Train length?

Question

I've recently been on google earth and was looking at the railways in California. I am just wondering how long or how many carriages trains can have and if you have ever seen one. I live in Glasgow in Scotland and have never seen a train with anymore than 15 compartements. Thank you.

Answer 1

If you mean passenger trains, the biggest in America are 25 cars, 30 at the outside, and those are tourist/railfan (trainspotter) excursions.   Amtrak's biggest are 20 cars or so.    However, American passenger cars tend to be bigger than what you see in the U.K. -- just look at our Superliner cars.

Amtrak has a long history of adding freight cars to their trains.  

- Auto Train adds quite a few auto-rack cars carrying passengers' automobiles.

- Amtrak hauled the U.S. mail for a number of years, which amounted to several additional "AmBoxes" (boxcars upgraded to run in passenger trains) on many long-haul trains.  They even had a dedicated mail train in the northeast corridor, to which they added a couple of coaches and a sleeper (the "executive sleeper".) - yes, a sleeper in the northeast corridor.  

- Amtrak flirted with carrying carload freight on Amboxes.  They even added RoadRailers to the back of some Amtrak trains. However the freight railroads (on which Amtrak runs) really didn't like that!

Answer 2

I was amazed when i went to California last year. Spent a few days at Lake Tahoe. On the way i passed a train which seemed to go on for as far as i could see, it was massive.It went through a little town called 'Truckee' (really nice quaint place), maybe if you do a search on this town you might find out more. Sorry dont know haw many carriages were on it, wish i had of counted them now.

Answer 3

Oh ho!  Another Scottish spy looking for our top secret train specifications, eh?

Answer 4

When you say carriages, I think you are talking about passenger trains.  Passenger trains don't usually get above 10 cars in length, even at rush hour, for local commuter traffic within a city.  Long distance rail is handled by a government company called Amtrak, and their trains have been getting shorter over the years.  It's possible to see a train that is 15 cars long, but usually you are talking 5 cars or so for long distance trains between cities.

Freight trains can indeed be 10000 feet long or more, which translates into about 200 cars or so.  Over flat areas, like between New York and Chicago, the train length can get as long as 14000 feet.  In a more mountainous region, like California can be, 9000 to 10000 feet is about the max, although it's more a matter of train weight than length.  If the train weighs too much, the pulling power needed to move the train exceeds the strength of the couplers, and the train will be ripped apart.

Answer 5

Trains in North America can have 120+ cars and be over a mile and half long.

Answer 6

Looooooooooong.......

The person who mentioned the correlation between air pressure and length is quite correct.  In the early '70s the Southern Pacific tried "repeater" cars. which were basically box cars with air compressors aboard and valve gear that told them when to pump and when not to, so that the brakes would not unintentionally release.  It looked good on paper but they failed to perform well.

But, the carriers have figured out a way to get around that, in the form of "Distributed Power."  Unmanned helper engines are placed toward the rear of the train, such that of the tonnage they handle, they are entrained to push one third and pull two thirds.  This configuration keeps the multiple unit consists from pushing the cars ahead off the rails.  They are operated by the road engineer via radio communication, and their air-brake systems are "cut in," or operative.  This allows for many more feet of train to be properly charged at the rear.

When operating "single" however, the length becomes an issue once again.  The longest I ever operated in "grade territory" was just shy of 9,500 feet, including power.  Of course, where there is grade territory there is a mountain, and where there's a mountain their is frigid air.  Cold has a major impact on charging the rear of the train to the proper pressure, so tonnage is usually reduced during extremely cold winter months.

If you need more information on the air-brakes visit my 360 blog and follow along starting with Hoghead's Highball No. 1.  It may be of interest to you.

Answer 7

If I remember correctly from talking to a train supervisor a few years ago I think it is 9000 Feet.  They are limitied by how far the air compressor on the engines can push the air.  Even at that full air doesn't reach the back cars so they have to put the empty/light cars in the rear.

Answer 8

There are very few passenger trains in the US. What there are are not significantly longer than the longest you might encounter in the UK. I assume the trains you have seen on google earth are freight trains - which most certainly are long! American freight waggons are all long vehicles which from above would look like passenger carriages. In Britain it would be unusual for a freight train to be more than about 2000 tons. In the US 15000 tons might be a bit nearer the maximum! To haul loads like this would require perhaps 7 locomotives distributed at front rear and centre of the train. The main factor encouraging such vast train lengths is the distances involved in travel across the US and the fact that most of the network is single track, limiting capacity. Therefore it makes sense for each train to be as long as possible to economise on track occupancy. Whilst the US passenger train is largely a thing of the past due to air and road competition, the US railroads are still very busy with freight traffic, since the cost of rail freight is very competitive.