Pennsylvania RR T-1 modification?

Thank you very much - this is very helpful.

I thought that I had read in more than on place that the Q's had a factor of adhesion >4.0 and the T1<2.0, which led to my question. Thanks for the correction.

Although discussed above, would connecting the two engines have made a difference?

Did the Pennsylvania ever consider connecting the engines?

VA RAIL FAN

If it were possible to connect the two engines, it would have made a decided difference. The T1 would have become a somewhat unconventional 4-8-4, with a 4-axle engine rather than a pair of 2-axle engines. IMO a large number of handling problems would have been eliminated. However, no improvement would have been made in the complexity and inaccessibility departments - one inside poppet valve gear box replaced by a pair of inside connecting rods.

AFAIK, PRR never considered connecting the two sets.

Thanks, Feltonhill, for answering my implicit question:
>>>There was only one throttle and cutoff on the T1.
...
I have read (I think in a "Trains" article from the 1960s about French steam) that some French compound steam locomotives had double cutoff controls which allowed the engineer to adjust the relative amounts of work done by the high and low pressure components of the engine. (These were NOT duplex drive: all driving axles coupled.) Apparently this required a very high level of engineer training to use effectively: as I recall, a French railwayman did a fair bit of classroom work before being promoted to driver of a steam locomotive. ... Perhaps the Pennsylvania would have obtained better results from their T1 and Q2 locomotives if they had been able to invest in a training program to ensure that all engineers using them knew the fine points of their operation! But probably this would have been unfeasible given the realities of the post WW II labor market: after all, there was a similar problem and similar failure to solve the problem when it came to T1 and Q2 maintenance.

It seems to me that there would have been a relatively simple option to help in the slipperyness of the drivers... reduce the pistion diameter.

After finding the drivers had a tendancy to slip, I would have brought one unit into the shops (or grabbed one on the assembly shop floor) and had new 1/2 thick steel liners pressed into the cylinders, reducing the cylinder diameter by an inch. This would have reduced piston power as well as increased engine weight, granted not much.

One thing I never understood about the T1's: their cylinders appear to be roughly the same size diameter as a run of the mill engine. except your average engine's pistons were coupled to eight points of contact to the rail, as well as several thousand pounds more running gear. Without doing the numbers and computer simulations, I'd say that piston surface area should have been reduced to roughly 66% of a comparable 2-cylinder's area.

Supposedly the duplexes' reason for being was to reduce dynamic augment by reducing the weight of the rods, thereby the weight that had to be balanced and cross-counter-balanced. But leaving the cylinders the same size would be putting the same amount of power into half as many tractive adhesive points, doubling the power applied to the rail per contact point. Seems to me they should have been slippery. With the success of the high-speed berks, Class A's and H8 alleghenies, the 2-wheel lead truck seems to have been relatively safe for passenger service. Perhaps a 2-4-4-4 would have been a better arrangement, placing more adhesive weight to the drive axles.

Thoughts?

I'm not home at the moment, so I don't have access to my data base, but the C&O tests as described by Don Ball were somewhat erroneous. Based on considerable first-hand evidence that he did not include or did not have access to (memos from the men involved in the tests) the T1's had no adhesion problems, and their difficulty in starting trains were (1) in Waynesboro, the T1 (5539) would not start the train, but it didn't slip as documented by both C&O and PRR personnel in written comments following the tests; (2) the start at Craigsville was also documented by PRR's representative as a difficulty in staring the train, and no slipping was encountered in the process. Don Ball's account was almost correct, but somehow he (or someone advising him) couldn't resist editiorializing on the event, and we're stuck with the result. The T1 was no worse than any other locomotive in competant hands. It's just that there were fewer hands competant enough to get past their catch points. If anyone reading this has ever been involved with high performance cars, you'll know what I mean. You either learn how to drive them, or they will teach you in short order!! The PRR T1 was just such a device!

I was reffering to the commonly held conception that the T's were slippery even on the PRR's railroad. They have a netorious reputation for slipping. I can't beleive this all stems from one person's misrepresentation of a few test runs on a foreign railroad.

At least nine T1s had their cylinders reduced to 18.75". So far the only source I (and several others) have found regarding the T1's cylinder reduction is in Vernon Smith’s book, One Man’s Locomotives, at pg 161. There he lists the following nine numbers:

6110, 6111
5521, 5522, 5524, 5531, 5532, 5536, 5540

The two prototype T1's had definite adhesion problems brought on by a variety of design flaws. These were enumerated in several reports written by Norm Suhrie to his superiors in 1942-43. For example, the suspension equalization took weight off the front engine on curves, which led to stalls. The sand pipes were fixed by brackets on the frames. Since #1 and #3 axles had lateral motion devices, the sanders followed the frame on curves and dropped sand on the ties instead of the rail. Both these defects led to operating problems and were corrected.

Later in 1944-45, there are many surviving reports of 6110 and 6111 being dispatched with plugged-up sanders, or sanders not aimed properly. One PRR test rep got fed up and threatened to refuse 6110 or 6111 for service; the roundhouse fixed the problem in 30 minutes. C&O commented about mis-aimed sand pipeson both 5511 and 5539 because they had to correct this defect. There are almost always extenuating circumstances to consider.

The T1 had a reputation for being slippery in part because of maintenance defects and also because some engineers never got the hang of operating them. They were very unforgiving locos. not at all like the K4. The T1's slipping was not imaginary, but it was not uncontrollable either. IMO they were not designed with PRR's less-than-perfect servicing and operating conditions in mind. The other standard classes were.

Considering that I'd never heard that the T1 was tested on the C&O, were the T1's relatively slippery even on the PRR?

If PRR took the time and expertice to develop the other classes with sufficient adhesion to overcome the inherant unequal torque of steam tech, one would think a few more weeks on Junita's drawing board would helped to have elieviated the issue.

The T1's were not considered slippery during the C&O and N&W tests.

There's an article that appeared in C&O History May 2005. See my earlier post on this thread 9/5/07.