Ok another goofy train question from yours truly?

Question

Ok I see trains with just one of those big engines pullin' what sometimes is over a 100 cars ... I know it is that many because I counted them ok? lol so my question is how can one engine even that size pull that many cars? I think some might have been loaded .. not sure .. but I don't think they all were so is that why?

wow a lot of great answers ... gonna be chore pickin' just one!

hey there lil' fella ... I'll take the first and last part of your answer as a compliment babe. ; )

heres some cotton balls hoghead! lol

wow that is a lot of ponies rango .. I sure didn't know that babe!

your right james it's gonna be tough pickin' just one for sure!

hi there ken ... hey thanks for the link .. that was interesting to watch ... I take it all that squealing was the wheels slippin'? ; )

Answer 1

This is not a goofy question, it shows you are observant. Most RR tracks are not on much of a grade, lots less steep than highways for instance. And steel wheels on steel rails have very little rolling resistance compared to rubber on pavement. Locomotives on freight trains have typically anywhere from 3000 horsepower clear up to 5000 so that is a LOT of ponies. Also, only the locomotive has to "punch" a hole through the air, the remaining cars have less wind resistance. Now you can see why trains are such a fuel efficient and less polluting way of moving freight. And fyi, I have been doing this since 1975, it's not slack that starts a train, most of us try to stop with the slack "stretched" so there is no movement. It's tractive effort and torque that moves trains.

Answer 2

There are several reasons these big locomotives can pull so many cars. Let's start with the basics:

1. Railroads use steel rails and the cars and other rolling stock use steel wheels. The coefficient of friction between these is extremely low. Once you get those railcars moving it doesn't take much to keep them moving. About the only means of moving goods that is more efficient is river barges. And you need rivers for those.

2. Railroads are designed to incorporate relatively low grades, meaning they don't climb hills very fast. If they have to go up a mountain the railroad will use switch-backs to move up to the higher levels. A three-percent grade, where you climb three feet in every one hundred, is considered pretty steep.

3. Those "big engines" are very powerful. They could supply electricity to a small town. They have a lot of wheels that are powered. Say you have one big locomotive with 12 powered wheels. That means a lot of traction and the ability to move a lot of stuff.

Chances are that some of the train cars were empty, but many were not. It takes a lot of power to get the train moving and a lot of power to get it stopped once it gets started.

Incidentally I have seen trains as long as 300 cars.

Answer 3

There are so many good answers.Who can choose just one? NO ONE CAN! That's because there are somany variables to starting a train. Warren D's answer is right. once a train is started it is normally easy to keep moving. The Cheese Cop is more accurate on loco weight. The weight of the locomotive helps it to maintain " wheel to rail contact". This is were Monotonous-life7 discription of horsepower and tractive effort of the electric motors comes in effect. If the wheels that pull the train can not maintain contact you get wheel slippage. And as jungone say's what good does it do if you can't stop.
The area I run trains , we normally use cw4400ac to the sd80's. (this is an AC corridor) The toonage for one 44ac is @22800 tons reduced by 10% for single loco operations. that would be around 20500tons for one engine. My grade is .5-1%. I have worked grades @2.5%. This dramatically reduces the toonage rating on all locomotives.
So to answer your question search all responces. Not one is totally right and not one is totally wrong. That includes mine.

Answer 4

Locomotive engines are able to pull cars by something that is called "slack action". Where the cars are hooked together those are called drawbars. These drawbars move in and out about 6 inches.
Now when a train is stopped, all the drawbars should be pushed in. Then when the engine goes forward, the drawbar on the first car pulls out, and the first car goes forward, then the same happens to the second car, then the third, and so on until the last car. It happens very fast, but the momentum of the locomotive and each car gets the train moving.
If there was no "slack action" a train would never move.

Answer 5

Modern trains are electric... thats right, electric. they have big diesels that run a generator to power the extremely powerful electric motors. electric motors put out MUCH more torque than any diesel engine could produce, ever heard of the Tesla Roadster? its electric and runs on lithium-ion batteries and can out accelerate even the best Lamborghini and Ferrari have to offer.

heres a nice little rule for towing: "anything can pull anything, trying to stop in a reasonable time is another story."

also, gear reductions are a necessity for towing extremely heavy loads, thats why semi's have 9, 10, and 12 speed transmissions. when a train gets ready to take off, it goes into the lowest gear, where the motor might be turning 5 thousand RPM but the train is barely rolling. example: try getting on a mountain bike and starting in the highest gear, its pretty hard; however, if you start in the lowest gear, you can take off pretty fast, even up a hill (what those gears are used for).

im no expert but id say a train could pull at least 100 fully loaded cars with no problem.

Answer 6

My father designs the brakes, trucks and couplings that are on most trains today and he is on the NTSB.
Diesel locomotives today are incredibly powerful but it is improved air brakes that came about in the 60's and 70's (my dad) that allowed long trains. Now when the man hits the brakes the brakes on the last car apply at virtually the same time as the ones at the front...very important for that to happen. Also the number of engines is based on the road ahead and the load. May be your train was loaded with plastic pellets or some less dense material.
Now with gas at this price train transport is again cost competitive. Too bad ford, gm et al conspired and colluded to destroy rail transport in this country starting back in the 20's. we are paying for that now in oh so many ways....keep driving those SUV's

Sure now they are making locomotives but if you read at all and want to read some history about how the auto manufacturers led by henry ford colluded to buy up as many rail companies as possible at about the same time that dealerships were being built. LA is perfect example of this effort. They had street cars everywhere. This started in the 20's and continued well into the 50's. So the "natural" death of rail was not so natural and now we pay for it everyday with the carnage on our highways some of the most dangerous in the developed world. I will seek the book that has this info. I read it 20 years ago for a class in Dearborn at UM that was focused on the auto industry. and post it here or on my profile

Answer 7

haha that's cute.
Look at all the answers you got in so little time. I think it's because your a girl. But hey, I can't blame em' lol

And about that question. Trains are strong. They are roughly 6,000 horse Power! With sometimes a 16 cylinder, engine.
Trains also need less power to start moving, since they are are nice smooth rail, other than rubber on even, not smooth roads.
They weigh alot, like 400,000. thats.. 200 tons!
I bet that train could pull those cars, loaded or not!
Hope I answered your question(s)
I think it's hott, your asking about trains. Last time I mentioned a train to a girl, I never saw her again. lol


Yes Louis dude, I was talking about GE SD90

Answer 8

I guess it depends allot on what is in the cars. Empty or loaded? And what kind of terrain it will be going over. Mostly flat?
I guess you have seen the back to back engines and engines in front and back of the train.
There is also an engine that looks like a baggage/mailcar.
It has no windows or area for a engineer. It is just a engine/drive car to work in tandem with another main engine.
It can not be use by itself.

Answer 9

Because dielectric [diesel and electric ] locomotives have 3000 horse power and are designed to pull 15,000 tons from a stand still. The big diesel engine in a locomotive of this type is basically a huge electric generator that supplies power to individual electric motors on each axle to provide massive pulling power. P.S. That was not a goofy question.

Answer 10

When you have that many cars, most of them are empty. But, lets say, they are loaded and heavy. The point is that a locomotive is EXTREMELY powerful machine. How can it pull so many cars? It has enough power to do it. Your little Honda Civic can pull maybe two or even three other Honda cars on a flat road. Can it do it? If it has enough power, it'll do it.