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

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Posted by Jones1945 on Saturday, January 18, 2020 2:49 PM

Overmod

I'd have been amused to see a completed Chicago New York Air Line Railway built out to double track with proper high-speed overhead power (probably catenary rather than improved pole) and the degree to which it would compete with heavy railroads throughout subsequent "likely history".  (My guess would be conversion to four-lane "Turnpike" at a fairly early date, following the example of the Pennsylvania Turnpike and possibly changing the course of the New York State Thruway as built.)  Unlike the South Penn, a CNYAL would have been inherently straight-graded and have few curves...

In case our younger reader missed our discussion about the CNYAL eariler:

"I am in!"

https://chicagology.com/transportation/airlinerailroad/

A farsighted project like the CNYAL would have encouraged the development of  electric railroad equipment, including but not limited to electric traction motor, pantograph, and overhead lines or 3rd rail exclusively designed for highspeed railroad; suspension system, body structure for lightweight high-speed trains, let alone the development of infrastructure that would have required for running a high-speed railroad system, and the change of traveling habit of American long before the WWII era, the country would have been benefited directly without a doubt. The CNYAL would also have been used to transport troops during the WWII, at least 50% (or more) travel time saved between NYC to Chicago if the top speed of the trains on the CNYAL was improved and shortened throughout the early 1900s to the 1940s.  The CNYAL would have been powered by steam indirectly by steam-electric power stations, but of course, my fantasy HSR for America would have been running by steam-streamliner, like the Pennsy duplexes and UP's steam turbine. 

Some extensions of the CNYAL would be interesting: Chicago to Denver via St. Louis and Kansas City, Toronto to Chicago via Detroit (That would have made it an international high-speed rail and Miningman could use it). New York to Denver in 18 hours or less! Who wants to join? 

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Posted by Overmod on Thursday, January 16, 2020 10:00 AM

Jones1945
Overmod: If the Sam Rea Line was built, I hope that it wasn't PRR built it alone because, in the cruel reality (with 20/20 hindsight), PRR should have cooperated with other RRs like NYC and B&O to beat the odds.

The initial problem with this is that NYC (and to a lesser extent B&O with NYC connection) had utterly no need for a super railroad running from Harrisburg to north of Pittsburgh when far less heroic engineering could have improved significant parts of the Water Level Route (or the B&O/Reading/CNJ route to New York from the West) to comparable speed.  

Were there to be construction overruns, or difficulties, or ongoing maintenance problems or costs, any 'joint venture' might find highly leveraged expenses for (as you indicate) relatively small actual high-speed gain, and less 'monetization' potential.  Incremental removal of the (many!) small and large bottlenecks either on the PRR Chicago routes or the 'Northeast Corridor' south to Washington would have produced essentially the same time savings with dramatically less work and risk (and quicker actual RoI).

True high-speed construction would have involved some very different details from what a Sam Rea Line would have received in 1923.  A number of these, such as practical class 9 track structure, only evolved decades later, well after the LGV development got under way.  In particular I think fairly substantial 'active tilt' would be required many places on the Rea line (and its prospective contemporary extensions to either side) and designng, providing, and maintaining that even in the headiest Fleet of Modernism days would have been near-impossible and perhaps often dangerous.

I'd have been amused to see a completed Chicago New York Air Line Railway built out to double track with proper high-speed overhead power (probably catenary rather than improved pole) and the degree to which it would compete with heavy railroads throughout subsequent "likely history".  (My guess would be conversion to four-lane "Turnpike" at a fairly early date, following the example of the Pennsylvania Turnpike and possibly changing the course of the New York State Thruway as built.)  Unlike the South Penn, a CNYAL would have been inherently straight-graded and have few curves...

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Posted by Jones1945 on Thursday, January 16, 2020 9:33 AM

Peter: I guess this is the three-locomotive train you mentioned: https://www.ilportaledeitreni.it/2019/05/26/253697/

Overmod: If the Sam Rea Line was built, I hope that it wasn't PRR built it alone because, in the cruel reality (with 20/20 hindsight), PRR should have cooperated with other RRs like NYC and B&O to beat the odds. The Sam Rea Line would have been the first high-speed rail in America that allow express passenger trains went through some rather long tunnels at high speed, therefore, from simple things like stronger or more flexible window frame and glass that could withstand the pressure fluctuation to evacuation plans and facilities for emergency situations in the tunnels, a lot of things would have been thoroughly discussed. There is one essential fact that put me off the topic, which is the inevitable postwar decline. The Sam Rea Line was financially impractical; It could have decreased the travel time from NYC/Washington DC to Chi-town (and St. Louis?) by merely three hours only (probably more than three hours if diesel engine was used), let alone the route bypass two major cities, Pittsburgh and Philadelphia, I don't think the original Sam Rea Line would be competitive enough to attract the general public to give up their cars or travel by air in the late 1940s. 

I wish there was a HSR that based on the idea of Sam Rea Line could provide a 9-hour schedule for New York/Washington DC to Chicago (and St. Louis) express trains. Day trains (all-coach train just like the SP Coast Daylight) depart from 6 am to 12 pm, arrive in both directions from 3 pm to 9 pm or later, night trains (sleeper, slower, like The Lark of SP) depart from 6 pm to 10 pm, arrive at the destination next morning. But I still doubt that it would be competitive enough, even SP's Coast Daylight couldn't withstand the postwar decline... I guess a 4-hour schedule would do it, but not even the never-existed-156mph-S1 could do it...Surprise 

 

 

 

 

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Posted by Overmod on Tuesday, January 14, 2020 5:44 AM

M636C
I am reminded of a trip I made in early 1974 from Allesandria to Savona in Italy.

Of course the Europeans are famous for developing practical 'four-power' locomotives and systems of operation to run and maintain them correctly.  I believe to this day there are TGVs built to run on multiple power sources.

We have discussed the existing proposals for dual-mode at 'equivalent diesel horsepower' including the very detailed one for Conrail.  I do not think there is particular difficulty in adapting this to variable sections of from 11kv nominal at 25Hz to 25kV or even 50kV in places at 60Hz.  

I doubt the big tunnels on the Rea and other lines would have either modern-high-voltage catenary clearance or easy attainment of 'double stack' clearance.  That would involve possibly heroic modification scale and perhaps even preferential abandonment (a la A&S perhaps) in the bad old days...

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Posted by Overmod on Tuesday, January 14, 2020 5:29 AM

Where you make the high-speed engine change from electrification remains significant, especially with the prospect of the Water Level Route being able to run steam through (with the 64T tender on C1as, and of course with ordinary diesels).  That could be pushed relatively east with aggressive tunnel ventilation once you get past the severe ridges of the Alleghenies, but those kinds of fixed costs including the power to drive them may not bode well for profitability 'later'.  

Electrification poses its own little issues.  PRR had no earthly idea in 1923 how to build an effective high-speed electric locomotive, and really wouldn't figure it out well into the Thirties; I have the grim suspicion that pre-'27 heavy internal combustion would follow the same wacky chassis conventions even the larger locomotive companies were touting then.  It might have been fun to see what could be done to save a fleet of AC L5s, but it wouldn't be pretty, it wouldn't be cheap, and it wouldn't have a long life -- conversely the switch to 428A traction motors might have been reduced had larger numbers of 'GG1s' been needed right away.  To the extent electrification of a high-speed line west of Harrisburg had been provided (perhaps on the model of a passenger Big Liz) the evolution to "DD2" architecture inherent in the 1943 electrification plan might have been different or indeed as absent as it turned out to be in postwar design prioritization.  It might have been fun to see a postwar PRR take up the best of French high-speed practice in the Fifties, with emphasis on 11 or 12.5kV AC to monomoteur drive on a railroad built to over 120mph standard...

Which further brings up the fun of a post-PC, post-Amtrak operation, largely with 'legacy' equipment but looking at the options available to electrified freight in the '70s (GM6C, GM10B) or '80s (the GE proposal for improved E44s embodied in 'test article' 4483).

All the usual caveats about 'writing alternate history' apply here; many things well-established in modern practice might have remained 'roads not taken' while other approaches with less ultimate utility (or familiarity!) might have developed or needed to be revised otherwise.  It can be difficult to fix 'apostolic succession' in many things regarding evolution of the PRR in the respects we're talking about, and while there are certainly some clear wrong answers, there are few if any objectively right ones that could have been identified as such by logical people in authority at the time...

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Posted by Overmod on Tuesday, January 14, 2020 5:23 AM

Where you make the high-speed engine change from electrification remains significant, especially with the prospect of the Water Level Route being able to run steam through (with the 64T tender on C1as, and of course with ordinary diesels).  That could be pushed relatively east with aggressive tunnel ventilation once you get past the severe ridges of the Alleghenies, but those kinds of fixed costs including the power to drive them may not bode well for profitability 'later'.  

Electrification poses its own little issues.  PRR had no earthly idea in 1923 how to build an effective high-speed electric locomotive, and really wouldn't figure it out well into the Thirties; I have the grim suspicion that pre-'27 heavy internal combustion would follow the same wacky chassis conventions even the larger locomotive companies were touting then.  It might have been fun to see what could be done to save a fleet of AC L5s, but it wouldn't be pretty, it wouldn't be cheap, and it wouldn't have a long life -- conversely the switch to 428A traction motors might have been reduced had larger numbers of 'GG1s' been needed right away.  To the extent electrification of a high-speed line west of Harrisburg had been provided (perhaps on the model of a passenger Big Liz) the evolution to "DD2" architecture inherent in the 1943 electrification plan might have been different or indeed as absent as it turned out to be in postwar design prioritization.  It might have been fun to see a postwar PRR take up the best of French high-speed practice in the Fifties, with emphasis on 11 or 12.5kV AC to monomoteur drive on a railroad built to over 120mph standard...

Which further brings up the fun of a post-PC, post-Amtrak operation, largely with 'legacy' equipment but looking at the options available to electrified freight in the '70s (GM6C, GM10B) or '80s (the GE proposal for improved E44s embodied in 'test article' 4483).

 

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Posted by Overmod on Tuesday, January 14, 2020 4:36 AM

The EMD is no 'solution' to the exhaust concern, and the issue in the tunnels is much more with stalling than with 'making it through' (and it's the passengers that are the greater concern for the 'experience'.)

Might be a use for 'fireless storage' of heat in supercritical water, including better lagging.  

I have, in fact, looked at the idea of traction motors and control gear on tenders.  They need careful protection from waterscooping if that is to be done; lots of fun with stray current and conductive salts... but the possibilities of dynamic or regenerative braking.

Note that there is less 'dual service' use for the Rea Line improvements (just as there is no 'passenger' reason for the Atglen & Susquehanna) both because of the Pittsburgh 'bypassing' and the tunnels.  I believe the page that covers the Rea Line also discusses possible extension west (to Fort Wayne and the 'speedway) and improvements east of Lewistown in particular a 'bypass' of Philadelphia and all the hassle to get to the 'NEC line' perhaps north of Trenton.  These are important parts of one-speed grade and curve control.

There is a careful point to consider here.  Most of the actual trains will still be sleepers, which implies much of the running will be at night where 110mph operation may be disturbing unless great care is taken; there is also a minimum reduction of time beyond which 'heroic' speed is counterproductive.  To an extent the right track design will include proper geometry for comfort and smooth operation including at junctions and crossovers.  

Some of the 1923 construction priorities might be different by 1943 (when the electrification alternatives were being proposed) and different again by the early Fifties.  If we leave sleeping comfort out, the recognition during the early LGV planning (counterpart to TGV trains) that very steep peak grades can be worked by high-speed trains economically becomes a consideration.  

 It is difficult to propose much of this without as you note leaving out the diesel advantages, whether as touted pre-1927 (as to Clessie Cummins) or by the time of the Baldwin modular project.  The use of EMD power designed for tunnel use would be an interesting exercise... as would 'dual mode' either in its full or 'lite' sense with limited catenary in tunnels or remaining grades.  I do think that extension of Gibbs & Hill electrification to at least the passenger main line becomes a priority -- and that much of its cost would essentially be 'sunk' comparatively early in the postwar die off of passenger-train patronage, the question then becoming whether faster remains 'better enough' to preserve it.  Personally I think there would not; the experience with the 'Broadway bubble' after 1958 (or conversely with the B&O competition with the Liberty Limited, which conclusively won the war on speed and amenities but lost the peace only a couple of years later).  

Fast TOFC does have some better opportunity if bridged from the A&S via Enola and then the optimized Rea improvements.  Here some improved gateway alignments other than Chicago begin to be interesting, and some of the high-speed potential outside passenger comfort might be of practical use.  However this would involve 'monetizable' use of the quick service -- for example counterpart service to ATSF 'Super C' levels -- and it has not been demonstrated fully to me that this model has worked for most freight and even most M&E historically, well enough to justify the full sunk cost of improvements and maintenance to assure it.

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Posted by M636C on Tuesday, January 14, 2020 3:31 AM

I am reminded of a trip I made in early 1974 from Allesandria to Savona in Italy.

The train had three locomotives, an E626 3kV DC Bo-Bo-Bo, an E554 3ph AC E (0-10-0) and an E432 3 ph AC 1-D-1 (2-8-2).

The train departed Alessandria with the E626 working to the first station, which was still electrified on AC. the E626 coasted in with its pantographs down. The E554 and the E432 raised theirs, The E554 shunted the E626 out of the way and the train proceeded behind the E432 at a constant 35 mph (or so).

There were DC railcars that had rectifier trailers with twin pantographs for AC that ran through.

Peter

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Posted by Jones1945 on Tuesday, January 14, 2020 12:59 AM

Overmod

But you see, anywhere you have an improved New Main Line you also have mechanical turbines that blow any reciprocating locomotive out of the water.  Electrification was understood to be needed for the longer tunnels, but the case for it in Ohio would not have to be made with V1s available... let alone versions with Bowes drived 

Some random daydreaming *crazy thoughts roaming in my head, sharing them here just for *fun:

There were 22 tunnels on the proposed SRL, the longest one would be 5.57 miles. If every express train needed to stop in front of the 22 tunnels and wait for the electric engine to pull them through the tunnel, a few hours of time would be wasted. (Even though some tunnels would be very close)

Changing power without stopping: For those longer tunnels that were not suitable for Steam engine operation, only the tunnel sections were electrified. The S1's tender (There would have been a fleet of them, maybe #6100-#6109) followed by an electric engine, probably a PRR Class AA2 B-B 2000hp unit or 3000 hp B-B-B-B unit, "disguised" as an extra tender for better appearance (optional). The electric unit could be controlled from the Cab on the S1, T1, S2, S3 and all steam engines assigned to use the SRL. 500 meters before entering the Tunnel, train crew shut off the throttle and slide the train into the tunnel, once the electric unit connected to the electric network, train crew control the electric unit and pushing it to the limit to maintain the trains speed in the tunnel as much as it can. Once the train left the tunnel, let the steam engine pick up the speed again and make up the time, that was one of the best things a PRR Duplex could do. 

For shorter tunnels, just give extra attention to the ventilation system, improved Cab design and provide oxygen mask and tank for the crews!

The electric unit didn't have to follow the train for the whole journey. They could be attached to the train from major stops like Fort Wayne or any stop along the SRL, when they were not needed. No need to build completely new electric engines, rebuilt and convert the older one. Larger and more powerful until for longer and more important trains, smaller units for short consist...

 

Too complex and impractical? The most straightforward solution:

Call EMD for a deal! 1000 miles in 10 hours, no engine change!Whistling

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Posted by Overmod on Monday, January 13, 2020 10:23 PM

But you see, anywhere you have an improved New Main Line you also have mechanical turbines that blow any reciprocating locomotive out of the water.  Electrification was understood to be needed for the longer tunnels, but the case for it in Ohio would not have to be made with V1s available... let alone versions with Bowes drives.

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Posted by Jones1945 on Monday, January 13, 2020 10:01 PM

Overmod

Personally I think that the S1 was a very reasonable 'take' on a huge passenger locomotive ... the problem was that PRR wasn't a huge-passenger-locomotive railroad at the time, and didn't really have the money to become one.  It's really a late-Twenties design meant for late-Twenties New Era railroad rebuilding.

I think it's to PRR's credit that they went straight from the E8 Atlantic (perhaps recognizing they weren't going to have many places to run Hiawatha-size trains!) to putting two under a big common boiler.  Fits right in with their high-speed policy at that time (and one big reason they supported an unconjugated duplex).  All they needed was an effective autonomic antislip device, and they were about 95% there with the one on the Q2s ... just that they didn't make it servoproportional.

Rebuild it with mid-Forties tech and ... you'd really have something.  Problem was it was too much 'something' for PRR, a kind of ballet-dancing 6'8" Jayne Russell that never got the right kind of dates because everyone who might have the touch was scared of her, and at times for sensible reasons. 

I still believe that S1 was the right, and was probably the best passenger locomotive to serve on the proposed Samuel Rea Line, even though she was built as a show car for the 1939 World Fair. From Rochester, PA to Lewistown, PA, there are another 180 miles of "straight" track or new race track on the Samuel Rea Line for her to spread her wings. So, from Fort Wayne to Lewistown, the length of the PRR race track would have been increased to 450-480 miles. Assuming the S1 could sustain 110mph for the whole 460 miles journey nonstop, it would have been taken her 6-7 hours to reach Harrisburg from Chicago! A few more hours later, the train would reach New York or Washington with the help of GG1. For passengers to and from Pittsburgh, sections or shuttle streamliner service could have been arranged between Pittsburgh and a new station on the Samuel Rea Line. Shuttle trains could be powered by upgraded + streamlined K4s or even E6 4-4-2!

If Samuel Rea Line was electrified, I wish there would have been something even more exciting than the S1. If not, let's save the money and keep using coal-burning locomotives on the Sam Rea Line. T1 or even the original Q1 could have been playing a similar role as the S1, but there was at least one thing about S1 that not even the N&W Class J couldn't beat: the riding quality in the cab! Not many steam engines could provide Pullman-level-comfort at a very high speed.

(Click to enlarge)

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Posted by Overmod on Monday, January 13, 2020 7:36 PM

Personally I think that the S1 was a very reasonable 'take' on a huge passenger locomotive ... the problem was that PRR wasn't a huge-passenger-locomotive railroad at the time, and didn't really have the money to become one.  It's really a late-Twenties design meant for late-Twenties New Era railroad rebuilding.

I think it's to PRR's credit that they went straight from the E8 Atlantic (perhaps recognizing they weren't going to have many places to run Hiawatha-size trains!) to putting two under a big common boiler.  Fits right in with their high-speed policy at that time (and one big reason they supported an unconjugated duplex).  All they needed was an effective autonomic antislip device, and they were about 95% there with the one on the Q2s ... just that they didn't make it servoproportional.

Rebuild it with mid-Forties tech and ... you'd really have something.  Problem was it was too much 'something' for PRR, a kind of ballet-dancing 6'8" Jayne Russell that never got the right kind of dates because everyone who might have the touch was scared of her, and at times for sensible reasons.

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Posted by Jones1945 on Monday, January 13, 2020 5:58 PM

Overmod
I'm pretty sure that was a wise decision based on 'what they knew then'; I'm equally sure that they sure figured out it was unnecessary by only a couple of years later (with the 'production' version of the passenger duplex).  I'm also tempted to say that an over-the-top passenger locomotive needs over-the-top driver diameter to assure world's-fair quality 'over-the-top speed' if you can stand the pun...

Fair enough! At least PRR didn't pick a vintage 86" or higher to create even more talking points for the "show car of the decade", let alone 86" wasn't high enough to beat the 90.55" driver on the DRG Class 61 of German. The S1 was officially aimed to top 100mph "only", folks from the UK might have found this figure unimpressive, even though their A4 Pacific and Coronation Class usually operated at 90mph for their 300-short-ton-express. 

I have been reviewing the PRR Chronology line by line in spare time, you are right that the S1 actually cost much more than $660,000. I will post the updated figure after data consolidation.

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Posted by Overmod on Saturday, January 11, 2020 11:36 AM

Jones1945
If MILW and C&NW rebuilt their [F]-7s and E-4s with 80" driver (or smaller), everything besides the size of the driver and all necessary alteration related to the change of driver size remained unchanged (including boiler pressure and size of cylinder), would their top speed have been significantly increased?

Probably not.  I, personally, think that any design that is essentially hampered by poor steam mass flow is likely to be more hampered by the higher cyclic rpm than aided by the gain in tractive effort at top speed.  There is a bunch of other stuff that would have to be modified to make this diameter change, as these are high-speed passenger engines where riding and guiding characteristics are critical.

Starting and low-speed work might have been another matter entirely, but I doubt that was a principal concern in the design of either class, as I think the choice of 78" for the Burlington S-4 clearly was. 

The recognition that 84" drivers (or higher!) were not essential for high effective speed really didn't come until 'after the R-1s' -- up until then the wisdom that 84" drivers on nothing more than six-coupled was essential to running over 90mph was probably still well established.

Far more important would be good 'internal streamlining' in the Chapelon senses, perhaps involving larger and longer-travel valves to give prompt opening and unshrouding with high steam flow.  Rigorous attention to detail design in the balancing would be a secondary concern, I think specifically including Timken rods and bearings.

Was Lima the only one major American steam locomotive manufacturer that never constructed any steam locomotive with driver larger than 80" during the "Superpower" era?

They certainly never needed larger drivers for anything they got a contract to build.  However, all you have to do is look up the patents for Woodard's proposed express locomotives to know this was no 'choice' in the age before lightweight rods and full balancing.  Whether or not Alco paved the way for effective high speed, or AMC derived a formula for effective speed in freight power, in the postwar period Lima chose to go with more capable boiler construction (e.g. Double Belpaire) with more economical and precise valve gear (Franklin type "C" rotary-cam poppets) and certainly accepted the logic of relatively long stroke and small lighter pistons/rods/crosshead and nominally smaller drivers.  

(Lima involved the design of PRR S1 but it was PRR insisted to use 84" driver on S1 after they inspected the newly built C&NW E-4)

I'm pretty sure that was a wise decision based on 'what they knew then'; I'm equally sure that they sure figured out it was unnecessary by only a couple of years later (with the 'production' version of the passenger duplex).  I'm also tempted to say that an over-the-top passenger locomotive needs over-the-top driver diameter to assure world's-fair quality 'over-the-top speed' if you can stand the pun...

Did New York Central ever consider [using] larger drivers on their Hudson to build a "84"-drivered short-stroke conventional-wisdom speedster"?

Not anywhere I have been able to find -- and that specifically includes any services like the Mercury that 'might have' been established with the equivalent of a Milwaukee A and dedicated five-car trainsets to get dramatic high speed with high-profile operation.  

Most notably Kiefer went with many of the cardinal principles of the PRR T1 in his 'perfected' duplex, most notably the retention of 79" drivers and the same short stroke (determined by pin to axle seat dimensions in the driver centers).  There was little question that this would have gone every bit as fast as NYC track and cars would permit, and done it efficiently enough to require no fuel stops between Harmon and Chicago (worth more than a few mph in potential top-speed capability right there!)  I think that any possibility of the 'follow-on' to the (rather large) order of J-3as would have been late enough to establish lower-wheel duplexes with big 'common' boiler architecture as the real high-speed choice (up to any speed it would be safe to run reciprocating steam for 'the public' in the first place).

Was the skittish-racehorse performance of NYC 999 inspired them to not blindly follow that conventional wisdom at the time?

You'll recall that much of the 'point' of the 86"-drivered version (for extreme high speed) was undone a comparatively short time afterward, and more pointedly none of the vaunted 20-hour and then 18-hour trains had anything more high-wheeled than 'normal'.

PRR did have an 'express' locomotive with 84" drivers, but it was a cross-compound, and the large diameter was (as with Golsdorf) used to keep machinery speed minimized.  

The boutique traffic to Atlantic City in the last decade of the 19th Century certainly resulted in some high-wheeled and successful power (even higher than 84"!) but you'll notice that subsequent high speed on that part of the Reading went back to nominally smaller drivers. 

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Posted by Jones1945 on Saturday, January 11, 2020 8:42 AM

Overmod
One of the great catastrophes of steam design happens right at the cusp of this: the ACL R-1s as initially balanced.  Wrong understanding, wrong formula ... revealed "I told you so" wisdom producing amazing levels of track wrecking from a locomotive that should have been one of the best.  While the conventional practice puts together the C&NW E-4, which couldn't even get its test train over 100mph, or the ATSF 3460 class, which fell off the porch between 102 and 106mph or so as its inadequate valves and passages ran out of ... well, steam.  And the ominous lack of true high-speed test data for the Milwaukee F-7s, suspiciously similar to E-4s in many significant dimensions, which would run all day at 100mph but ... perhaps ... not that much higher.

Compelling! If MILW and C&NW rebuilt their E-7s and E-4s with 80" driver (or smaller), everything besides the size of the driver and all necessary alteration related to the change of driver size remained unchanged (including boiler pressure and size of cylinder), would their top speed have been significantly increased? Was Lima the only one major American steam locomotive manufacturer that never constructed any steam locomotive with driver larger than 80" during the "Superpower" era? (Lima involved the design of PRR S1 but it was PRR insisted to use 84" driver on S1 after they inspected the newly built C&NW E-4), I am not implying Lima knew something Baldwin and Alco didn't know at the time though, they probably put their focus on successful products like their 2-8-2 and 2-8-4.

More questions roaming in my head; did New York Central ever considered to use larger drivers on their Hudson to build a "84"- drivered short-stroke conventional-wisdom speedster"? Was the skittish-racehorse performance of NYC 999 inspired them to not blindly follow that conventional wisdom at the time? 

Speaking of the handsome ACL's R-1, there is a photo showing the damage of the rail track on this page: http://www.trainweb.org/aclr1/ 

"Photo of Damaged Rails from Ralph P. Johnson's book "The Steam Locomotive"

 

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Posted by Overmod on Friday, January 10, 2020 12:08 PM

A little bit more of my 'take' on the CNJ (and the Central of Pennsylvania): this railroad was the brief and spectacular jewel of Archie McLeod's Reading Combine.  See the building-for-the-ages improvements in the Allentown-Bethlehem-Easton area, particularly some of the bridges.  Consider the use of the CNJ as the effective northern terminal extension of the B&O to New York, connecting via the rapidly-improving Reading main in the process.  

Had the wheels not come off the Combine so definitively (and off the rest of the US economy shortly thereafter) I think we'd have seen a very different CNJ, one with a physical plant not second to Cassatt's, one with a Narrows tunnel off Staten Island to Bay Ridge even in the absence of Lindenthal's joint bridge...

For those who don't know the sequence of events concerning the Poughkeepsie Bridge completion and the wheeling-and-dealing in the short time between its completion and the economic collapse, Chris Baer has a pretty good timeline on the Web; start here with this PDF timeline and work forward and backward as necessary.  There is a PDF article here that describes the shenanigans in this short period in reasonably coherent detail.

It will pay those with patience, I think, to look over at what was still a relatively well-guided railroad strategy at Morgan's, as it's easy to get the impression that Morgan intentionally wrecked McLeod for little more than 'getting too big for his britches' with little regard for the ensuing consequences.  

It does have to be said, though, that a non-overextended B&O with a Royal Blue Line speedway from Baltimore north to New York (and easy side trip across the harbor for freight, and only slightly more indirect service to Manhattan ... much less indirect, I might add, than the NYW&B thought it needed) would have been an interesting thing to contemplate.  Particularly if subsequent motive-power development up to the Forties had been allowed to progress with ample capitalization...

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Posted by Overmod on Friday, January 10, 2020 11:50 AM

CSSHEGEWISCH
I'm not sure that anything could have saved Jersey Central, a glorified terminal road with no long hauls.

Compounded by its heavy reliance on anthracite traffic and service of dying regions of the country...

Interestingly enough, the Baldwins lasted long enough to be photographed ... running ... in Scranton in 1965 (as I recall, in an A-B-A set but different paint).

I don't think even Enron-level accounting creativity could have saved Penn Central from itself -- the operating side alone would have imploded down into disaster, I suspect with about the same ultimate timetable.  (And in my opinion, that's with or without the New Haven being shoehorned in at the last minute to ensure nonprofitability without extensive reworking of operations priorities.)

I am of the opinion that the spectacular nature of the Penn Central debacle, whether or not it was financially accelerated, was something of a very good thing: I doubt we'd have had Staggers or USRA/Conrail without it, and had things taken even a few more years to degrade, the situation might have ended with more abandonments and functional failures, perhaps dramatically more.

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Posted by CSSHEGEWISCH on Friday, January 10, 2020 10:24 AM

I'm not sure that anything could have saved Jersey Central, a glorified terminal road with no long hauls.

David Bevan and creative accounting had more to do with the collapse of Penn Central than Stuart Saunders' incompetence.

The daily commute is part of everyday life but I get two rides a day out of it. Paul
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Posted by Flintlock76 on Friday, January 10, 2020 10:12 AM

Yeah baby, diesels sure didn't save my Jersey Central, even those Baldwin "Babyfaces" that could pull anything out of the yard including the yard office, and they sure didn't save the mighty New York Central, hey, even Al Perlman couldn't save it!  

Stuart Saunders sure could kill it though, and the Pennsy too for that matter.  Fat lot of good diesels did him!   Wink

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Posted by Miningman on Friday, January 10, 2020 1:54 AM

Yeah, that's a good way to end it, on the possibilities. I've often just shrugged at the C1a concept, another beautifully designed piece of engineering pointing to the future but scrapped in 3 years time over a mad rush to buy some crappola, expensive, poorly designed latest and greatest from one manufacturer only to find out you have to buy an even more expensive one from another to keep your mainlines moving. 

Gimme those money saving Diesels.. fast. 

What could go wrong? 

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Posted by Overmod on Thursday, January 9, 2020 4:57 PM

Jones1945
Yes, the PRR S2 had 68" drivers, even smaller than N&W J's driver by one inch ...

Two inches.  Very important inches for a number of classes of power...

but still capable to pull a 17-car train over a distance of 30 miles (level track) at a speed of 110 mph, so a properly-balanced 72" driver on M1a/b variant should have been adequate for express passenger train.

The problem is that these are not comparable.

The S2 is manifestly not a reciprocating locomotive.  There is a certain amount of 'statutory imbalance' in the quartered connecting rods, but they can be balanced rotating, so the only real augment-inducing couple that 'matters' is the difference laterally between where the center of mass of the counterweight in each driver is a bit 'inside' the center of mass of the net rod mass for that driver.  So there is a bit of induced hammer-blow, but it is rather obviously a tiny fraction of adhesive weight up to substantial rotational speed; far more speed,likely, than the corresponding much higher (fixed by the reduction-gear train ratio) speed where windage, exhaust clearance and other losses begin to seriously beset the steam turbine doing the rotational drive.

The situation with the 72" M1b driver is quite different; it has all the augment forces described in Johnson's book.  For example you have the reciprocating mass of the mains to deal with, plus the rotating component of the mains carried proportionally far outboard, so the balancing is more complex; there is also the small vector component of the piston thrust in the vertical plane (which is the thing Voyce Glaze left the 80lb of reciprocating balance in the main driver to deal with) -- for 'maximum speed potential' you calculate this for open throttle at about 40% cutoff, which would correspond to peak achievable balancing speed.  

We assume well-adjusted Franklin wedges with appropriate spring pressure, so there is no slack in the longitudinal 'fit' of the axleboxes/lateral-motion devices in the pedestals.  We further assume a good spring pressure on the Franklin radial buffer between engine and tender ... which raises the spectre of surge at high piston thrust or resonant conditions.  This is what the Langer balancer is designed to counteract, and geometrically it ought to do so very well; this leaves nosing and hunting to be compensated as Voyce Glaze intended, with stiffer lateral and better lateral damping, including better lateral-motion control of the lead driver pair in curves.

But not only PRR's S1:  MILW, CNW's, and ATSF's 3460 Class Hudson also had 84" drivers, I wonder why Alco, Baldwin, and RRs had blind faith on driver larger than 80" for their express passenger steam engine? 

It was not blind faith, it was conventional wisdom.  That it was erroneous wisdom, and relatively quickly overcome by events, does not detract from its validity as a topic for discussion.

As far back as the Monster of 1836, the idea was that a good honkin' tall driver diameter would translate into high speed.  In fact the spokes on Monster's drivers were paneled in to avoid strewing levitated ballast at lethal velocities ... something I do think would have been observed.  You have Cramptons.  You have geared-drive engines of various kinds that spin drivers faster 'by other means'.  You have all the 'singles' that constitute the early age of 'duplexing' with single axles in an age when side-rod clearances and bearing technology meant 'coupled wheels would be slower'.

And yet, even then it was clearly recognized that high speed came from boiler steam-generation capacity, not from high drivers.  Each inch over about 78" results in a severe toll in 'default' tractive effort, with the 86" on NYC 999 clearly putting the engine over the line into skittish-racehorse performance.  And the presence of side rods capable of sharing Super-Power levels of piston thrust pretty well meant relegation to slow speeds, or the use of three-cylinder drive to keep the thrusts down and augment better distributed... and so we come to Eksergian, in 1928, carefully analyzing the different components of balance.

Now, in the early Thirties it was 'common knowledge' that the only true high-speed power was going to be at most six-coupled.  In the absence of a careful analysis of balance the 'solution' for 100mph had to be 84" drivers (ideally with the main in line on the lead driver pair, and four-coupled to keep mass and bending stress in the rodwork bearable) and ... in some cases ... it was a reasonable prescription.

One of the great catastrophes of steam design happens right at the cusp of this: the ACL R-1s as initially balanced.  Wrong understanding, wrong formula ... revealed "I told you so" wisdom producing amazing levels of track wrecking from a locomotive that should have been one of the best.  While the conventional practice puts together the C&NW E-4, which couldn't even get its test train over 100mph, or the ATSF 3460 class, which fell off the porch between 102 and 106mph or so as its inadequate valves and passages ran out of ... well, steam.  And the ominous lack of true high-speed test data for the Milwaukee F-7s, suspiciously similar to E-4s in many significant dimensions, which would run all day at 100mph but ... perhaps ... not that much higher.

ATSF now turns to rebuilding the sow's-ear 3751 class to larger drivers, better valves and passages, suspension and bypass valves ... and lo! winds up with a high-horsepower locomotive that is just as fast, in fact faster, than the 84"-drivered short-stroke conventional-wisdom speedster.  They take a leaf from this to build 2-10-4s with relatively high drivers (the 'sweet spot' for freight or most dual-service being somewhere in the 74" to 76" range) with a longer rigid wheelbase than a PRR Q2 duplex ... and we get into the world in which the C&NW works over its H-class 4-8-4s not once, but twice, probably winding up with an engine the effective equal in speed of the E-4 but dramatically more useful in just about every context where the track could handle the additional weight and forces of a locomotive that size.

What happens at the end of the Thirties is that across a wide range of designs, it becomes clear that large-firebox eight-coupled power is capable of going just as fast as a given railroad will permit.  In the case of the PRR, that meant that an 80"-drivered duplex would not only reach the speeds expected of the heavy improvements in the Sam Rea Line and other 'new main line' improvements, but the highest speeds safe to reach with reciprocating power of any practical driver diameter.  The only reason to go to 84" drivers would be to preserve the (driver-center structurally limited) 26" short stroke on a T1 'follow-on' (likely not a derivative of the E8 Atlantic design, but something like an improved S1 with all four sets of rods common and very little if any formal overbalance) and by then it was increasingly recognized that 26" was ridiculously short for what modern balancing could give you...

By the time of the 'late' AMC Berks, the NYC L-4 (and prospective later power) and the PRR re-tiring of some of the J1as, we see the interesting formula of drivers somewhere in the low 70s 'new', comparatively long stroke (suicidally long by even late-Thirties standards; sometimes 34") but smaller bore to lower reciprocating mass and peak piston thrust, and lightweight rods ... with or without roller bearings and dramatic thin section/deep web.  (Note carefully the main-bearing design on the UP 800 rods, which accomplished many of the real-world ends of rod rollers without either the first cost or the careful twitchiness necessary in maintenance.)

It is difficult to imagine 'cost-effective' M&E on PRR, even with some form of palletization or containerization that would work with such trains, involving even peak speed above 90mph; on the other hand, the ability to accelerate quickly after checks and over difficult profiles without corresponding expense of fuel and water is nearly as quickly and easily recognized as it was in the France of the artificial socialist speed limit.  Which leaves two things: the future of nonreciprocating steam power, which is succinctly the story of the S2 and V1 with proper drive technology, and the use of high-horsepower locomotives with limited water rate.  On the latter would founder all the advanced design of the Forties: the contest was still there, barely, in 1946, but even by the time Kiefer's report was issued the game was visibly over.  For steam to 'look good' you needed the appropriate traffic -- long distances, very high speed, guaranteed profit margins, very quick turnaround, well-organized maintenance from guys in asbestos suits willing to use them.  Remove almost any of those factors -- and in the late Forties all of them were disappearing at an accelerating rate -- and the opportunity costs of dieselization look as compelling as history bore out.

Which is where a sensible-dimensioned locomotive capable of extraordinary performance beats the tar out of a high-wheeled prima donna.  Even a Niagara could be operated fast, strong, or almost inconceivably cheaply depending only on the service expected of it.  A Kiefer-corrected C1a would still have had some of the limiting faults of obligate high-speed design, most particularly the 26" preserved stroke (which was almost certainly a necessary part of the design in giving true run-through on 64T) and ... knowing what we know about Dieseliners ... would likely have suffered the fate of the poppet-valve Niagara and the PRR T1 as a first-line express locomotive.  On the other hand, any driver greater than 69" that would fit under an A-2a shell would have been interesting in a great many ways...

... were even a couple more years given to modern Eastern steam.

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Posted by Jones1945 on Thursday, January 9, 2020 1:09 PM

Overmod
The 84" drivers would be a colossal mistake on PRR, and would have been more so than on other roads with more 'necessity' for them.  There is no need for greater than 80" on a working PRR express locomotive; in fact, I consider there to have been adequate evidence that a properly-balanced 72" M1a variant would have been a far better thing for PRR to 'modernize' than any Pacific... for what PRR needed its locomotives to do most of the time.  

Thanks a lot for the thorough explanation, Overmod! Yes, the PRR S2 had 68" drivers, even smaller than N&W Js driver by one inch, but still capable to pull a 17-car train over a distance of 30 miles (level track) at a speed of 110 mph, so a properly-balanced 72" driver on M1a/b variant should have been adequate for express passenger train. But not only PRR's S1, MILW, CNW's, and ATSF's 3460 Class Hudson also had 84" drivers, I wonder why Alco, Baldwin, and RRs had blind faith on driver larger than 80" for their express passenger steam engine? 

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Posted by Overmod on Thursday, January 9, 2020 5:40 AM

Jones1945
... I am still looking for a trustworthy source about the mechanical stokers on the Loewy K4s #3768. I have seen some brass train models, some in HO scale some O gauge, having a dual mechanical stokers on the #3768, I mean stoker like this ...

I cannot get that link to display, but you're describing a Duplex stoker, which is not an uncommon design.  See this thread for some associated discussion.

http://cs.trains.com/trn/f/740/p/249407/2783285.aspx

This is not a 'dual' stoker so much as it is a dual-elevator stoker.  In most stoker designs there is one 'table' to which the coal is delivered, centered under the firedoor, and you can see the jet (or scoop or whatever) action by looking in through the door or peepholes.  The Duplex left the firedoor area clear, bringing coal up 'around' it to either side, which theoretically would allow a higher mass delivery of coal from the worm up to the table(s).  This would not have increased the capacity of a K4 any more than even the most primitive of the early stokers designed for it (see the detailed information and drawings of Street stokers available on line) as the grate limit was comparatively low on even the most modernized of those locomotives.

In hindsight, If PRR chose another path; upgraded the K4s, K5 like how C&O rebuilt their F-19 Pacific (in 1947), instead of design and built the T1, they would have saved a lot of resources.

But you'd still have a locomotive needing to be doubleheaded on any substantial PRR consist ... except now, improved with a bunch of expensive components to be even more overkill than before.

Imagine a K4s like #5399, not only had poppet valve gear and front-end throttle equipped but also with roller bearings on all axles, Baldwin disc drivers, light-alloy rods, all-weather cab... or simply built a K6 instead of T1; larger firebox, higher boiler pressure, 84" drivers... That would have been looked like a B&O Class V Hudson without the watertube firebox...

... or, perhaps a little more pointedly, like an E8 Atlantic stretched by one axle, exactly the sort of thing I expect the PRR did with the E6 and K4 back in 1914.

The 84" drivers would be a colossal mistake on PRR, and would have been more so than on other roads with more 'necessity' for them.  There is no need for greater than 80" on a working PRR express locomotive; in fact, I consider there to have been adequate evidence that a properly-balanced 72" M1a variant would have been a far better thing for PRR to 'modernize' than any Pacific... for what PRR needed its locomotives to do most of the time.  

Why in fact no 'M1b' was ever built with the front-end throttle and sine-wave superheater elements, etc. is a mystery, although I suspect much of it is just as much 20/20 hindsight as the ability to discriminate gains from the Franklin System from gains due to better superheat or steam-generation effectiveness.  An M1 with disc drivers and alloy rods, a good cast bed, full high pressure, capable passenger superheater, and a front-end throttle would have been every bit as fast -- practically speaking -- as anyone's 4-8-2, and with the relatively slight enhancement of N&W-style balancing woiuld give you 'enough' of a higher wheel to get rid of the machinery-speed concerns expressed over the class J wheel size as tested. 

 

Overmod
 If they attempted high-speed suspension modifications for better riding or lower augment, I do not see any evidence of widespread adoption.
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Posted by Jones1945 on Wednesday, January 8, 2020 9:59 PM

Speaking of PRR K4s' upgrades and stokers, I am still looking for a trustworthy source about the mechanical stokers on the Loewy K4s #3768. I have seen some brass train models, some in HO scale some O gauge, having a dual mechanical stokers on the #3768, I mean stoker like this: 

I wonder if other Streamlined K4s had the same treatment. Not even a gigantic show car like the PRR S1 nor the much more powerful T1 had dual stoker like this. 

In hindsight, If PRR chose another path; upgraded the K4s, K5 like how C&O rebuilt there F-19 Pacific (in 1947), instead of design and built the T1, they would have saved a lot of resources. Imagine a K4s like #5399, not only had poppet valve gear and front-end throttle equipped but also with roller bearings on all axles, Baldwin disc drivers, light-alloy rods, all-weather cab... or simply built a K6 instead of T1; larger firebox, higher boiler pressure, 84" drivers... That would have been looked like a B&O Class V Husdon without the watertube firebox...

Overmod
 If they attempted high-speed suspension modifications for better riding or lower augment, I do not see any evidence of widespread adoption.

Would you mind explaining the difference between high-speed suspension and the lower-speed one on reciprocating steam locomotive? Do you mean using the high-speed pilot truck used on T1 and MILW's F-6 Hudson? Smile

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Posted by Overmod on Wednesday, January 8, 2020 9:16 AM

daveklepper
Regarding PRR  team-power acumen, look at the K4s in the Winter '19 issue,  pages 58 (1954) and 60(1941).  Count the differences, the modifications!

The chief problem I have with this hypothesis is that I don't think PRR ever really tried to 'implement real silk' fleetwide with what was increasingly a 205psi sow's-ear by comparison with everybody else's modern power.  You see them trying just about every version of disc driver (including Web-Spoke); they try lightweight rods and angle balancing; I think they even try engine beds.  They even get a taste of what a good sine-wave superheater and proper front-end throttle arrangements can do ... in the Lima-modified poppet-valve demonstrations ... and then attribute the gains to the valves and make no further attempt at either higher pressure or better superheat.  If they attempted high-speed suspension modifications for better riding or lower augment, I do not see any evidence of widespread adoption.

Government made them put those stokers on K4s, and as I recall PRR fought them tooth and nail over it.  It is hard to say that 'forcing' a K4 beyond what a good fireman could hand-bomb is necessary; long before that point PRR would just doublehead two together for the ultimate articulated passenger locomotive at suitable firing rate...  

The much better argument on stoker necessity involves the K5, which couldn't even remotely reach its potential without one, and the absence of stoker firing in that design makes the comparison between PRR's people and Kiefer even starker.

None of this meant to indicate that the K4, especially with slightly larger piston valves, wasn't a spectacular engine, dramatically ahead of its time (as was the E6) and remaining relevant as a high-speed locomotive all the way into the Fifties.  Just that there were very, very many ways they could have been improved over the years, some proceeding to the point of actual construction and experiment, but never quite applied coherently.

Admittedly, the [visible] ones do not make much difference in performance, just maintenance and ability to operate through snow.

Might make sense to list the important mechanical differences, as I suspect I still have something to learn about this era of K4 service.  If some of the mods were associated with decreasing coal quality (after the era from about 1948 to 1950 of emphasizing higher-quality washed fuel), that would be highly interesting.

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Posted by daveklepper on Tuesday, January 7, 2020 10:19 PM

Regarding PRR  team-power acumen, look at the K4s in the Winter '19 issue,  pages 58 (1954) and 60(1941).  Count the differences, the modifications!  Admittadly, the visual ones do not make much difference in performance, just maintenance and ability to operate through snow.  My memory tells me that I was informed that the K4s' real capability on the road was only realized after mechanical stokers were installed.

 

9,

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Posted by Jones1945 on Sunday, December 15, 2019 4:28 PM

Thanks Dave for your support and Overmod for another thorough reply! A lot of questions came to my mind, I am gonna share with you guys when I feeling better (no big deal, just caught a cold, hopefully not flu!)

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Posted by Overmod on Sunday, December 15, 2019 12:35 PM

Meanwhile, we have to ignore the parallel development line on mechanical turbines in order to do this hypothetical 4-8-4 thing -- there clearly being at least some interest in pursuing the design of the S2 for freight and M&E along the same lines as the S1 becoming the T1 design.  I have little real hesitation in saying that a debugged direct turbine with either Ljungstrom configuration and a reversing gear rather than dedicated turbine or a Bowes drive would have been a better answer than any reciprocating engine for the presumptive purposes PRR would have had for a 4-8-4.

There are alternatives, of course, for reciprocating engines, perhaps the most interesting of which would be a 'new' 4-8-4 design circa the state of the art in the era of the '47 Cyclopedia.  This might be approximated, to start, by looking at something like a WM Potomac and putting RC poppet-valve gear on it.  But you could get to it another way, which is to tinker slightly with a Q2 to produce a 69"-drivered eight-coupled sharing as many components as possible with 'regular' Q2s.  This would be an obvious candidate for refitting with lightweight rods, and it might be a highly interesting thing to compare with the N&W J design.  I'd expect to see a Langer balancer tested to reduce the surge component of any overbalance; I'd like to think the PRR motive-power people recognized the value of keeping overbalance in the main to a minimum.

Still a step backward both in dynamic augment and in power per unit from a Q2, so you'd have to look to shopping and maintenance concerns, especially those that 'double' on a four-cylinder simple engine, for a good reason to go with such a 4-8-4.

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Posted by Overmod on Sunday, December 15, 2019 12:21 PM

Jones1945
Pennsy probably would have tried, and compared the performance of a "Steam-powered R1" with a T1. It would have been a battle between Lima and Baldwin, just like what happened on the R1 and GG1 (BLW/Westinghouse Vs. GE/PRR)...

This is a highly interesting thing, but the parallel really goes the other way: the R1 was the tested 'invented here' alternative rather than the imported GG1 approach, and its design philosophy was not particularly apt.  

It's interesting to consider a 'simple T1' as a test article, but perhaps notable that if such a thing were ever considered there is no record of it, and no mention in any correspondence I have seen (or anyone else appears to have seen).  1940 was still the era ATSF was feeling out how high-speed large 4-8-4s would be built; it was by no means clear that augment could be reduced to the degree PRR would need for the engines to operate at "perceived T1 speed" and therefore comparatively little likelihood that the prospective very real improvements in expensive track maintenance for high-speed operation -- representing far, far more over time than the savings in tech on a nonduplex locomotive -- could be realized.  By the time of the N&W J testing, PRR had clear evidence of the value of lightweight rods on an eight-coupled locomotive; if they understood this, it appears to have been thrown out along with the too-low-wheel-for-express-locomotive opinion rather than embraced for M1 follow-ons.  Which is really the great road not taken in this era -- a M1a refitted with disc or Web-Spoke drivers and given lightweight rods might have been a highly interesting testbed.  One might even argue that across much of the PRR system, a boiler-improved M (say, with Snyder preheaters, better circulation, and more reliable feedwater-heat arrangements) would have done as much of the business as PRR needed or could actually use, comparable to how NYC found the latest Mohawks suitable.  (We might remember that the Niagara success was largely predicated on its ability to produce high sustained passenger speed with axle-driven air-conditioned consists with fast turnaround and guaranteed utilization, something that rapidly got leveraged out after the late Forties as everyone's passenger-centric steam designs became obsolescent).

In history, Pennsy wanted more than just a perfect Northern type...[/quote]

The real question, though, is what a 'perfect Northern type' only a few years later would have looked like, especially if WWII had not intervened and enforced the development of the Q2s and then their operation 'as intended', with long consists and allowed high speed.  It is possible that the PRR people would be watching the rebuildings of the 3751 class to see the advantages of an actual high-speed 4-8-4, but again I see little proof this influenced their design development or even measurably affected their design process.  NYC certainly came late to the party, even smart enough to recognize that high drivers could be a 'thing' and allowing adequate frame spacing, Kiefer had the locomotive built and initially tested with the 75" drivers from the corresponding designs, as if it were nothing more than an incremental capacity improvement on a 4-8-2.

, thus they "innovated" and jumped to the Q1, and then the Q2. It was quite obvious that PRR wanted to build the next-gen Super-Superpower all by itself (why not), and there was probably some discussion and negotiation between Lima, Baldwin, and PRR when they noted Pennsy was building the Q1 by its own, a dual service engine that was powerful and fast enough to handle both freight and (maybe secondary) passenger train. If the decline and dieselization never happened, all freight engine (Q2) and 50%+ passenger steam engine (T1s) would have been built by Pennsy itself (or 100% 1f Q1 was a successful dual service design). That is not something Baldwin and other steam engine builders wanted to see.[/quote]

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