There's something that puzzles me. If dynamic augment was the problem Baldwin thought it was-enough to pour an awful lot of R&D and Design money into-for a total order of 52-then the question begs-and bear with me-I have to wonder:

1.) Why, instead of having two large cylinders powering all drivers, why didn't anybody have individual cylinders for each driver? Would the added mechanical complexity not been justified by any advantages?

2.) If that wasn't possible, how about connecting the drivers through geared transmissions rather through side rods. Could internal gears have been any worse to maintain than say, rod brasses? Was there a mettalurgical or lubricational issue.

2.) Why didn't BLW & PRR interconnect the front and rear drivers through a gearbox-- as much as the article disputes the T-1's slipperiness-there's a couple of old films I've seen that show one set spinning away. Of course assuming slipperiness was an issue was that related only to the fact that there were two seperately powered sets of drivers or was it more related to an optimistic factor of adhesion.

Superheater,

I'll have to get back on this bit later today. Didn't want you to think I was ignoring your questions.

Initial reactions -

I believe B&O proposed a steam motor type of arrangement for each axle of a 4-8-4 sometime in the late 1930's (never built). I also recall there was a German locomotive brought stateside for analysis after WW2 that had a similar arrangement. There are photos and a story about this loco on the web someplace. Recall seeing it.

All of the interconnection suggestions add to mechanical complexity and additional maintenance inaccessibility. The T1 already had troubles in these areas. A 4-8-4 like the NYC Niagara seemed to solve most of these problems without deviating from conventional simple design.

I've seen the video of the T1 slipping going through the yards in East St. Louis. In contrast, how about the very dramatic footage of a T1 climbing the grade up the bridge at St. Louis and not missing a beat? I've also seen a video of 3985 slipping almost to a stall because first the front, then the rear engine slipped. Equally in contrast, 3985 pulled away from the problem very nicely after getting her feet. Good video clips do not necessarily mean typical or statistically normal operation

Actually the T1 was built to a relatively conservative FA just like a 4-8-4, except it wasn't. It was undone by the extremely low pressure losses to the cylinders, the low back pressure and only two coupled axles per engine set. The high pressure steam resulted in about 92-94% of the boiler pressure getting to the cylinders, not 85% as is normally estimated. Plusses became minuses, etc....

Be back later this evening (I hope). Other obligations this afternoon.

Second installment of reply -

The B&O steam motor 4-8-4 (or 4-2-2-2-2-4) is described in the book, B&O Power, by Lawrence W. Sagle (1964), @ pg 291. There's a sketch of it on pg 308. The project started mid-1937. The boiler was partially built, and one of the motors was manufactured and tested. The project was abandoned and the locomotive was never completed.The boiler was used for #5310, a P9b 4-6-2

The German steam motor 2-8-2 is described here:

http://www.pernet.net/~james1/v-8/v-8steam.htm

It was brought to the US in 1945 (Ft. Monroe) but eventually scrapped at Ft. Eustis in 1952.

As part of the ACE test program in 1985, in partnership with the AAR we instrumented a section of track outside Charleston,W.Va. to record the dynamic augment forces caused by the 614(under different loads and throttle settings) and the diesel fleet. Very much to the shock of the engineers involved the results showed that Lima had done such a good job balancing the 614(and making max. use of the roller bearing technology) that she was no more punishing to the track structure than the diesels and as a matter of fact at the lower throttle settings when pulling max. tonnage trains 614 was LESS demanding on the track than the diesels! Totally counter to all the conventional wisdom and old wives tales we've all heard so often.
I'm not sure but I believe the AAR testing folks published the results somewhere in 1986??
Ross Rowland

Last installment -

The T1's alleged slipperiness was related to a variety of things. However, the most important were the 2-axle engine sets and joint control. Any 4-cylinder loco has the problem of joint control of two engine sets, but most have 3 or 4 coupled axles per set. These arrangements are not as sensitive to rail conditions as a 2-axle engine set. The T1 was the only modern loco with a pair of 2-axle engines under the control of one throttle. As I pointed out in the article, this setup would always be more prone to slip than a 4-8-4 of similar capacity. However, the reason I came down so hard on the slipping issue was the amount of hype that has surrounded this trait. Test after test that I've found (these are original source documents from PRR, C&O and N&W, not unsupported hearsay) have not substantiated any adhesion problems with the production group of 50. Extensive PRR tests of the two prototypes run in regular service showed the same thing - after various modifications were applied from 1942 through 1945, they would do anything asked of them if handled in a competent matter. One example from late 1945 (have the original PRR report of this run) - T1 left Harrisburg with a 21-car passenger train. The entire trip was run in fog and rain. There were two slips recorded. There were no problems at any of the intermediate stops. That's it. BTW, it made up eight minutes on the run.

Most of the problems were caused by ham-handed operation and slip-shod maintenance. The T1 could perform, but.....

On the other hand, as noted above by Ross Rowland, a good standard 4-8-4 was not that hard on track, and with four coupled axles, they did not require as skilled a hand at the throttle as did the T1 when rail conditions were less than perfect (as they never are in the real world). This is what I was trying to get at the final part of the article when I said that the duplex concept no longer had a problem to solve. 4-8-4's evolved over the period from 1935 though the end of their production in 1950. As a result, the dynamic augment problem wasn't as much of an issue, and even at fairly high rotational speeds (maybe 400 rpm or so), steam handling wasn't compromised as severely as predicted. However, at higher rotational speeds, the four small cylinders of the T1 would process steam more efficiently than two large ones. The question was always - in what speed range does your passenger locomotive spend most of its time?

Now since Ross is also on this thread, let me ask this. How would you have liked to try your hand at one of the PRR T1's, say with a 15-car train, running a little late out of Ft. Wayne, John Crosby firing for you? Truly they must have been the Ferrari of steam.

The answer is I would have relished that opportunity either Eastbound or Westbound!! Wonder what she'd have ridden like on that track at 120 per??? Ross Rowland

When I read the report Sunday I could not help thinking that C&O was a railroad with a lot of articulated power. By contrast the PRR had almost none. I think that would give the C&O crews a faster learning curve because they were more familiar with handling this type of power than the PRR crews were. Being heavy handed with a locomotive that is a little slippery will not work under most conditions. Western Maryland's challengers faced a similar fate. Engineers were use to hauling the throttle wide open on their decapods with 75,000 pound driver axle loads and you just could not do that with a challenger until you had a little roll on the train and some sand under the drivers.

John Bohon

To paraphrase the story in "Trains" magazine" "Where's your pilot's license?"

Please do NOT stand close to the track!!!!!! Ross Rowland

One example from late 1945 (have the original PRR report of this run) - T1 left Harrisburg with a 21-car passenger train. The entire trip was run in fog and rain. There were two slips recorded. There were no problems at any of the intermediate stops. That's it. BTW, it made up eight minutes on the run.


Would you be able to share a copy of this? Be happy to reimburse you for any reproduction/mailinng costs.

I can paraphrase the source so everyone interested can read it.

This is from the Hagley Museum and Library, Wilmingon, DE, Accession #1810, Box 536, memo from C. K. Steins to H. W. Jones, 9/24/45

T1 6110, Train #75, 9/23/45, Harrisburg to Altoona with 21 cars, about 1550 tons. Left Harrisburg 6 minutes late, on time at Huntington, 2 minutes early at Spruce and Altoona.

Wet rail, raining, slight fog.

Slight slip leaving Harrisburg over switches where sanding was not permitted. One slip between Bell and Antis.

Started at Tyrone taking eight cars slack, no slip

Quote from last paragraph -

"This is a great performance from the standpoint of making a fast schedule with a much greater tonnage than the engine was designed for, and doing it on wet rail, when a K4 - with almost any train - would have done more slipping."