Does anybody have any hard numbers on how quickly a railroad locomotive can cover the quarter-mile from a standing start?
I’m particularly interested in modern diesel freight locomotives, but times for anything that rides on rails would be pertinent (although I’m definitely not interested in vehicles like the ones in the center and right-hand pictures on this page)
There’s a lot of figures for modern electric passenger trains here, including:
The German ICE1 reaches 100kph in 66secs and 900 metres, and 250kph in six minutes. The British Virgin Pendolinos do 0-60mph in 60s, and the Finnish Pendolino 0-200kph in just over three minutes.
This page gives a typical light-rail acceleration of 1.2-1.3 m/s2. A typical London Underground train is about 140yds, and I’m sure one of the London dopers would be happy to time how long it takes for it to clear the platform…
I can’t find anything for freight trains, but I guess the acceleration isn’t nearly as important as the power that can be delivered, and the efficiency.
Australian Co-Co (six powered axles) Victorian Railways’ G class diesel electric freight locomotive
Scroll down the page right to the end for the specs (if you bother to read the whole thing, comparisons to a “Commodore” refer to an Australian V6 rear wheel drive General Motors family sedan motor car).
This locomotive is a fairly typical freight machine as used on many of the world’s railways.
You do realize that this is completely, utterly of absolutely no interest to the railroad?
Railroad locomotives are designed to move large amounts of freight long distances at moderate speeds, as efficiently and cheaply as possible. They are designed not for spped, but for pulling power with least fuel use.
When you’re spending days hauling a mile-long train of coal cars from Powder River, Wyoming nearly 1,500 miles to Detroit Edison*, you really don’t much care how long it takes you to go that first quarter mile!
Well, yeah, but they have tugboat races along the Seattle waterfront once a year, and let me tell you, those things ain’t built for speed, either.
I think it’d be cool to see two of these massive locomotives lined up, engines roaring, engineers watching the light stand, and then blasting down the quarter mile. (Well, “trundling down”…) And just imagine the parachutes it would take to slow them down.
This is an extreme sport I could really get behind.
Probably true for the example you cite (long-haul freight train). But when a vehicle must make many stops & starts and keep a schedule, it becomes important to know what acceleration to expect. And it would not be useless to know whether a big train will take 10 or 15 minutes to reach full speed.
[QUOTE=Xema]
Probably true for the example you cite (long-haul freight train). But when a vehicle must make many stops & starts and keep a schedule, it becomes important to know what acceleration to expect.
Absolutely. It’s not by coincidence that the easiest figures to find (that I posted above) are for electric passenger trains, both high-speed and commuter. There’s this current thread that has more information than I could give about such things.
Yes, it would be useless, in everyday railway operations. The important information is where it is, not its speed. That’s been a crucual element of railway signalling for, ooh, 150 years.
It’s a relief that you aren’t expected to know both, here on the Heisenberg express.
I’ve noticed that where something is can often be a function of time and its speed.
[::Nods to yabob::]
But how do you get the train into a dress? 
I don’t suppose you’re counting maglev systems? On the 25-mile test track up in Yamanashi they got full-sized trains up to 350mph last year with an acceleration, according to the engineers, of 2.5 times that of ordinary trains.
I think it’d be cool to see two of these massive locomotives lined up, engines roaring, engineers watching the light stand, and then blasting down the quarter mile. (Well, “trundling down”…) And just imagine the parachutes it would take to slow them down.
I think that’s what the OP was about: turning her over, letting her warm up, Wiping the throttle by setting it to Notch #8, letting the CAT engine spool up to max allowable RPM (watching the flames shooting from the exhaust stack), and then releasing all the brakes.
It would certainly be an earth shattering noise, but I doubt you’d get acceleration that would push you into your seat
What about switchyards, where locomotives will stop and start a hundred or more times a day? I assume the quicker they get the cars in the appropriate places, the better that is for the company, so a standing-start quartermile or at least standing-start accelleration under various loads could come in handy for figuring how long it would take to do their jobs.
Rarely would such operations be done on a just-in-time basis. And the time savings from a faster acceleration would be very small, compared to the overall time (don’t forget that much of the time lost would be through waits for the signalling system, etc)