Who would win in tug of war Big Boy vs. EMD DDA40X?

These one of the two most bad as* units of all time, the only question i have is who would win in a tug of war?

The photographers

Anyone have these locomotives in ho, n, or any other scale? If you got dcc you can try it and let me know which one won!
This is a DDA40X for those who dont know!

THis might be the closest they will ever come to a tug o' war http://www.railpictures.net/viewphoto.p ... 739&nseq=4

I think the big boy would win. Doesnt the Big Boy have more horses in it?

dunno, it would be cool though

Horsepower is not the critical factor. It is more like weight on drivers and tractive effort. Remember, the Big Boy has several tons of tender to haul around, and has idlers. The DD-40AX has ALL of its weight on its drivers, but weighs less than the Big Boy. As a SWAG I would guess that the diesel would slowly pull away with the Big Boy. Big Boys were not particularly known for slipping drivers, as the Challengers were, but slip they did. At that point the skill of the Engineers would make the difference.

I agree with Alan. Of course, no officer in the UP Research and Mechanical Standards Department in their right mind would couple back ends of a Big Boy and a Centennial together and say GO.

They'd hook up a dynamometer car, such as Mobile Lab 210 (nee Pullman BALSAM FIR) to each locomotive singly, control for a common trailing weight, and let the test results govern.

As far as testing models, wrong answer. You're pretty likely to have very similar electric motors. Worse, weight on the driving wheels may or may note be in scale to the original locomotives. If you're going to do an analog test, you have to eliminate as many variables as possible.

Big loser would be the drawbar. Second biggest loser would be the Big Boy.

Seriously, HP is almost utterly irrelevant. Starting tractive effort is critical, and in this case diesels have a huge advantage over steam.

But a DDA40X doesn't have a huge advantage over a 4-8+8-4. It may not have any.

First question: are we talking about an actual DDA40X, which had 59:18 gearing?

Unless we modify it, the diesel's control system won't allow an instant buildup of tractive effort. If it takes, say, 10 seconds to build up full TE, the 4-8+8-4 might well outpull the diesel for the first few seconds. So we need to know what a diesel's TE is at minus-3 miles/hour-- will it be able to stop its backward motion?

By the way-- in a tug of war, the 4-8+8-4's tender will be an equal burden to each engine. Think of it this way: what if the tender weighed a million tons? Would that improve the diesel's chances of winning the tug of war?

As I said before, there is NWIH an Operating Department man would let this happen.

Any testing would be with one of UPs dynamometer cars.

I guess, though I need to cue "The Mamas and the Papas."

Would the fact that the big boy has larger drive wheels help? A larger wheel has more surface area on the rail thus inproveing traction.

John_Perkowski wrote:Of course, no officer in the UP Research and Mechanical Standards Department in their right mind would couple back ends of a Big Boy and a Centennial together and say GO.

John_Perkowski wrote:As I said before, there is NWIH an Operating Department man would let this happen.

No one said he would.

Trainman101 wrote:A larger wheel has more surface area on the rail thus inproveing traction.

Lots of fans will tell you high-drivered steam locomotives are more slippery than low-drivered. None of us knows anything about that.

Smaller diameter wheels will produce larger tractive efforts, larger diameter driving wheels will produce higher speeds.

well if you could find a rope or something that could be put up that much stress then wow. i think the dd40 would win simply because the amount of effort to get the thing to move would be less. release brakes, reverser in direction and bam. take off. big boy on the other hand probably takes a wee bit longer to go through the motions to move. oh and i don't think the size of the wheel matters for traction, pretty sure only a small portion of the wheel actually touches the rail, maybe 1 inch at most.