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

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Posted by Jones1945 on Saturday, June 29, 2019 2:56 PM

Overmod

Draft on the bottom likely related to the direct-drive turbine, with coal bunker leading.  It is interesting to me that he does not bring up the 'Triplex' layout at all here. 

Amusing how he points out the difference in 'covering up' the two things.  We could easily extrapolate this to 1947, the year we got the C&O streamlining ... and Bikini testing... 

Gotta love the svelte Gallic curve of that question mark!

Working with Loewy's team in the 1930s must be a fun thing, but even the most talented industrial designer at the time couldn't foresee things like racing swimsuits aka competitive swimwear. (at least not in the drawing posted) Though I can understand that nude beach probably was a better fit to Loewy's lifestyle (No offense intended!) and that is a wonderful, slender question mark. Cool

The draft of the direct-drive turbine looked so much better than the finalized proposal given to the Pennsy and the C&O M-1. It is interesting to see that so much effort was put by Loewy to cover up his secret weapon... I mean his "Triplex". SurpriseCoffee 

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Posted by Overmod on Saturday, June 29, 2019 7:38 AM

Draft on the bottom likely related to the direct-drive turbine, with coal bunker leading.  It is interesting to me that he does not bring up the 'Triplex' layout at all here. 

Amusing how he points out the difference in 'covering up' the two things.  We could easily extrapolate this to 1947, the year we got the C&O streamlining ... and Bikini testing... 

Gotta love the svelte Gallic curve of that question mark!

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Posted by Jones1945 on Friday, June 28, 2019 9:05 PM

Some concept drawings by Raymond Loewy I found recently:

 

Click on the pic to enlarge

 

 

 

The draft on the bottom was probably the concept of "modern" 4-4-4-4 Camelback.

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Posted by Overmod on Monday, June 24, 2019 9:40 AM

M636C
The indicator was able to measure critical parameters and provided the best information available at the time (the late 1920s). And it was always true experimental data.

You will never hear me saying either that indicated data are worthless or that running a properly-calibrated indicator as an integral part of a test program shouldn't be done.

There is a bit of a fundamental issue here, in that a steam engine is less a "heat engine" than a pressure engine, but we call it that because heat energy is what makes the pressure that actually performs the work.  The difficulties start when people start making decisions about Rankine efficiency and heat balance based on pressure data, without doing the necessary thinking.  (This is part of why thermodynamics went to 'entropy', which has caused so many generations of students to tear their hair wondering "WHY???" without ever having it explained to them).

If you wonder, for example, what became of the French experiments with ether bottoming circa 1850... not all pressure represents the ability to do much work. In my opinion it becomes difficult to understand what a pressure measurement denotes when you are studying compression in an engine running at 9rps or higher, as the peak measurement (while of considerable importance!) is taken in such a short time interval that other effects may interfere.  [Yes, I think that this or something similar is related to what I consider the grossly-excessive dead space in the PRR Q2s and some other designs - so far as there is in fact a rational basis for it.]

I have a suspicion, without yet seeing the reference, that the 'steam flow indicator' is not actually related to event indicators at all; could it be part of the drifting arrangements on that locomotive?  I will check and confirm later.

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Posted by M636C on Saturday, June 22, 2019 6:16 AM

Overmod

 

M636C
An indicator is far from theoretical.

 

It does not measure mass flow, only secondary characteristics.  If steam were more like an ideal gas, this might be less significant, but it is not.

That said, I'd certainly rather have a set of cards from a well-calibrated indicator than not.

 

I am happy to agree that the indicator does not provide every parameter desirable for evaluation, but it does measure real locomotive characteristics and pressure against piston stroke is pretty useful.

The indicator diagrams of Paris Orleans 3566 show pretty clearly the effect of Chapelon's modifications when comparisons are made between the before and after diagrams. The differences in the indicator diagrams were reflected in tests of the locomotive's performance on the main line. While additional data might have shown more clearly which characteristics were influenced by which changes, The P-O were able to determine this by making changes to critical parts of the steam circuit without the costly poppet valves on other locomotives which showed less heroic performance improvements.

The indicator was able to measure critical parameters and provided the best information available at the time (the late 1920s). And it was always true experimental data.

Peter

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Posted by Overmod on Friday, June 21, 2019 6:43 AM

M636C
An indicator is far from theoretical.

It does not measure mass flow, only secondary characteristics.  If steam were more like an ideal gas, this might be less significant, but it is not.

That said, I'd certainly rather have a set of cards from a well-calibrated indicator than not.

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Posted by Jones1945 on Thursday, June 20, 2019 8:26 AM

Idea Crosby Indicator on 600 HP Snow Pipeline Compressor Engine

The indicator: 08:40 

 

Idea The Story of the Steam Engine Indicator

https://www.farmcollector.com/steam-traction/story-steam-engine-indicator

Coffee

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Posted by M636C on Wednesday, June 19, 2019 9:06 PM

Overmod

 

"Indizierte leistung" is just the German translation of ihp, the horsepower that a device called an 'indicator' calculates from characteristics of the valve gear.   (You can get a good idea what the device looks like, and how it works, from the Internet better than I could describe it)

The point here is that ihp, while a good theoretical number, is usually exaggerated over directly-measured wheelrim or dbhp.  Angus Sinclair had some amusing comments back in the day on how locomotives with perfect indicator diagrams sometimes failed to perform better than those with diagrams resembling 'a small leg of mutton'...

 

 

Exactly where did you study engineering?

An indicator is far from theoretical.

The indicators I was taught to use were small cylinders which rotated against a spring using small cables connected to the piston rod at the crosshead end. The stylus operated vertically against spring pressure measuring the pressure in the cylinder.

So the diagram was far from theoretical, being based on actual piston travel against actual pressure in the cylinder. However, there was plenty of room for errors of various kinds in producing a diagram, particularly on a moving locomotive.

But experimental error does not make a measurement theoretical. It is just harder to draw the correct conclusions from the data.

The best examples of indicator diagrams which clearly show the power output are Chapelon's diagrams showing high and low pressure for the P-O Pacifics before and after his modifications. The high pressure diagrams were similar, but the low pressure were entirely different.

The power is measured by calculating the area inside the indicator diagram, so the "thin" and "flat" diagrams represented low power.

The main difference between indicated and drawbar horsepower is the internal resistance of the engine itself and the power required to move its own weight. But it is an actual measure of engine power, just not the same as drawbar horsepower. 

Peter

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Posted by Overmod on Wednesday, June 19, 2019 1:10 PM

I think Reuter got his information from Arnold Haas -- probably thinking Haas was as 'expert' on PRR as he was on NYC.  The 141.2 is obviously a translation from metric (as you can quickly determine based first on the 110mph speedometer, and second on the timing precision you'd need to discriminate tenths of a mph with any stopwatch from mileposts at that speed ... one of those things that trips up a good story, like T1s with 120mph speedometers just like cars.

"Indizierte leistung" is just the German translation of ihp, the horsepower that a device called an 'indicator' calculates from characteristics of the valve gear.   (You can get a good idea what the device looks like, and how it works, from the Internet better than I could describe it)

The point here is that ihp, while a good theoretical number, is usually exaggerated over directly-measured wheelrim or dbhp.  Angus Sinclair had some amusing comments back in the day on how locomotives with perfect indicator diagrams sometimes failed to perform better than those with diagrams resembling 'a small leg of mutton'...

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Posted by Jones1945 on Wednesday, June 19, 2019 12:50 PM

Overmod
M636C
Could you indicate what aspect of the S1 you wanted information about from Reuter's book?

This was really more of a 'bump' than an actual request for something.  Anything that 'jumped out at you' as being valuable, say to Jones1945 who loves this particular locomotive, would probably be useful.

One "emergent" thing I'd like to see on 6100, although it almost certainly isn't in Rekord-Lokomotiven, is the set of acceleration curves taken with that reported 73-car freight train.  Particularly in the region above about 35mph (where the T1 was reported to 'come on the cam', as it were...)  There ought to be a 'sweet spot' in between low-speed and high-speed slipping where the engines can develop high torque with relatively little instability, and if the engine were worked strictly in this region it might have realized some of the expected potentials.

I've been showing another Trains forum member around much of New South Wales, if that is an excuse... 

I only wish I could be there too. 

I forget to mention about Reuter's book. The author says a speed record of S1 was made in March 1946 when the S1 was hauling a Trail Blazer trying to make up time. The S1 hit 141.2 mph in this run according to an ICC official's estimation. I think we heard about this story or myth too many times. Smile, Wink & Grin

I couldn't find too many "new" material about S1 in the book. Many passages are about PRR's brief history, the idea and the development of the duplex steam engine, B&O's N-1; the design, construction, operating history of S1 and its capabilities, the specification of S1, comparison of the BR 05 to S1 from a German's point of view,  T1 phototypes and Q2's brief  history...etc,.

The only interesting thing I found in this book is that the indizierte leistung of the S1 was ca.5890kW (8000 PS), which I don't know where and how the figure was obtained by the author. According to the formula used by ALCo, the power output of S1 was around 7200hp. I posted a pic before, showing how accurate the formula is. 

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Posted by Jones1945 on Wednesday, June 19, 2019 1:21 AM

Overmod

But you are forgetting the most important lesson imparted by the high-speed testing: the class J just didn't fit enough of the PRR.  Boiler was too big, for example, to run anywhere near Chicago.

Likewise you couldn't start with a Q2 boiler less one course; that was at clearance limit with only 69" ... not even 70" ... drivers.

Sorry for the late reply, what a week!  I really have forgotten the clearance restrictions in PRR's network, Mr. Overmod! Even the M1s were not allowed to operate on part of PRR's network. When Pennsy was designing the new prime steam power to rival the newly design NYCRR 100mph engine, later the S1, clearance was an important factor and Pennsy did pay a lot of attention to it. Turn out it is still exaggeratedly long and heavy.  I think we discussed before of a 4-8-4 base on the K5 and M1b, it was fun! 

 
Overmod
With the help of our forumer Reed, I have the chance to read the 7-page article about the S1 in Milepost's back issue of 1992. It seems that the wheel slip problem, probably mostly occurred at high speed, wasn't solved. There were so many wheels and drivers needed to be replaced during her short service life.

Are there answers?  Yes, and many of the ones developed for the T1 are applicable on an S1.  Even if we treat the 84" drivers in Golsdorf fashion and make no expectations of speed above the 110mph of the speed recorder, we need nothing more than proportional steam throttling off the Q2 analog-computer mechanism and lateral-acting rim brakes to solve the issue definitively.  Just that there's no point in optimizing a 140' engine that weighs as much as a Big Boy to pull just one money-losing train.

The Author, Charlie Mayer said that after the S1 racked up 161,000 miles, Pennsy "dropped at least 18 pairs of driving wheels, removed trailer wheels 8 times and engine truck wheels 4 times (within 4 years). " I suspect that the heavy loading on all axles with a bad weight distribution of the rigid frame of  S1 caused both driving wheels and tires worn out or broken within a short period of time. It is hard to believe that an engine designed by the three largest steam engine manufacturer of America made an engine that "impracticable".In hindsight, the PRR #5399 was the best answer to J. F. Deasy!

The Author also mentioned that a railfan named David A. Hill observed front engine slipping in 1944 and wrote a letter to Pennsy. His theory was that the center of gravity of S1 was higher than the drawbar line caused the engine "to rear up on its hind legs", David suggested increasing the relative weight of the front engine. Pennsy's ME replied to him patiently explaining why the problems were not easy to be solved. I wonder if this was the reason why Pennsy enlarged the sandbox on the S1 which was the only thing they could do to increase a little bit of weight on the front engine. I am looking forward to a 3D computer model of S1 which could simulate and demonstrate how slippy she was!

 
 
Overmod
          I can see the author also noted that the S1 was *probably built exclusively for the World Fair, (the whole construction progress was unnaturally kept as a secret) but he couldn't find any solid evidence to back up this point. 

The best evidence, to me, is that all the major locomotive builders conspired in the construction process.  That means the engine was intended as a kind of Four Aces on steroids, a proof of the duplex 'concept' that was over the top in the same way many show cars with over-1000-horsepower quad-turbo engines are.  It just happened that PRR wanted such an engine, and nobody else did.  So they got the demo built to their particular wishes.

I love the metaphor of Four Aces on steroids. It was so obvious that S1 was built for the global event, the 1939-40 World Fair. Oversized, overpowered, over-modded. Yes According to the Milepost magazine, one of the things Pennsy concerned a lot when designing the S1 was the clearance of the new engine which makes me believe that Pennsy and the related department of the World Fair wanted to build a steam engine which could wow the public but also could have been operating in PRR's network instead of a completely useless white-elephant. 

Overmod
The idea of the duplex, a by-product of the competition between the New York Central and PRR ...

That is almost certainly not what it came out of.  You will note that little B&O started building theirs not long after the idea was first floated, and NYC based most of theirs on PRR's second-generation design ... only to abort the whole idea before any metal was even cut or cast to make one.  

The biggest thing PRR did with duplexes, in my opinion, was how to get four rear-facing cylinders accommodated with minimal impact on the rigid wheelbase.  In a cast engine bed.  The solution on the Q2, and it was a very conscious and experienced solution, was so good that its rigid wheelbase, for almost 8000hp at high speed, is actually less than an ATSF 5011-class 2-10-4 of markedly lower capacity.  But, of course, unless you have an actual need (and commensurate bottom-line return on investment) for that kind of power, you're better off providing yourself with...

Another careless mistake of me. I should have said "the idea of S1 and T1". It would be interesting to see a chart comparing the operating cost of PRR Q2 and ATSF 5011, their TE was close but the Q2 had almost an extra 3000hp more power output than the 5011 class. In actual operation after WWII, the PRR Q2 probably seldom needed to be pushing to their limits. But I don't have the figures. 

 

Speaking of B&O's N-1, I read somewhere that one problem of it was the extra heat of the firebox affected the lubricant in the rear cylinders. I am not sure if it was the case and if the lubricant was affected, did Pennsy find the solution four years later when they were designing the Q1.

Overmod
I'd like to have seen a destreamlined version of the M-1 run, though.  That would be cool.
   Me too! It would have looked like something you can only find in Sci-Fi movie or Steampunk comic books! C&O M-1 was probably the closest thing to Nazi-Germany's Breitspurbahn. 
Overmod
I don't know if the Leader class then a-buildin' in Blighty technically counts as being in the Western Hemisphere (it would, of course, be very close even if not) but that makes an M-1 look like a gold-edged bond by comparison.  And this was FAR from the wackiest thing the little weasel inflicted on C&O, or NYC for that matter -- by the way, you have him more or less directly to blame for why there are no preserved Hudsons or Niagaras.  Just so you and Vince know.
    Good point. Hard to tell which one was the worst: the making of the Leader class in the UK or the three C&O M-1s. Equally bad I think. But at least the C&O M-1 looked cool. 
 
Overmod
What I find reprehensible is how quickly Baldwin left C&O twisting in the breeze after all the showstopping problems turned up.  But by then the diesel revolution and the free-piston extravaganza were in full swing there, and the finances going swiftly to hell.
Baldwin was really good at turning their clients or business partners into enemies than making good steam engine after WWII, I believe many railroaders or ex-railroaders at the time celebrated when Baldwin shut down. 

Overmod
Oh, there were many; they were just stillborn and then their records were lost or disposed of. 

I wish there was a book about them!

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Posted by Jones1945 on Thursday, June 13, 2019 11:32 AM

Dear Overmod and Peter, I have Reuter's book, but I can only giving short replies right now. Once everything settles down on my side, I will write a thorough reply to you guys. Thanks a lot! 

 

"I wish you would have somebody get to work designing a fast passenger engine of even greater capacity than now established.

 You will observe that the New York Central is advertising that their new engine is capable of making 100 miles per hour.

Keep me posted on the progress of the work.

J.F Deasy 

May 22, 1936 "

 

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Posted by Overmod on Thursday, June 13, 2019 6:51 AM

M636C
Could you indicate what aspect of the S1 you wanted information about from Reuter's book?

This was really more of a 'bump' than an actual request for something.  Anything that 'jumped out at you' as being valuable, say to Jones1945 who loves this particular locomotive, would probably be useful.

One "emergent" thing I'd like to see on 6100, although it almost certainly isn't in Rekord-Lokomotiven, is the set of acceleration curves taken with that reported 73-car freight train.  Particularly in the region above about 35mph (where the T1 was reported to 'come on the cam', as it were...)  There ought to be a 'sweet spot' in between low-speed and high-speed slipping where the engines can develop high torque with relatively little instability, and if the engine were worked strictly in this region it might have realized some of the expected potential.

I've been showing another Trains forum member around much of New South Wales, if that is an excuse...

I only wish I could be there too.

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Posted by M636C on Wednesday, June 12, 2019 9:17 PM

Overmod

Just as a heads-up:  At the beginning of this thread, back in 2018, Peter Clark was going to look up PRR S1 6100 in Reuter's Rekord-Lokomotiven.  I don't remember what the actual result of that check was.

Perhaps if Mr. Clark is away from the references, or if someone else wants to comment on this, here is the amazon.com listing for the book.  (There are of course other sources; it's not a 'rare book' yet.)

 

Overmod,

Could you indicate what aspect of the S1 you wanted information about from Reuter's book? I'll be back home some time next week.

I can recall pulling the book out and checkng it last year, but I may not have answered your request.

I've been showing another Trains forum member around much of New South Wales, if that is an excuse...

Peter

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Posted by Jones1945 on Wednesday, June 12, 2019 1:54 PM

Thanks a lot, Overmod and Vince! I am busy handling some people's emergency situation right now (no worries, we are ok) I will write a response to you guys later! Yes

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Posted by Miningman on Wednesday, June 12, 2019 11:27 AM

Overmod-- " by the way, you have him more or less directly to blame for why there are no preserved Hudsons or Niagaras.  Just so you and Vince know."

Well thank you for that. Have read much the same previously but no details. He certainly was an innovative and forward looking character but a victim of the times and his own addle minded visions. Did not survive the stock spiralling downward of the New York Central.  

As the adage goes " there but the grace of God go I". 

Interesting to speculate and arm chair quarterback motive power and make the necessary adjustments. A more cautious approach would not have stopped much and 1960 was just around the corner. 

Way way too much to say about that. It's in my book!

 

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Posted by Overmod on Tuesday, June 11, 2019 1:57 PM

Jones1945
I wonder how much money would have saved if PRR chose the N&W Class J instead of the duplexes. It can be calculated since the total cost of all of the duplex engines was recorded.  The Js could have been the successor of both K4s and M1s, the best dual-service steam engine ever made ... Too perfect for *me!

 But you are forgetting the most important lesson imparted by the high-speed testing: the class J just didn't fit enough of the PRR.  Boiler was too big, for example, to run anywhere near Chicago.

Likewise you couldn't start with a Q2 boiler less one course; that was at clearance limit with only 69" ... not even 70" ... drivers.

So a putative PRR 4-8-4 would likely be more like a Niagara's running gear with a slightly downsized big Belpaire boiler that would 'just fit'.  We can't use the T1 trailing truck as it's only sized for the 92' grate and structure; if you want we can modify the Q1 casting design.  While it doesn't help that Baldwin, not Alco, is the 'design partner' it does have to be said that the experience with Timken rods and bearings ... and with the #4 driver pair extended crankpins cracking on the PRR-controlled N&W ... would have produced the equivalent of NYC's 6000-hp driveline right through to the hollow piston rods, probably with centrifugally-cast pistons using the 1948 T1 valve improvement techniques.

Take the cab design off the 2-10-4 for a start; if you adjust it, do so based on crew needs rather than outside aesthetics.  (But keep those semilune windows!)

You have the same issues for the smokebox and front as with the Niagara, avoiding the Frankenstein "outer door" arrangement but of course preserving the 'beauty treatment' generator and headlight swap... perhaps with the two-light vertical Pyle treatment as applied to one of the T1s (to me it looks pretty good).  I leave it up to you whether it gets smoke deflectors, as I personally think a Niagara looks a bit like a mobile package boiler plant without them, and this is a comparable shape.

The drivers are the fun part.  Remember that 72" is M1 country and a Fleet of Modernism 4-8-4 had better have more potential; remember also that 75" on a Niagara was throwing away money and even with Central's uber-restricted loading gage they couldn't get 79" (the NYC equivalent of 80") high wheels on it fast enough.  The 77" of the Q1 would (based on documents like the review of the N&W J) be about the minimum Cover et al. would have tried; the good news here is that repurposed T1 driver centers wouldn't have worked because of the designed-in short stroke, so you have a clean slate picking high-wheel cast centers or even Web-Spoke if you swallowed ... I think Baldwin had a finger in that pie ... the Fla-Vor-Aid of that approach on the non-main wheels.  There is a sweet spot at 76" (see the H class and the aborted Lima 4-8-6s) and I'd be sorely tempted to exploit it with lightweight gear ... BUT it would leave you just that little notch down on the NYC for perceived high speed, with little or no true incremental gain over the Niagara in any aspect of running gear (since Alco already optimized it a bit too far)

 

That [a double-turbine Q] would have been a fascinating major rebuild. Though I strongly believe that it wouldn't be an economic and flexible engine which could challenge the diesel F units, it would have been a very cute white-elephant. A Q2 size welded boiler, a chassis long enough for 4-10-4 or 4-10-6, V1-style turbines, alloy steel rods, 70+ inches drivers with the best balancing, roller bearings here and there, anti-slip control, an attractive semi streamlining.

As a side note: you need neither the high drivers nor the 'best balancing' on one of these turbines, as the drive is almost entirely balanced and there is of course no overbalance surge.  There are a couple of ways, including a modification of the Langer balancer, to get around the quartered augment of the side rods used; as you probably know, the S2 originally had coupling rods only on the outer pairs, but very quickly acquired a full set, so we know more about the gear arrangement than history lets on, so we design from the start for full rod beams per side plus thin Timken bearings, run as close inboard as we can make them.  That's really good enough for any practical PRR working speed, which was over 90mph for the 68" drivers on the S2, especially since much of the mass advantage from the duplex principle carries over to conjugating rods in a lateral direct-drive turbine layout.

You likely wouldn't use V1 style turbines (unless the V1 design was jiggered by Westinghouse to be usable in the transverse configuration, which at the least would require some interesting exhaust-plenum design).  From what we know, those were axial-flow and fairly long, with lots of room at the LP end for good exhausting.  What you would want to use instead would be something like a paired-turbine arrangement (symmetrical around the main pinion in the center) -- HP admission inboard, with relatively short and inflexible HP branch manifold that easily clears the spring rigging, and large outside plena and exhaust trunking.  Since you have what are in essence four blade nests, they can individually be very small; of course they are in two sizes but most of the blading itself will be common.

Reverse in this design is NOT via a separate geared turbine, it would be via an interposed idler in the main gearbox and bath.  Since this would not move other than 100% from forward to reverse, it is unlikely to require either 'sprung' construction or heavy shock-tolerant mounting; it will be as high up in the gear train as possible to reduce tooth and stress forces (which is fine because we care little about how fast the idler will have to spin).  Important for a dual service engine: you have the same torque, responsive to the same throttle adjustment, in reverse as you do in forward; if you want to design the engine for bidirectionality (with, for example, FM-TV from the end of the Castor/Aphrodite project for vision off the tender) you certainly could.  The main implication is for the trailing truck: it will need to be stable in guiding in both directions, which a normal Delta trailing truck really isn't.  I leave this as a solution for the alert reader.

 

I am still obsessed with the 6-wheel truck design.

Don't be.  Unless you have to -- and I suspect with the more 'efficient' firebox and chamber construction you will have to. 

Just as a point: the six-wheel truck costs.  In the first place, for construction and fabrication with additional mass and casting complexity.  In the second place, with 150% additional tread and brake-rigging wear.  You lose length, have increased swing, need better steering and weight-transfer accommodation at the rear, and all for what? the ability to blow through water faster and have to make more stops.  The only real advantage is the weight-bearing capability ... and weight minimization is always a good idea on modern power, especially toward the rear; you can use every pound for better auxiliaries or better circulation.

The point here is that a good modern boiler will have some version of Snyder combustion-air preheaters, which are like coils of brake-air 'radiator' pipe in weight, and a full Cunningham circulator, which involves saturated-water manifolding nearly the length of the water legs with multiple ports and vanes into the waterspace.  Consider this all (on a PRR 4-8-4 design) completely aft of the rear drivers for weight-distribution purposes.

If the 4-wheel trailing truck of the Q1 could be replaced by the 6-wheel truck, it would have had more space for a larger firebox or provided more room for a completely new firebox design without sacrifice the room of the cab.

Something I guarantee you will NOT need or want is a "larger firebox", at least larger in terms of grate area.  That needs to be about 100 to 104' ... but... you have the thermodynamic gains from the air preheat and then the enhanced radiant-section circulation, each accounting in tests for about a 10% increase in boiler steam-generation efficiency and neither affecting much of the potential gain from the other.  Add to this the practicality of operating with sliding-pressure firing while maintaining full superheat to the turbines and you wind up with little need to go to enormous, heavy, water-filled structure or increase the actual radiant uptake surface dramatically to try to take advantage of the higher grate limit from a larger box.  Fuel costs; if the additional fuel is used to boil 'more' water, the water costs; delivery of both to an engine in service is the chief rock that sank big advanced turbine steam on PRR in the first place.

But that means my fantasy white elephant would have been as gigantic as the S1 (Cool!).

Cool, yes.  Necessary, no.  You will note that none of the Lima six-wheel-trailer proposals had need of equally long structure at the smokebox end; in fact, the more advanced ones were only 2-8-6s (in part to gain back the length and reduced siding capacity imposed by the six-wheel rear truck).  Since the firebox improvements are mostly spring-borne by the trailer arrangements and only secondarily equalized with the drivers, there are no implications other than some inertial-accommodation issues with having relatively little weight forward of the third driver pair compared to the rear, even at high speed.

Now PRR for reasons of its own will insist on a pin-guided leading truck.  In my opinion what you'd get on a converted Q1 (which of course no longer has its cylinders to require low truck sideframes or outboard clearance) would be an adapted T1 outside-frame engine truck.  If you wanted to have some fun here, I suspect you could easily hang one of the air compressors per side neatly in the space where the front engine cylinders had been, giving you all the accessibility needed and involving only slight adjustment to the brake piping.  Then if you wanted to see if an ACFI heater arrangement works better than, say, Worthington you have room for it on the pilot beam. 

 

However, I think they were not powerful nor fast enough in my fantasy world!

Even in a fantasy world, you have to remember the implications of basic physics and the assumption (in part driven by your stockholders) to get the greatest revenue (long-term, too) from a given capital investment.  That means picking the least cost per reliable horsepower, and efficient operation over the range of loads and speeds that your railroad's profile and anticipated trainload characteristics impose.

The good news is that a PRR 4-8-4 or 4-8-6, turbine or otherwise, is unlikely to be more than a M&E 'dual service' engine; it specifically can be designed to spend a high percentage of its service life at or close to design speed with an appropriate load behind it -- the same criterion that made the Niagaras so famous and so able to run up high reliable mileage.  Now, if we utilize some of Voyce Glaze's balancing conventions in a relatively high-wheel 4-8-4 we begin to have an engine PRR had little practical need for ... but was beginning to look at definite applications for.  By the mid-Fifties this would have been right in the sweet spot for passenger-trucked TrucTrain consists ... run 'em as fast as the trailers will take.  This in the same timeframe the Nickel Plate could make Berks pay with conventional interchange car trains.  Makes you think, doesn't it?

 

With the help of our forumer Reed, I have the chance to read the 7-page article about the S1 in Milepost's back issue of 1992. It seems that the wheel slip problem, probably mostly occurred at high speed, wasn't solved. There were so many wheels and drivers needed to be replaced during her short service life.

Now this is important: did he say "drivers" or "driver tires"?  And note that the enormous inertia of the locomotive, and the long distance from the truck pivot to the leading driver flanges, didn't make it easy for slip forces to be accommodated when (not if) they developed.

Are there answers?  Yes, and many of the ones developed for the T1 are applicable on an S1.  Even if we treat the 84" drivers in Golsdorf fashion and make no expectations of speed above the 110mph of the speed recorder, we need nothing more than proportional steam throttling off the Q2 analog-computer mechanism and lateral-acting rim brakes to solve the issue definitively.  Just that there's no point in optimizing a 140' engine that weighs as much as a Big Boy to pull just one money-losing train.

 

I can see the author also noted that the S1 was *probably built exclusively for the World Fair, (the whole construction progress was unnaturally kept as a secret) but he couldn't find any solid evidence to back up this point.

The best evidence, to me, is that all the major locomotive builders conspired in the construction process.  That means the engine was intended as a kind of Four Aces on steroids, a proof of the duplex 'concept' that was over the top in the same way many show cars with over-1000-horsepower quad-turbo engines are.  It just happened that PRR wanted such an engine, and nobody else did.  So they got the demo built to their particular wishes.

 

The idea of the duplex, a by-product of the competition between the New York Central and PRR ...

That is almost certainly not what it came out of.  You will note that little B&O started building theirs not long after the idea was first floated, and NYC based most of theirs on PRR's second-generation design ... only to abort the whole idea before any metal was even cut or cast to make one.  

Think of the duplex as the last gasp of '20s-style design, aimed at increasing practical horsepower and capacity through multiple cylinders while reducing old-school augment force on the track, and keeping all the cylinders and presumably their valve gear nicely outboard and familiar to maintenance forces.  For 1933 it was a marvelous innovation; the point was that better ways to achieve high horsepower out of a 4-8-4 were only just being practically tested out -- with one glaring failure still almost a half-decade in the future.

The biggest thing PRR did with duplexes, in my opinion, was how to get four rear-facing cylinders accommodated with minimal impact on the rigid wheelbase.  In a cast engine bed.  The solution on the Q2, and it was a very conscious and experienced solution, was so good that its rigid wheelbase, for almost 8000hp at high speed, is actually less than an ATSF 5011-class 2-10-4 of markedly lower capacity.  But, of course, unless you have an actual need (and commensurate bottom-line return on investment) for that kind of power, you're better off providing yourself with...

 

Pennsy low key constructed  4-8-4s based ... on their own M1s or K5...

Would have been nice to ream out important gage restrictions on suitable main lines to make larger engines possible.  In particular had the stack revolution started at the end of WWII instead of waiting until the '70s, the additional clearance could have made a high-wheel class J a practical thing.  Of course it would be impossibly top-heavy and head for the ditch every chance it could take, but that's another story...

It is interesting to consider what an improved Mountain could have offered PRR -- or more precisely what you'd get by putting a modern welded boiler together with Snyders and Cunningham on an M1a with a lower back-pressure front end.  Remember the extra axle for carrying?  Now you have a locomotive with appropriate cylinder capacity needing only the lightweight running gear to thrive ... and how many of them had PRR (over)bought by the Depression era?

And disc mains on 72" with the lightweight gear is all the improvement needed for balancing up well past 110mph...

Just no fun even thinking about streamlining one, let alone a fleet of them.  Could be done, of course, but it's a waste of the weight, much like the Blue Goose shroud slated for ATSF 3765.

 

I really don't understand the transaction between C&O and Baldwin for the M-1 turbine electric...

It's really simple: Baldwin essentially lied through their teeth to get C&O to buy in to their project for a 6000hp single-unit turbine.  Probably pointing over at the idea of N&W getting modified V1s, which is still one of those inexplicable road-not-taken stories of the mid-1940s.

Now, I'd thought (from reading the story on the Chessie in Trains) that one of the ideas behind that train was that it would be a rolling palace, something like 32 cars long assembled outside its origin station and disassembled and multiple-switched into adjacent tracks on arrival.  A train that size going over C&O's grades needs a steam-turbine electric of that size to avoid double-heading or worse, even if we ignore all the slipping and other limitations of 2-cylinder simple steam locomotives doing that job.

It turns out that the plans were scaled back (and nearly everyone could get C&O ordered cars for a good price up to a couple of years later!) and of course nobody really needed a supertrain to Cincinnati (just ask B&O and N&W, who actually geared up for the potential competition in this period but to my knowledge didn't make anything much out of it) so it wound up being the capacity to take a train quicker over the mountains that could then be handled by, say, a 490-class streamlined Hudson on the flatter portions.  And I really don't doubt that Baldwin told them the same lie they told N&W over the 'final solution' TE-1 design: that it was capable of high horsepower at 65mph or better.

Which of course it wasn't -- neither of them was.  The turbine is relatively fixed-horsepower as designed, if it has to exhaust to atmosphere; even if it weren't, the output is pegged by generator capability.  And by traction-motor limitations.  Even in the absence of conductive and abrasive coal dust and liberal amounts of moisture and high sulfur in some of the coal... and so on.

A full-welded boiler, already becoming a trade possibility as the M-1s were being assembled, might have helped the design.  But little in the driveline was going to 'thrive', and practical alternatives would have involved technology that really didn't mature until this century. 

I'd like to have seen a destreamlined version of the M-1 run, though.  That would be cool.

 

... for C&O's management led by Robert Ralph Young, it was probably one of the most reckless decisions ever made by the leader of a class I railroad in the western hemisphere.

I don't know if the Leader class then a-buildin' in Blighty technically counts as being in the Western Hemisphere (it would of course be very close even if not) but that makes an M-1 look like a gold-edged bond by comparison.  And this was FAR from the wackiest thing the little weasel inflicted on C&O, or NYC for that matter -- by the way, you have him more or less directly to blame for why there are no preserved Hudsons or Niagaras.  Just so you and Vince know.

 

I won't be surprised if all three of them were actually gifted to (or 70% off) C&O but I am just assuming and do not want any people getting offended.

You know, I never even thought about that angle. 

My guess is Baldwin got full price both for 'development' and construction, as C&O was a cash-rich 'sucker' with only incidental exposure to more than conservative motive-power development up to that era.  More interesting is that even an 'improved' J-3 type Greenbrier wouldn't have been capable of the turbine's anticipated performance; it's difficult to imagine any eight-coupled doing the work or any ten- or twelve-coupled making the time.

What I find reprehensible is how quickly Baldwin left C&O twisting in the breeze after all the showstopping problems turned up.  But by then the diesel revolution and the free-piston extravaganza were in full swing there, and the finances going swiftly to hell.

 

When we read about the history of many class I railroads which survived the decline, they seldom or never introduce any experimental steam engine during the transitional era...

Oh, there were many; they were just stillborn and then their records were lost or disposed of.  You'd have seen quite a bit more interesting steam in the late '40s and perhaps into the early '50s had GM not bought EMC and Winton in the early Thirties and then turned those talented people loose on commercializing large road power.  I for one would have liked to see exactly what LV planned to do with a Q2-style duplex in a world where Alco and Baldwin weren't spurred to diesel production and Lima wasn't castrated in a merger-of-convenience.

 

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Posted by Jones1945 on Tuesday, June 11, 2019 11:18 AM

Overmod

I suspect the major contribution of the Q2s to the Korean War (which started in 1950) was the alloy steel and other metals in their composition.  Were any even seriously running at that point?

This is probably the truth, Mr. Overmod. Although most of them were not retired by 1953. The S2, Q1 and the Q2 phototypes were all dropped from the roster in Jan 1952. Compared them to other freight engines in the PRR system, steam, electric and diesel, Q2's contribution to the Korean War were negligible. I think it was discussed many times before but it would be nice to review the history of railroading during the Korean War if our forumer could share with us their first-hand experience or research. 

I wonder how much money would have saved if PRR chose the N&W Class J instead of the duplexes. It can be calculated since the total cost of all of the duplex engines was recorded.  The Js could have been the successor of both K4s and M1s, the best dual-service steam engine ever made. But sometimes the reality is a playground of no-fun-allowed, this is why I still love Q1 and Q2 better than the Js (both N&W & PRR). 

Too perfect for *me!

Overmod
In my opinion, had there been no turbines we might have seen some attempt to de-sow's-ear the Q1, probably involving a switch to smaller drivers and perhaps some rebushing of the cylinders to adjust the cyclic water rate upward to suit (and perhaps some application of RC poppet gear in a reverse T1a change to three-valve Franklin type C as on ATSF 3752, but I doubt it).  At this point I am tempted to speculate a bit and note 'what if we put a welded boiler and better firebox on the chassis, and geared in a couple of smaller V1-style turbines with the full-proportional version of the Q2 slip control' which still wouldn't have solved the lethal water-rate problem but would give us a highly interesting testbed... just don't expect Baldwin to build the pieces. 

I suspect much of the correspondence over the design options here would make interesting reading

That would have been a fascinating major rebuild. Though I strongly believe that it wouldn't be an economic and flexible engine which could challenge the diesel F units, it would have been a very cute white-elephant. A Q2 size welded boiler, a chassis long enough for 4-10-4 or 4-10-6, V1-style turbines, alloy steel rods, 70+ inches drivers with the best balancing, roller bearings here and there, anti-slip control, an attractive semi streamlining.

I am still obsessed with the 6-wheel truck design. If the 4-wheel trailing truck of the Q1 could be replaced by the 6-wheel truck, it would have had more space for a larger firebox or provided more room for a completely new firebox design without sacrifice the room of the cab. But that means my fantasy white elephant would have been as gigantic as the S1 (Cool!). Yes, I admit that the duplexes of Pennsy were white-elephant outside my fantasy world. It wasn't because they had a bad design, but there wasn't a strong need to build such a powerful engine after the war in the PRR's network, in hindsight once again. 

However, I think they were not powerful nor fast enough in my fantasy world!

 A GTW 4-8-4 with one more pair of the driver

Overmod
PRR was, according to some of the notes at the Hagley, proud of the way it handled the steam'pipe and snifting valve arrangements at the rear of the Q1 to avoid the kinds of problems B&O had on their locomotive.  If you look at it from pure engineering, they did a pretty good job.  Just that nobody told the steam, and the dirt, and the things in casual collision with items located near the limits of the loading gage, about how to respect products of superior intellect ... as it were.

I am delighted to know that PRR Motive Power actually knew what they were doing when designing the Q1 since many critics Pennsy repeated the same mistake of B&O's N-1. Even though it was not good enough to be mass produced, but in Baldwin's eyes, the Q1 was at least a symbol of Pennsy's bargaining power, a potential competitor to Baldwin's ill-fated duplex product. 

With the help of our forumer Reed, I have the chance to read the 7-page article about the S1 in Milepost's back issue of 1992. It seems that the wheel slip problem, probably mostly occurred at high speed, wasn't solved. There were so many wheels and drivers needed to be replaced during her short service life. I can see the author also noted that the S1 was *probably built exclusively for the World Fair, (the whole construction progress was unnaturally kept as a secret) but he couldn't find any solid evidence to back up this point. 

The idea of the duplex, a by-product of the competition between the New York Central and PRR, was one of the most expensive, overbudget drama in NA's railroading history. If Pennsy low key constructed a 4-8-4s base on the N&W Class J or their own M1s or K5, Pennsy would have had won hands down.

Overmod
...Baldwin, seeing its own future more than a little closely aligned with that of Steins et al., decides to implement its own 'hush-hush' design effort to end-run around the Steins patents ... the result of which comedy was (as no one I suspect will be surprised to learn) the C&O M-1 turbines.  (In case you were wondering why there were three, and so little testing was done to debug the first one...)  This essentially threw down the gauntlet to PRR Motive Power in a way that makes it potentially easier to see why no further direct-turbine work was undertaken at that critical time that turbine steam power was the wave of the future... and the compound-expansion answer to the whole double-maintenance problem of the duplexes at a stroke...

I really don't understand the transaction between C&O and Baldwin for the M-1 turbine electric, I can understand why Baldwin rushed the fubar M-1 before PRR's "Triplex" can be built, but for C&O's management led by Robert Ralph Young, it was probably one of the most reckless decisions ever made by the leader of a class I railroad in the western hemisphere.  I won't be surprised if all three of them were actually gifted to (or 70% off) C&O but I am just assuming and do not want any people getting offended.

When we read about the history of many class I railroads which survived the decline, they seldom or never introduce any experimental steam engine during the transitional era, that was a tough time for the whole industry, steam and diesel engine development were struggling (except EMD), traffic is declining, trackage and engine worn out, passenger had way more travel options than before, risky investment was not a normal option, but somehow, the fubar M-1 was born in this era. 

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Posted by CSSHEGEWISCH on Tuesday, June 11, 2019 10:05 AM

Overmod

That doesn't mean that losing All That Steam so quickly isn't a shame for all us non-railroaders at trackside.  Tracksiders pay few bills and incur few responsibilities, but they know what they like.

 
I only saw a handful of NKP 2-8-4's in regular service so I don't miss steam, you don't miss what you didn't see.  I've always enjoyed diesels and straight electrics and relish the varieties of each.  I also enjoy seeing what's new.
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Posted by Overmod on Monday, June 10, 2019 12:36 PM

Just as a heads-up:  At the beginning of this thread, back in 2018, Peter Clark was going to look up PRR S1 6100 in Reuter's Rekord-Lokomotiven.  I don't remember what the actual result of that check was.

Perhaps if Mr. Clark is away from the references, or if someone else wants to comment on this, here is the amazon.com listing for the book.  (There are of course other sources; it's not a 'rare book' yet.)

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Posted by Overmod on Monday, June 10, 2019 12:35 PM

.

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Posted by Overmod on Monday, June 10, 2019 12:25 PM

CSSHEGEWISCH
What folly??  Sticking with an overdesigned steam locomotive in an attempt to make up for lost time caused by ignoring improvements not originated by PRR?

You have to put the folly in context.  F units were demonstrably better than anything PRR had in the steam-development pipeline, and most of the first-generation follies involved taking nearly-untried competitive approaches (244-engined FAs being one that comes to mind more forcefully than any four-axle Baldwin power, interestingly enough) that were not built following EMD's design and quality paradigms.  So the argument isn't dieselization -- that was established definitively by 1949 by the economic forces only becoming evident by about 1947 -- just incompetent dieselization forced by "the market".

Although I often moan about it, PRR fixed this problem pretty definitively in 1963, when they bit the bullet and got rid of all the old 'orphan' units, even those that were running reasonably well in service or had 'rebuild potential' (the BP-20s in particular as I've noted offering some interesting possibilities).  It is difficult to imagine working a railroad with steam, any steam, as well as it could be worked with SD40s, let alone SD40-2s ... and we need not go much more modern than that.  There are reasons not one of the modern-steam-revival programs, including those I participated in, went much of anywhere, and those reasons only get stronger each year.

That doesn't mean that losing All That Steam so quickly isn't a shame for all us non-railroaders at trackside.  Tracksiders pay few bills and incur few responsibilities, but they know what they like.

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Posted by Jones1945 on Monday, June 10, 2019 11:10 AM

Oh my! Thank you for your amazing response, Overmod. I will need some time to write a thorough response to your awesome post.

Using Q1 or even S1 as a test bed to further the steam engine development is one of my fantasy. On the other hand, I am still trying to figure it out what really happened between the PRR, Baldwin (& Westinghouse), Loewy, GM, etc. Even though we already know the official stories. 

When critical information is inaccessible on my side, imagination mixing with logical reasoning might bring me closer to the truth. 

Coffee

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Posted by Overmod on Monday, June 10, 2019 10:34 AM

Jones1945
The Q2 and T1 actually participated in two global conflicts, at least. The Korean War somewhat extended Q2 and many steam engines' service life of different railroads.

I suspect the major contribution of the Q2s to the Korean War (which started in 1950) was the alloy steel and other metals in their composition.  Were any even seriously running at that point?

It would be highly interesting to see where the T1s were used, and how useful they were (even in the sense of allowing other steam or diesels to work more strategic services).  Again, though, this was probably into the equipment-trust-saving part of the T1 retention effort, so I wouldn't expect much voluntary reactivation of stored power for main trains or other explicit wartime traffic.

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Posted by CSSHEGEWISCH on Monday, June 10, 2019 10:19 AM

Miningman

Followed of course by rows and rows and rows of unreliable super high cost Diesels that didn't last much longer than the Q1 and Q2's. 

Wonder if someone was hauled on the carpet for this unbelievable folly.

What folly??  Sticking with an overdesigned steam locomotive in an attempt to make up for lost time caused by ignoring improvements not originated by PRR?

Most PRR diesels lasted until they were fully depreciated (15 years) or even longer.  Except of course for such disasters like Baldwin's Centipede.

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Posted by Jones1945 on Monday, June 10, 2019 9:56 AM

Miningman

Very short lived and under utilized (165,000 miles). Do you remember 2015? Of course, seems like yesterday almost.. from then until now that's how long it lasted. 

Q2's fantastic performance and as Overmod calls them " win the war now locomotives" also ridiculously short lives. 

Definitely, Miningman. The Q2 and T1 actually participated in two global conflicts, at least. The Korean War somewhat extended Q2 and many steam engines' service life of different railroads. 

I do remember many details happened in my private life as well as my civil service in 2015, but there is one thing I almost can't remember its existence, which is justice. 

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Posted by Overmod on Monday, June 10, 2019 9:24 AM

Jones1945
Pennsy could have built their own duplex and set the price of the new engine independently, that means Baldwin would have lost their largest client. If Pennsy really had such intention, once Pennsy obtained all the data of the S2 turbine, as well as the T1s, they would have ditched Baldwin afterward. How Baldwin would have had reacted to such a situation? the plot thickens...

To paraphrase the sense of the Easter service, 'thickens indeed'!

Baldwin was a principal player in the 'intellectual property' development of the duplex idea (perhaps overly so) -- this being one of the key post-Eksergian efforts to eliminate the evil effects of augment.  How much the railroad world was pawing around in the half-dark is evidenced by the infamous R1 story; how clearly they got a good answer is not much later (in the 'refit kits' on, for example, the T&P 2-10-4s, the rebuilt 3751 class; the double rebuilding of the Hs into world-class glory matched (imho) only by the Niagaras).  But in the world of the Q1, anything larger than -- say -- the M1a was going to be hopeless at dual-service speed, and so...

There's an old riddle about 'what's a camel?'  The answer to which is 'a horse designed by a committee'.  Here's PRR designing a 5/4 M1 but deciding to get more and more carried away with the fun, evidently forgetting Leonor Loree's lesson about practical technology on the way.  

Part of the 'key' here is to note why the driver size was ramped up all the way to 77" instead of using disc centers and better balancing at 72". -- it's highly likely lower water rate a la Golsdorf was not part of that design decision, considering the priorities in the Q2 and V1 designs.  Instead, as in the B&O locomotive (and I suspect the putative ATSF 6-4-4-4) you have conventional drive on normal wheels which now can have smaller balance weights and overbalance consequences.

PRR was, according to some of the notes at the Hagley, proud of the way it handled the steam'pipe and snifting valve arrangements at the rear of the Q1 to avoid the kinds of problems B&O had on their locomotive.  If you look at it from pure engineering, they did a pretty good job.  Just that nobody told the steam, and the dirt, and the things in casual collision with items located near the limits of the loading gage, about how to respect products of superior intellect ... as it were.

End result is interesting precisely because the design didn't try to do what the Q2 did, produce very high horsepower at elevated speed, so you wound up with a super locomotive hobbled by just the wrong constraints to realize the promise of the 'good bits'.  Most of the issues of backpedaling drive were not particularly difficult to address (ahem, cough, cough, cab-forwards?) probably including the issue of crap rammed into the multiple-bearing crosshead surfaces, so you may be looking at T1-failure-duplicitous levels of railfan-led-by-the-nose mythology there.  On the other hand, limiting the locomotive to M&E as its prospective 'dual service' (in a world where PRR freight never topped 50mph) can be seen without particular reference to accurate hindsight as a relative waste of time and money.

Nobody seems to have thought very carefully that a locomotive that required the same cylinder care and maintenance as two M1s had better be capable of doing more things better than two M1s as possible (particularly if it cost more than three M1s to build, but I digress).  We see the same issue repeated for the Q2s as soon as no one needed 150-car trains pulled at meteoric speed over wartime-maintenance track: in a normal PRR world, the J1a (no slouch of a design itself, particularly with the upsized driver diameter) did about everything a Q2 could do on any particular practical train but with Ferrari-level maintenance for Ferrari performance the job no longer called for.

MEANWHILE ... back to the Baldwin story.

You will remember how the order for the T1s was split, half to Baldwin and half to Altoona, with the expensive valve-gear and technological bits outsourced (so Baldwin had no technological 'lock' on the market as they would have, via their controlling Westinghouse connection, on steam turbines).  Behind the scenes, here comes the future! as Steins et al. duke it out with Loewy over the 'triplex' plan and then develop the magic solution that would replace reciprocating steam with a three-box configuration that didn't involve Baldwin Locomotive Works.  (Although it did involve Westinghouse, about which more anon).

Baldwin, seeing its own future more than a little closely aligned with that of Steins et al., decides to implement its own 'hush-hush' design effort to end-run around the Steins patents ... the result of which comedy was (as no one I suspect will be surprised to learn) the C&O M-1 turbines.  (In case you were wondering why there were three, and so little testing was done to debug the first one...)  This essentially threw down the gauntlet to PRR Motive Power in a way that makes it potentially easier to see why no further direct-turbine work was undertaken at that critical time that turbine steam power was the wave of the future... and the compound-expansion answer to the whole double-maintenance problem of the duplexes at a stroke.

In my opinion, had there been no turbines we might have seen some attempt to de-sow's-ear the Q1, probably involving a switch to smaller drivers and perhaps some rebushing of the cylinders to adjust the cyclic water rate upward to suit (and perhaps some application of RC poppet gear in a reverse T1a change to three-valve Franklin type C as on ATSF 3752, but I doubt it).  At this point I am tempted to speculate a bit and note 'what if we put a welded boiler and better firebox on the chassis, and geared in a couple of smaller V1-style turbines with the full-proportional version of the Q2 slip control' which still wouldn't have solved the lethal water-rate problem but would give us a highly interesting testbed... just don't expect Baldwin to build the pieces. 

 I suspect much of the correspondence over the design options here would make interesting reading

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Posted by Miningman on Sunday, June 09, 2019 4:48 PM

Very short lived and under utilized (165,000 miles). Do you remember 2015? Of course, seems like yesterday almost.. from then until now that's how long it lasted. 

Q2's fantastic performance and as Overmod calls them " win the war now locomotives" also ridiculously short lives. 

Followed of course by rows and rows and rows of unreliable super high cost Diesels that didn't last much longer than the Q1 and Q2's. 

Wonder if someone was hauled on the carpet for this unbelievable folly.

Don't think so, they were all in on it, and couldn't rid themselves of their steam fast enough. Blink and you missed it all. 

Nothing new here that hasn't been stated previously but the whole thing S1 thru to T1's was a darn shame. When Pennsy turned its back on its best moment and then destroyed it all what can you say besides ridiculous.

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Posted by Jones1945 on Sunday, June 09, 2019 3:01 PM

(For the record) I never heard about this but I just found out that the S1 once hauled a 90-car freight consist and hit 73mph during a test outing, according to the Keystone Magazine Vol.27, No.2, summer 1994. I don't think we discussed such testing of S1 before but the T1s towing freight train for testing was mentioned in several posts. 

If that road test was conducted during the break of the World Fair, the result of it might affect the design of Q1 later in 1940. Many say that the 77" drivers on Q1 were too large for a freight engine (It was a dual service engine actually) but the result of S1 towing the 3600 tons (presuming all cars were loaded, 40-ton* 90) freight train probably encouraged Pennsy to not using the smaller driver on the Q1.

I still believe that Q1 was one of the most ambitious plans of Pennsy during the transitional era. If the Q1, as the successor of the M1s 4-8-2, was good enough to be mass produced, the PRR didn't even have to cooperate with Baldwin or other steam engine manufacturer anymore. Pennsy could have built their own duplex and set the price of the new engine independently, that means Baldwin would have lost their largest client.

If Pennsy really had such intention, once Pennsy obtained all the data of the S2 turbine, as well as the T1s, they would have ditched Baldwin afterward. How Baldwin would have had reacted to such a situation? the plot thickens...... Movie Coffee

Designed and built by PRR.

^The supposed to be the new Pennsy face, designed by Raymond Loewy and altered on Clement's request.  

Fast, strong, flexible and stylish. 

Not as slippy as the T1s,

not as oversized as the S1,

dual services ready,

built by Pennsy's own shop,

the mother of the Q2s,

long forgotten outside this forum......

 

Jones Family Railroad Hobby YouTube Channel
https://www.youtube.com/channel/UCu9gt9Q9RF-Hwq7xWciVcWg/

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