A freight train's emergency brake is applied at 40 MPH. How long does it take to stop?

BNSF and Wabtec (which bought out increasingly-hollowed-out GE’s transportation divison) are working on a battery-electric locomotive that could be hooked up to a string of diesels and provide such regenerative braking. If they go further and run cables to the diesels, it could even recover dynamic braking energy from the other locos (which would otherwise be shunted off to resistor grids).

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A butcher is on a train heading from Chicago for Kansas City, traveling at 40 mph. Meanwhile a baker is on a train from St. Louis to Kansas city, traveling at 53 mph. Assuming that both trains left at the same time, what does the butcher weigh?

Lamb chops

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Police also shot at an emergency fuel cutoff switch

Ah yes, of course. Is there any problem guns can’t solve?

which had no effect

Oh I guess there is.

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Yep! You would confuse the heck out of most USians by saying, “roth.” Assuming you’re referencing the Queen’s English, that is.

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Heh, go to a service station in middle America:

“I had to transport some goods so I filled up my boot. Then some steam started coming out of the bonnet so I left it in a car-park and I need to rent a lorry. Do you think you can help?”.

“Sure, I’ll get someone to give you a lift.”.

“Why in the bloddy hell would I need a lift? Your station doesn’t even have two floors?”.

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If anyone ever wondered why London Underground trains have panels labeled “EPBIC”, it stands for “electro-pneumatic brake isolating cock”. Heh. (You will also often see DIC on the tube, which marks the location of the Door Isolating Cock).

You may also have noticed that on each car there is at least one dial which moves when the train stops; this is a pressure gauge for the pneumatic brakes.

IDK why no tube trains use regenerative braking.

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What happens when the brakes don’t do their job:

Donoteat got featured here recently I think. Cool podcast.

If it was a Cock Isolating Door, would that make it a…Cock blocker!!!

Ba-dum-dum, BASH.

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S Stock does have regenerative braking.

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I’m just the idea man. I was thinking in the abstract. :roll_eyes:

But you’re perfectly right, you’d have to put motors on every car, like a subway train. And that would be super expensive, unless the power output eventually paid for the outlay. But then there would be more maintenance, connecting them together, controlling them, etc.

Brit: (hands AA-branded Visa card to Yank clerk)
Clerk: “Alcoholics Anonymous has a Visa card?!”

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The engineer also attempted to apply the locomotive’s dynamic brake to slow the train to a crawl; dynamic brakes dissipate momentum (kinetic energy) by using the momentum of the train to drive the main generator, generating electricity, exactly like a regenerative braking system in a hybrid automobile, which slows the train. In effect this is very much like using engine braking in a car or exhaust/“jake” brakes in a tractor truck (even up to increasing the revs of the engine thereby making it harder for the engineer to discern whether the throttle was successfully placed into “full brake” or “full throttle”, as it turned out); however in this case the braking effect is totally unrelated to the engine itself. However, the engineer “inadvertently failed to complete the selection process”, meaning that the train’s engine was set to accelerate, not to brake. He then set the throttle for the traction motors at notch 8. If the dynamic brakes had been engaged as intended, this throttle setting would have used the motors against the momentum of the train, causing it to slow down. Instead the train began to accelerate. Therefore, the only functioning brake was the air brake on the locomotive, and this was not enough to counteract its engine power.[1]

from the CSX 8888 incident - Wikipedia, subject of Tom Scott’s video above

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In the north of England ‘wrath’ rhymes with ‘math’, except that ‘math’ is a silly Americanism for ‘maths’.

Anyway, for anyone who wants a more close up view of the North American rail system:

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That’s interesting, because the S stock still has the brake pressure gauges, and they still move when the train stops (or rather, they have when I’ve paid attention to them). I guess maybe they use regenerative braking to slow down, but engage the pneumatic brake when they’re at a dead stop?

The sequel :

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