PRR Duplexes and Experimental Engines ( S1, S2, T1, Q1, V1 etc.)

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Posted by Jones1945 on Thursday, July 26, 2018 10:39 AM

Overmod

 A good story also involves a certain lack of interest in the riding characteristics of the trailing consist; admittedly I have nothing but anecdotal evidence, but even the best PRR business cars were increasingly hard-riding as slow as 110mph, worse than the locomotive, and it is hard to believe that a long Trail Blazer coach consist even with Dave Klepper's favorite homemade lightweight coaches would have produced tolerable riding at the speed Haas claimed.



That's a very good point, not until 45 (or later?), the first batch of post-war light weight coaches and sleeper arrived and were put into service. Before that, the Trail Blazer used a full set of rebuilt P70 cars with the original truck. I remember I read a story that in UK 1938, when the streamlined "Coronation Scot" reach 113mph, all the foods or drinks carried on the plate by the waiters in the diner were thrown all over the place (haha), and many China in the kitchen car were broken because of the hunting oscillation effect ! S1 was a preferred engine for hauling The Trail Blazer, I wonder how fast could those rebuilt/betterment cars can handle. But compare the massive size of the boiler and total heating surface area with T1s, if the latter can haul 800-1000 tons at 100mph or above, I believe S1, even without the poppet valves and is much heavier, should be capable to go at least 110mph. A German source says it can go around 120mph, I do believe it can, but not went that fast every day.
 
P70KR car #4269 used on The Trail Blazer, how fast it can handel? Umbrella (HAGLEY DIGITAL ARCHIVES)
P70KR used by The Trail Blazer until 1946

Overmod

It is possible to model the S1 in software and do multiphysics and kinematic analysis on the chassis to determine its stability and freedom from resonant couples (as was done, for example, for the German 05 class which had a calculated severe emergent critical speed close to 122mph, perhaps explaining why a run to outdo Mallard was never made).  



I am actually doing something like this with my daughter's video game "TrainZ" simulator, which allow me to config the 3D engine as realistic as I can, but anyway it is not a professional software, it's just a game which worth $30!

(S1 and T1 6111 in the game "TrainZ")
PRR S1 and T1 in video game

Overmod
The Q1 is interesting because it was intended as the 'modern' follow-on to the M1 (the 'performance envelope' specifically chosen to be 5/4 greater in capacity and in speed according to records preserved at the Hagley in Delaware) in the presumed higher-speed world of future Pennsylvania....... It is valuable to consider in particular why 77" drivers were used here,.....


For me, Q1 is not only interesting, but I also consider it one of the most beautiful steam engine ever built by PRR. I don't understand why many consider the 77" drivers were too large for a freight locomotive, Q1 was built during the war when construction of passenger steam locomotive was limited (or banned temperately ?), officially it was a new design for fast freight service but I agree with you that it was intended to be the new "M1" which was supposed to be a dual service engine (at least it could switch its roles) . Q1 was a larger streamlined, next-gen version of M1 which was probably inspired by the Grand Trunk Western 4-8-4. The U-4-b class was also a duel engine with 4 set of 73" driver and streamlined casting. I can understand why Q1 was streamlined and using such a large diameter for (express) freight service. Unfortunately, Q1's serving details is also very rare...... I wonder If it was a 4-6-4-6, carry a larger firebox would have helped.


Streamlined Yeah 70+ inches Drivers Yeah Dual Service  Yeah 

Grand Trunk Western


Overmod
A considerable effort was made to preserve the S1 'Big Engine' for the collection, it being arguably the most famous and recognizable PRR engine aside from 7002 and 460.  



Thank you very much for reminding me that! When S1 was retired, it was just one year after World War II...... One year after it was sent to the torch in 1949, another war began in the far east....... I always tell my friend that If I was PRR HQ, I would at least do some experiment like applying a newer model of the poppet valve and roller bearings on S1 after its first retirement in 46, its massive firebox and boiler shouldn't be wasted like this. Imagine S1 was sold to some 3rd world countries for express service, I believe she is still in service today. : )

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Posted by Overmod on Thursday, July 26, 2018 6:29 AM

M636C
The main "rumour" about 6100 is its claim to have run at 141 miles per hour. This is definitely unproven and likely to be false since it is based on one man's estimate of times.

We've discussed this fairly extensively in the past, and I attempted to verify the 'supposed' story by contacting the FRA to determine what, if any ICC "police" action was taken (the high-speed run was supposedly made on the Trail Blazer in 1947 prior to enforcement of the ICC speed restrictions imposed after Naperville).  There is no Government record of this (and no formal enforcement at the time) but we should recapitulate some of the details.

The story is attributable to Arnold Haas, who is better known as a NYC man ... one who is on record as having seen Niagaras regularly exceed 120mph in regular service, so make your own assessments.  The mentioned speed is not 141mph but 141.2, which should make all you non-metric railfans highly suspicious that this is in fact a converted number from a more 'round' Germanic speed, even before you start looking at likely observation error for recording that speed using the watch and milepost method (the speed recorder for 6100 pegging higher than other PRR engines at 110, the T1s in particular being 100mph, about which more later, so no way to observe 'directly' and no Valve Pilot fitted to either engine).  A good story also involves a certain lack of interest in the riding characteristics of the trailing consist; admittedly I have nothing but anecdotal evidence, but even the best PRR business cars were increasingly hard-riding as slow as 110mph, worse than the locomotive, and it is hard to believe that a long Trail Blazer coach consist even with Dave Klepper's favorite homemade lightweight coaches would have produced tolerable riding at the speed Haas claimed.

It is possible to model the S1 in software and do multiphysics and kinematic analysis on the chassis to determine its stability and freedom from resonant couples (as was done, for example, for the German 05 class which had a calculated severe emergent critical speed close to 122mph, perhaps explaining why a run to outdo Mallard was never made).  There are some details that would need to be addressed to make the locomotive properly stable on contemporary PRR track west of Crestline, particularly the lateral on the lead truck and on the first driver pair; to my knowledge, this received nothing like the attention the T1s did in the period between 1946 and 1948.

The Q1 is interesting because it was intended as the 'modern' follow-on to the M1 (the 'performance envelope' specifically chosen to be 5/4 greater in capacity and in speed according to records preserved at the Hagley in Delaware) in the presumed higher-speed world of the future Pennsylvania.  Remember that this was in the era of the B&O George Emerson and the ATSF 6-4-4-4 proposal, and all three of those designs essentially relied on divided drive to get around conventional balancing limitations rather than using later approaches like close-inboard Timken roller rods (and the ability of disc centers to handle the additional angling balance for the heavier bearings used with them) and Glaze-style balancing.  It is valuable to consider in particular why 77" drivers were used here, but 69" on the vastly more capable Q2s (which among other things had a rigid wheelbase shorter than any ATSF 2-10-4 higher than 5001 class, but I digress) that were designed for more expedient wartime speeds.  This while many of the J1-class engines, after "debugging", were getting 70" drivers...

A considerable effort was made to preserve the S1 'Big Engine' for the collection, it being arguably the most famous and recognizable PRR engine aside from 7002 and 460.  In the end it was the sheer (over)size of the project that tipped the balance; PRR was still having balance sheet problems and had prioritized acquiring more diesels stat, and the scrap value of the engine was over $35,000 (considerably more impressive converted to modern dollars).  Again much of the correspondence on this survives at the Hagley and it might make an interesting article for Classic Trains. 

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Posted by M636C on Thursday, July 26, 2018 5:58 AM

The closure of 39 World Fair was in October 1940

(From Wikipedia) The fair was open for two seasons, from April to October each year, and was officially closed permanently on October 27, 1940

Peter

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Posted by Jones1945 on Thursday, July 26, 2018 2:09 AM

Miningman

Classics Trains Photo of the Day a few years back. Always adored this photo... it is imposing, stunning and beautiful, even mysterious and haunting. Forum memeber David Klepper saw it in person when it was brand new and showed off at the 1939 Worlds Fair. 

20140401

This is the one and the only one photo of S1 taken during snowy day, very rare and beautiful! I remember I read a story on a post about S1 was frozen during heavy winter, but the crews managed to start it up. I read forum member David Klepper's post, I wish we could see more first-hand stories or info like his sharing.

I always wonder why S1's pics and video are so rare, I believe I have seen more pics or videos of K4s #3768 than S1. 

M636C
I assume November 1939 was between the 1939 and 1940 seasons of the New York World's Fair...?

As was posted above, it did quite a bit of work on the Chicago end, and no problems were attributed to the Walschearts valve gear and piston valves...

Peter

The closure of 39 World Fair was in October 1940, I didn't know if S1 stayed there until the end or not. Smile Franklin poppet valves were planned to be installed on S1 when it was under construction in 1938 but due to some technical difficulty, S1 was off the hook! IF I was the PRR HQ, I would apply Franklin type B poppet valves on S1 after its retirement in mid-1946 instead of throwing it on the scrapheap, but PRR was not run by railfans anyway, and they were probably busy fixing their brand new T1s   Stick out tongue

(Another lazy photoshopped pic)
S1 racing J3

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Posted by M636C on Thursday, July 26, 2018 1:20 AM

I assume November 1939 was between the 1939 and 1940 seasons of the New York World's Fair...?

So they had to extract it by a fairly roundabout route and reinsert it for the following summer, as well as changing the lettering from "American Railroads" to "Pennsylvania" and back the next year...

As was posted above, it did quite a bit of work on the Chicago end, and no problems were attributed to the Walschearts valve gear and piston valves...

Peter

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Posted by Miningman on Thursday, July 26, 2018 12:50 AM

Classics Trains Photo of the Day a few years back. Always adored this photo... it is imposing, stunning and beautiful, even mysterious and haunting. Forum memeber David Klepper saw it in person when it was brand new and showed off at the 1939 Worlds Fair. 

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Posted by Jones1945 on Thursday, July 26, 2018 12:15 AM
Thank you, Peter. I have "Pennsy Power: Steam and Electric Locomotives of the Pennsylvania Railroad, 1900-1957" by Staufer, Alvin F, "Black Gold - Black Diamonds: The Pennsylvania Railroad & Dieselization" Volume 1 by Eric Hirsimaki and "Pennsy Streamliners: The Blue-Ribbon Fleet" by Joe Welsh, they did provide only basic information of them, but their official testing result and performance detail are nowhere to be found. There are some fragmentary stories about S1 and Q1 on the internet, but I want more than this. I have a feeling that the PRR was hiding something on these two experimental engines or maybe everyone was so busy working during the World War......so many questions unanswered.
 
Btw If the speed records of S1 above 100mph are all "fake", I can say I have reasonable doubt that its wheel slip problem was also exaggerated too. S1 as a prototype served on Fort Wayne Division for at least 5 1/2 years (1941-1946), almost equal to the T1s (1945/46 to 51/52) and its Factor of adhesion is very close to PRR Q2 and Santa Fe 4-8-4 "Northern" according to steamlocomotive.com, (I understand that the duplex design probably made the wheel slip problem worse compare to a 4-8-4 design), I wonder what the PRR did to deal with the wheel slip problem of S1? Did they just sit on their office chairs and did nothing? I believe they did something, if not S1 wouldn't have assigned to haul "The Trail Blazer", a money tree of PRR. Unfortunately, I can’t find any official record about this topic. Anyway, please feel free to share your thought here! Thumbs Up
 
PRR Q1 4-6-4-4

 

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Posted by M636C on Wednesday, July 25, 2018 8:43 PM

The main "rumour" about 6100 is its claim to have run at 141 miles per hour.

This is definitely unproven and likely to be false since it is based on one man's estimate of times.

However, if a steam locomotive were to run at 140mph, something like the S1 would be needed to do it. I'd want it to have a dynamometer car attached with more than one speed recording device....

The various "Pennsy Power" books all provide basic details of the S1 and Q1 and show them as built and as modified.

There is a good book in German "Record Lokomotiven" which covers locomotives credited with speed records, NYC 999, PRR E2 7002, DR 05 002, DR 61 003, LNER Mallard and it has a full chapter on 6100. I'll post more detail later....

Peter

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PRR Duplexes and Experimental Engines ( S1, S2, T1, Q1, V1 etc.)
Posted by Jones1945 on Wednesday, July 25, 2018 4:25 AM

Original message (April 2018):

I have been collecting photos, models and learning these two mysterious engines for about two years (another one is S2 #6200 turbine). I searched every corner on the web, but information about PRR Duplex S1 #6100 and Q1 #6130 are extremely rare. Take PRR S1 for example, I can't even find its total mileage of her entire career.

I know there are some good readings in a few issues of "Keystone" magazine about T1s 4-4-4-4, but content about S1, Q1 are very rare and brief. There is not even one article about S1 in the most reliable source like the "Keystone". Some books and web pages about S1 and Q1 are base on rumors and historically inaccurate. If you have any books, articles or files would like to recommend, please kindly let me know! Much appreciated! Thumbs Up

Updates (Dec 2018):

Thank you all who participated in this thread in the past few months, helping me to understand the history of PRR Duplexes and experimental engines in-depth. Please feel free to join the discussion, sharing your thoughts about these fascinating projects which might have changed the history of America's railroad industry. There are still a lot of missing links of these massive engines, your contribution is greatly appreciated  Thank you very much!

======

  • PRR S1 #6100 6-4-4-6 7200hp Duplex express passenger steam engine (Source: Wiki)

 

  • PRR S2 #6200 6-8-6 6900hp Direct-Geared steam turbine locomotive

 

  • PRR T1 #6110 4-4-4-4 6550hp Duplex engine (Hagley collections)

 

  • PRR Q1 #6130 4-6-4-4 Dual-Purpose locomotive (Hagley collections)



Suspect Q1's conceptual plan (Hagley collections)
Q1's conceptual plan?

 

  • PRR Q2 #6131 4-4-6-4 8000hp express freight Duplex engine

 


 

Books and Articles about T1

(Special thanks to forum member feltonhill for the list):

  1. Atkins, Phillip. Dropping the Fire, Irwell Press (1999), ISBN 1-871608-89-9, pp14-21
  2. Hirsimaki, Eric. Black Gold, Black Diamonds, Volume 1, Mileposts Publishing, 1997
  3. Burnell, Neil. "An Appreciation of the T1 - The Enginemen's Perspective," The Keystone (Autumn 2001, pp 19-59)
  4. Burnell, Neil. "The ‘Slippery' T1," The Keystone (Winter 2001, pp57-62)
  5. Burnell, Neil. Response to 2 letters, The Keystone (Winter 2002, pp11-13)
  6. Burnell, Neil. "A Reassessment of T1 6110 and 6111", The Keystone, Vol 37, No. 1, pp18-39
  7. Burnell, Neil. "The Case for the T1a #5547." The Keystone, Vol.39, No. 3, pp40-52
  8. Stephenson, David R. "Chesapeake & Ohio Tests the PRR T1". C&O History, May 2005
  9. Stephenson, David R. "T vs. J". The Arrow, November/December 2006
  10. Crosby, John R. "Last Chance," Trains (August 1993), pp 54-56
  11. Lamb, J. Parker. Perfecting the American Steam Locomotive, Indiana University Press, 2003, pp152-160
  12. Lamb, J. Parker. "Supernovas of Steam," Steam Glory, Classic Trains Special Edition No. 2, Fall 2003
  13. Meyer, Charlie. "What Derailed the T1," Milepost, Vol. 7, No. 2, Spring 1989, Friends of the Railroad Museum of Pennsylvania (FRMPA)
  14. Meyer, Charlie. "Tracking the Pittsburgh T1 Derailments," Milepost, Winter/Spring 1990, Friends of the Railroad Museum of Pennsylvania
  15. Meyer, Charlie. "Poppets on the PRR T1, Part 1 of 2," Milepost, November 1990, Friends of the Railroad Museum of Pennsylvania
  16. Meyer, Charlie. "Poppets on the PRR T1, Part 2 of 2," Milepost, April 1991, Friends of the Railroad Museum of Pennsylvania
  17. Meyer, Charlie. "Just How Slippery was The T1?," Milepost, July 1991, Friends of the Railroad Museum of Pennsylvania
  18. Meyer, Charlie. "So Quickly Gone-What Really Happened to the T1," Milepost, December 1991, Friends of the Railroad Museum of Pennsylvania

 


 

Trains forum post about PRR experiential engine:

  1. An assessment of the benefits of the application of Franklin valves on the PRR K4 and T1 classes:                              http://cs.trains.com/trn/f/740/t/272776.aspx
  2. 120 MPH T1:                        http://cs.trains.com/trn/f/741/p/259651/2923505.aspx
  3. PRR S1 & streamlined K4   http://cs.trains.com/ctr/f/3/t/92758.aspx 

 

Last updated: Oct 4, 2019

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