Allis-Chalmers Pulled a TRAIN!!!

In this ad for a 1977 AC 7080 the tractor pulled a train consisting of thirty cars and a caboose!!!

A whole new concept in "tractor pulling"!!LOL

Neat add, but don't let it glaze your eyes.

About ten years ago, my Dad pointed to an ad in a '50's Popular Science magazine, showing Charles Atlas pulling a railcar with a rope... saying 'That was one strong guy'.

Yep.  Sure.  NOT!

At the time, I was teaching railcar maintenance all over the US, Canada, and overseas.  Several times a day, we'd move railcars in and out of the shop... pushing them by hand.

See, the rolling resistance of steel wheels on straight steel track, is incredibly low... and with good roller bearings on those axles, it doesn't matter how heavy that railcar is... it will roll with the slightest push... it's just that it takes a steady push and patience.  We used four guys to spot 90-ton subway cars (with 4 400hp electric motors on 9:1 gearboxes) into the shop for maintenance.  We'd apply release air, then just lean on the car... and in 15 seconds, it'd be moving slow, another 15 seconds, it's rolling at a walking pace.

One of the biggest concerns here, though, and I taught it EXTENSIVELY in our safety classes, is that the car, although moving slow, possesses incredible inertia, and that wheel-to-rail interface, as well as inter-car or obstruction contact, is deadly.  You can be working under a railcar, with one hand on a running rail, twisting a wrench, and leaning on the car, and if not chocked, it will start rolling ever-so-slowly, and ever-so-quietly, and as soon as you realize that your hand is under a rolling wheel, it's too late... your hand will be gone, and there's nothing you can do to stop it.

Pulling the train with a tractor is no big deal... that farm tractor's tractive effort is WAY more than required, particularly on straight level track.  Realize that those agricultural tractor tires against the ties is considerably higher than a locomotive's steel wheels against steel rail.  The average thrust capacity of a locomotive of THAT VINTAGE is about 26% of it's weight... SO, if the locomotive weighs 200,000lbs, the drawbar effort available is limited to about 52000lbs.  It seems insanely wrong, but one horsepower is 33,000 foot-pounds per minute.  That means you're pushing 33,000lbs one foot, in one minute.  That means, at very low speed, that drawbar effort equates to very little horsepower (and by definition, that is true).  That 2,000hp locomotive seems pretty weak...  but keep in mind that the locomotive's power is limited by wheel slip... that applying 52,000lbs of draft to the consist at 60mph is the 'horsepower' equivalent of 52,000lbs 5280 feet in one minute... so... mathematically capable of 8200hp.

This doesn't make sense, does it?  Horsepower ratings for locomotives don't make mathematical sense... of course, nor do tractor horsepower ratings.  If you put 180 horses in a team, would they equate to the same capacity of that tractor?  (I doubt it).

The locomotive's advantage over the tractor... if the locomotive is mechanically-controlled diesel-electric, it can apply it's full drawbar effort starting at 0 speed, and keep a constant draft force regardless of speed... and can do it indefinately.  The tractor, however, cannot do that if it has a mechanical driveline and no torque converter.  If it's hydrostatic, or uses a torque converter, it can start at zero speed, and operate that way for a little while before overheating the fluid.  Once the consist starts moving, it'll accelerate to whatever speed the tractor can manage.

Here:  http://arvadahoundz.com/images/chama_little_gas_loco.jpg
If I remember correctly, these little Chamas used either a Minnie-Mo tractor or Hercules industrial engine driving a generator, which drove one 30hp DC traction motor on each axle.  Easily shuffles 3 cars around tight bends in railway yards, so they'll pull 10 on straight level track.

Here's a Shuttlewagon:  Easily capable of a 31-car straight track pull-
http://www.shuttlewagon.net/315.html

I'd be confident that a WD, WD-45, and a D17 would all be capable of making that pull... but it'd be best to run without wheel weights, so that you could let the tires take the initial slip, rather than dragging the clutch.


Edited by DaveKamp - 16 Sep 2010 at 11:05pm

And then in most territory, the river crossing is going to be the low spot on the line, so its down hill to the trestle, so the train may have pushed the tractor.

Gerald J.

DaveKamp wrote: Neat add, but don't let it glaze your eyes. About ten years ago, my Dad pointed to an ad in a '50's Popular Science magazine, showing Charles Atlas pulling a railcar with a rope... saying 'That was one strong guy'. Yep.  Sure.  NOT! At the time, I was teaching railcar maintenance all over the US, Canada, and overseas.  Several times a day, we'd move railcars in and out of the shop... pushing them by hand. See, the rolling resistance of steel wheels on straight steel track, is incredibly low... and with good roller bearings on those axles, it doesn't matter how heavy that railcar is... it will roll with the slightest push... it's just that it takes a steady push and patience.  We used four guys to spot 90-ton subway cars (with 4 400hp electric motors on 9:1 gearboxes) into the shop for maintenance.  We'd apply release air, then just lean on the car... and in 15 seconds, it'd be moving slow, another 15 seconds, it's rolling at a walking pace. One of the biggest concerns here, though, and I taught it EXTENSIVELY in our safety classes, is that the car, although moving slow, possesses incredible inertia, and that wheel-to-rail interface, as well as inter-car or obstruction contact, is deadly.  You can be working under a railcar, with one hand on a running rail, twisting a wrench, and leaning on the car, and if not chocked, it will start rolling ever-so-slowly, and ever-so-quietly, and as soon as you realize that your hand is under a rolling wheel, it's too late... your hand will be gone, and there's nothing you can do to stop it. Pulling the train with a tractor is no big deal... that farm tractor's tractive effort is WAY more than required, particularly on straight level track.  Realize that those agricultural tractor tires against the ties is considerably higher than a locomotive's steel wheels against steel rail.  The average thrust capacity of a locomotive of THAT VINTAGE is about 26% of it's weight... SO, if the locomotive weighs 200,000lbs, the drawbar effort available is limited to about 52000lbs.  It seems insanely wrong, but one horsepower is 33,000 foot-pounds per minute.  That means you're pushing 33,000lbs one foot, in one minute.  That means, at very low speed, that drawbar effort equates to very little horsepower (and by definition, that is true).  That 2,000hp locomotive seems pretty weak...  but keep in mind that the locomotive's power is limited by wheel slip... that applying 52,000lbs of draft to the consist at 60mph is the 'horsepower' equivalent of 52,000lbs 5280 feet in one minute... so... mathematically capable of 8200hp. This doesn't make sense, does it?  Horsepower ratings for locomotives don't make mathematical sense... of course, nor do tractor horsepower ratings.  If you put 180 horses in a team, would they equate to the same capacity of that tractor?  (I doubt it). The locomotive's advantage over the tractor... if the locomotive is mechanically-controlled diesel-electric, it can apply it's full drawbar effort starting at 0 speed, and keep a constant draft force regardless of speed... and can do it indefinately.  The tractor, however, cannot do that if it has a mechanical driveline and no torque converter.  If it's hydrostatic, or uses a torque converter, it can start at zero speed, and operate that way for a little while before overheating the fluid.  Once the consist starts moving, it'll accelerate to whatever speed the tractor can manage. Here:  http://arvadahoundz.com/images/chama_little_gas_loco.jpg If I remember correctly, these little Chamas used either a Minnie-Mo tractor or Hercules industrial engine driving a generator, which drove one 30hp DC traction motor on each axle.  Easily shuffles 3 cars around tight bends in railway yards, so they'll pull 10 on straight level track. Here's a Shuttlewagon:  Easily capable of a 31-car straight track pull- http://www.shuttlewagon.net/315.html I'd be confident that a WD, WD-45, and a D17 would all be capable of making that pull... but it'd be best to run without wheel weights, so that you could let the tires take the initial slip, rather than dragging the clutch.

The question in my mind is how did they get permission from UP to do that?

Years ago we wanted to get in the business of loading unit trains. The guys that knew the business wouldn't tell us. There was a Trackmobile on an auction on Saturday and we had 25 cars coming on Monday. We knew nothing about how to air up a car to use the brakes.
It doesn't work well to jam an Allison transmission in reverse to stop 3 - 4 cars.  That was a hard learning curve. We did finally get to the point of having origination weights and grades and a switch engine. Now, it is just always overnights, holidays, weekends, storms. Whenever guys don't want to be there doing it.

I agree with Dave too. It would be impressive if the tractor was pulling those cars uphill.

AllisChalmers37 wrote: DonDittmar wrote: HagerAC wrote: I got the promo video that shows that, it is an awesome video. I have the same video. its a good one   Could you post this video. I would like to see this.

Its on VHS. If I had a way to get it on my computer I would be glad too

If you look at the text in the ad, it mentions the "slack" between each cars couplers ("coupling hit coupling, down the line"). The tractor actually only starts one car moving at a time. When the "Slack is in",
the cars are bunched together and one begins to move, then after is has moved several inches, the next car begins to move, and so forth until all are moving. But still a neat piece of advertising. Bob@allisdowneast

Now let us remember...It looks impressive...therefore it IS impressive...to the untrained eye...Don't ever tell your DEERE or IH guys that info when showing them this pic!!!!

Wow! A whole 3 dB reduction in niose level! That's about the minimum change you can detect by ear though its reducing the noise power to half. The measurement probably isn't repeatable to 3 dB without hours of averaging.

Now for comparring factors they neglected two that in the long run are vital. What's the fuel consumption at full and partial load and how many hours will each tractor last? 4000, 8000, 12,000? Or how many hours to the first rebuild? Then will that rebuild be engine or transmission?

Gerald J.

Averaging is how they always do it when testing sound levels. Just like testing horsepower. Back in their day Allis had good resale value and they were number one in combine resale back then. 

whew!

My cousin worked for the Railroad at Walden, CO (he laid the planks along the rail so they could hook up to the train) when this happened-he told us that they had to apply the brakes on the train cars as the tractor was pulling them downhill-just want you to have all the facts.  We are Allis fans and think they are the best tractors ever made however this post isn't representing all the facts.

SbarBRanch wrote: he told us that they had to apply the brakes on the train cars as the tractor was pulling them downhill...

It is S.O.P. to have brakes applied when descending into a non-locomotive draft unit, especially when the draft unit does NOT have gladhand couplers for charging the brake pipe.  This is an AAR recommendation for yard and hostling operation, and when on mainline track, the FRA has a host of requirements in similar categories.

Regardless, if one looks closely at the photo, you'll see visual proof that the trestle crossing is not a decent path, and like most low-elevation trestles, the trestle deckway and trestle approach is superelevated with respect to the roadway.  This is common ROW engineering procedure, both to protect the trestle from rapid erosion in the event that flash flooding occurs, and to allow short consists to be parked atop the trestle to stabilize it during floods.