), the neighbouring steelworks have been supplied form the remaining ironworks at Dillingen, approximatively 20 kilometres away. The liquid iron is carried via the regular railway line connecting the two towns.

A liquid, even if hot, is much easier to handle (pipes) than a powder.

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