atomic_fungus (atomic_fungus) wrote,

#4721: The answer is, as always, MORE GOVERNMENT!

NTSB says that positive train control is the only way to prevent accidents like this.

Uh, no, it's not. I'm pretty sure you can avoid wrecks like this if the guy driving the train is paying attention to what he's doing and going the speed limit.

Positive train control--PTC--is an automated system which governs the operation of the train. The idea is that the engineer can gun it for all it's worth, but once the train enters a speed limited zone PTC will slow the train down. All train moves are authorized by a central control location, which means the train doesn't move if a guy at a desk somewhere says it's not allowed to. It's estimated that fitting the nation's rail system with PTC would run about $22 billion, but owing to the way government always underestimates what something will cost, it's probably closer to $30 billion or more.

The real problem, though, is that you can't beat a human being for running a train. Machines don't have the judgement that an experienced engineer does, and it takes finesse to safely operate a train--especially a long one--safely.

In any event, the problem with the Amtrak wreck this week isn't that there was a problem with the infrastructure--as much as Democrats want it to be--but that the train was mis-operated. The engineer himself does not remember what happened, but the engine's black box says the train was going 106 MPH heading into that 50 MPH curve, and it further shows that the brakes were applied a few seconds beforehand.

Now, think about this: trains use air brakes. There's a reservoir in each car that provides the pressure to apply the brakes; the train line must be pumped up to pressure to release the brakes. When the maximum brakes are applied, it's referred to as "going into emergency" or "big-holing". When you big-hole the brakes, it takes time for the pressure in the train line to vent, which means that the brakes at the front of the train (where the brake valve is) apply before the brakes at the back of the train. There is not a huge propagation delay, but it is present, and when the train is moving at 106 MPH it can move a long way before all the brakes go on with the same amount of force. By the time the black box stopped recording, the speed of the engine's wheels had been reduced to 102 MPH.

Imagine what happens when you have a train moving too fast into a curve with some brakes applied at the front and none at the back. If you know physics at all, you can see the engine being pushed right off the tracks by the cars behind it.

PTC would probably have prevented this wreck, yes. So of course the Democrat answer is to force all railroads to implement an expensive system that at best is going to add nothing to the general safety and efficiency of the system, and at worst will be an expensive boondoggle.

Some people may remember seeing color bar codes on freight cars in the 1970s. It used to be that freight cars were labeled with the KarTrak system, which was meant to help railroads track how and where their cars were used. It did not work all that well, and was abandoned during the Carter administration. (Freight cars carried the tags for years afterwards, of course, because it wasn't worth the effort of removing the tags.) The system was required in 1968, but barely lasted a decade before being abandoned. These days, railroads use RF tags, which work very well, but it's a new system and does not descend from KarTrak.

Railroads are dragging their feet on the implementation of PTC because they don't want to spend the money for a system they do not need. Freight trains don't move that fast; they don't need to and typically they cannot. High speed is strictly the domain of passenger rail. Freight trains derail for a lot of reasons but speed is generally not one of them, and PTC is primarily a speed control system. It's a waste of money for a freight railroad to install PTC for trains that will never go faster than 40 MPH solely because Amtrak leases right-of-way from them.

Amtrak is nothing but a government boondoggle, something that can only exist because of government money. Absent federal spending, the railroad would not exist, because intercity passenger rail travel is economically unnecessary. If it were, there would be passenger railroads all over the place.

There are not. And for the most part intracity passenger rail only exists where government subsidizes it.

* * *

Speaking of government boondoggles, NASA is still futzing around with solid rocket boosters. They were looking at using F-1B engines in liquid-fueled boosters, but now they apparently are not.

F-1B is the modern retooling of the old F-1A used as the main engines for the Saturn V first stage, each one of them providing nine hundred tons of thrust. Just for comparison, the space shuttle main engines each provide 210 tons of thrust, for a total of 630 tons of thrust with three engines. One F-1A provides enough thrust to boost a space shuttle with 270 tons of thrust left to spare.

No one builds rocket engines like that any more, worse luck.

* * *

Just saw on the news a story about a firey oil train derailment, and the answer to that problem is to build f-ing oil pipelines. Keystone, anyone?

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