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

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Posted by Miningman on Monday, August 6, 2018 11:28 PM

It even illuminates the track it is on. 

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Posted by Jones1945 on Monday, August 6, 2018 11:18 PM

Overmod
....Now, if you look at PRR slang carefully enough, you'll see that 'snapper' was not just a regional term for helper service -- PRR had both 'helpers' and 'snappers' and they were not just distinguished by their location in a consist (although that is functionally important).  

Smile, Wink & Grin

The largest, heaviest and most expensive "helper" the PRR ever purchased. It was supposed to perform as good as GG1, the preferred engine of the Blue-Ribbon Fleet. Its size fitted PRR’s taste, big enough to wow its rivals, but turn out they were one of the biggest flops in America Railroad History. (source: Railroad Museum of Pennsylvania, note the passenger cars were still carrying the FOM scheme)

 

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Posted by Overmod on Monday, August 6, 2018 2:58 PM

daveklepper
Yes,routinely K4s were double-headed, especially Harrisburg-Pittsburg(h). (Often through to Crestline.) Never saw triple-heading though.

The double-heading was to create the effect of a single large road engine for very heavy Pullman consists (on the order of the 1000-ton train in the S1 spec), the rationale being the very large number of available locomotives (even more with the progression of the electrification).  In fact it would be possible to doublehead a couple of E6 locomotives and save some costs ... as mirrored in the early planning and use of the O-class electrics or a bit later in the T1 design ... but the great 'standardization' was made in the Twenties, sized to perceived requirements then, and however much a mistake it was to do that, there were far more K4s available for 'fungible' use building passenger consists essentially greater than anything possible with Algerian-Garratt style articulateds.  (And as noted, the crews would like All Those Extra Hours Every Hundred Miles On Every Train, too).  Then the size of your available train becomes constrained by things like platform length or walk to the diner, not horsepower, except in one critical respect.

That respect being getting over the fixed maximum restriction on PRR, the grade over Gallitzin including Horse Shoe.  This is where even the 'vanity cushion' of a twelve-coupled locomotive doesn't provide quite enough power to maintain road speed for the few miles of steep grade, and the third K4 would come into play.

Now, if you look at PRR slang carefully enough, you'll see that 'snapper' was not just a regional term for helper service -- PRR had both 'helpers' and 'snappers' and they were not just distinguished by their location in a consist (although that is functionally important).  You need to distinguish what the extra TE and horsepower is meant to do.  If you add locomotive power to enable a heavy train to make it 'over the hill', you have a helper.  If you add locomotive power to enable a heavy train to make time 'over the hill' comparable to, or at least faster than, the train can make on either side, you have a snapper.  And the selected class of snapper locomotive can't be, say, like the 2-10-2s used to drag diesel streamliners up the likes of Cajon; they have to be smooth-riding at the speeds expected.

So if snapping were desired, as on one of the 'first-class' trains, you might expect triple-heading, but only over certain divisions.  Otherwise expect the fact of the double-heading to be able to maintain reasonable (albeit lower) speed, or the ability to traverse Horse Shoe without external helper, for less extreme or less demanding trains.

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Posted by Jones1945 on Monday, August 6, 2018 10:30 AM

daveklepper

They should have been envious of the Central's "Water-Level" route,  It was that, more than superior motive power, that avoided double-heading on the Central.

Yes,routinely K4s were double-headed, especially Harrsburg-Pittslbugh.  (Often through to Crestline.)  Never saw triple-heading though.  Have any evidence?

I read some articles mentioned about Triple-heading K4s, probably happened during World War II at the Horseshoe curves, but I never have seen any photographic or video evidence so far. Triple-heading after the war must be as rare as a double-headed T1 (jk).

Btw, many think that PRR T1 was not welcomed by the crews because it replaced double-headed K4s; an operating arrangement which ensured their living hood. 

 

Smile, Wink & GrinIn case you missed some "K4s action":



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Posted by daveklepper on Monday, August 6, 2018 9:44 AM

They should have been envious of the Central's "Water-Level" route,  It was that, more than superior motive power, that avoided double-heading on the Central.

Yes,routinely K4s were double-headed, especially Harrsburg-Pittslbugh.  (Often through to Crestline.)  Never saw triple-heading though.  Have any evidence?

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Posted by Jones1945 on Sunday, August 5, 2018 10:22 AM
3rd rail
The Pennsy guys were a bit envious of the NYC Hudsons just to their north... It took two, sometimes three, K-4's to get a passenger train across the Alleghenies, while the "Central" whisked along with a single J-3.. At 90 mph.. 
 Now, John talked about running a T-1 from Crestline OH, To FT. Wayne IN hitting over 100 mph, but I can only imagine...   Look at that line today.  Weeds  and rotten ties. Ah, what a shame....... 
Todd
 
Interesting point of view from the crew of PRR, Todd. I agree with you that K4s was probably the best steam engine PRR ever had, although many crew love M1 even more.  

The Tractive Effort of PRR K4s, (a Pacific 4-6-2) were even higher than NYC J-3 (a Hudson 4-6-4) without a booster, I have seen quite a lot of videos, some available on YouTube, showing a single head Streamlined K4s running at 80+ mph with 8-10 cars behind. K4s didn’t even need a booster to start a heavy train, S1 and T1 also didn’t need it, since they can make up time at 100mph+ whenever and whatever they want. Time

Wheel slip problem of S1 and T1s has been discussed for 70 years after more and more documents like operating records and testing report revealed in recent years, it's almost a consensus that their wheel slip problem was exaggerated and wasn’t uncontrollable.
 
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Posted by 3rd rail on Sunday, August 5, 2018 7:50 AM

WELL, While they were pretty to look at, I heard it from the "Horses Mouth" (John Crosby) who was an engineer on the Ft.Wayne line at the time, The S-1 was a total disaster. Slippery, and a real B!tch on curves. The T-1's were not any better.The T-1 would slip like hell starting a train. It was standard operating procedure to assign a pusher to get a T-1 led train out of Columbus Station.   Best thing before the E-7's were the K-4's. Sure, dirty to work on, but sure-footed and could make the time. The Pennsy guys were a bit envious of the NYC Hudsons just to their north... It took two, sometimes three, K-4's to get a passenger train across the Alleghenies, while the "Central" whisked along with a single J-3.. At 90 mph.. 

 Now, John talked about running a T-1 from Crestline OH, To FT. Wayne IN hitting over 100 mph, but I can only imagine...   Look at that line today.  Weeds  and rotten ties. Ah, what a shame....... 

Todd 

 

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Posted by 3rd rail on Sunday, August 5, 2018 7:47 AM

WELL, While they were pretty to look at, I heard it fron the "Horses Mouth" (John Crosby) who was an engineer on the Ft.Wayne line at the time, The S-1 was a total disaster. Slippery, and a real female dog on curves. The T-1's were not any better.The T-1 would slip like hell starting a train.   Best thing before the E-7's were the K-4's. Sure, dirty to work on, but sure-footed and could make the time. The Pennsy guys were a bit envious of the NYC Hudsons just to their north... It took two, sometimes three, K-4's to get a passenger train across the Alleghenies, while the "Central" whisked along with a single J-3.. At 90 mph.. 

 

Todd 

 

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Posted by Jones1945 on Sunday, August 5, 2018 2:20 AM
My order of Loco Profile, 24 is arriving, I wish I can find some new detail in this 24-page booklet... In the past few years I put my focus on S1, T1 and Q2, seldom give too much attention to S1, anyway I think it is not possible to find another video footage of S1 in service (probably get thrown away like trash so many years ago) I can't even find the info of total mileage or average mileage per month of S1. But I found some interesting stuff of the Trail Blazer, I will share it on a new post, please stay tuned! Smile

_________________________________________________________________

IIRC both unique 3-axle trailing and the leading truck had independent suspension, consists of coil and leaf springs. The same type of trucks was used on S2 which make both engines had an impressive and unique look, they ensured good ride quality too.

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Posted by Jones1945 on Friday, August 3, 2018 2:26 PM
S1 1941
(Ron Ziel Collection, click to enlarge)

Imagine the air current created at that front shrouding which covered the coupler, when the engine speeding at over 100 mph. The front coupler cover was lifted up during her entire (except the first few months) service life from full-skirted period to de-skirted period, probably not only for better accessibility but also to dredge air stream. Another possibility was to provide better cooling for both Worthington 7-SA water pump under the streamline shrouding.
 
Photographic evidence showing that the front coupler cover on K4s #3768 seldom lifted up, probably because it was officially tested in a wind tunnel many times and it was partially de-skirted not long after she was put in service. However, I never heard or seen any info or pic about S1 or even T1 subjected to wind tunnel test. T1's front end has an improved design which was a Radiator Grille look-alike feature and three (supposed to be four) portholes to dredge air stream and ensure better cooling for the Worthington water pump. I especially like the prototype’s front end, but the heads of PRR did not.
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Posted by Jones1945 on Wednesday, August 1, 2018 4:00 AM

M636C

......Allen's own description is similar but less colourful. He did mention that two cast iron rail chairs in the curves had fractured...

LMS Vice President Sir Ernest Lemon said, at the press lunch:

"Of course, gentlemen, you will realise that we shan't need to do this kind of thing on every trip of the "Coronation Scot"; we were coming in a little faster than we shall have to do in the ordinary course..."


It always amazes me that the weight of PRR S1 without the tender was 304 short tons, PRR T1 was 251 short tons while LMS The Coronation Class was only 121 short tons!


A 9 cars consist of LMS, The Coronation Scot was 317 tons (including Kitchen cars) with a maximum capacity of 166 passengers.

Nine P70KR coaches in the consists of PRR, the Trail Blazer was 657.45 short tons with maximum capacity of 504 passengers, assuming the twin diner car and the head end, P70GSR coach and POC70R coach-observation had the same weight as the P70KR, the total weight and maximum capacity of the Trail Blazer (Pre-war version) consists was 1022 short tons and at least 588 passengers!

Average tonnage/passenger ratio of the above-named trains was 1.91(LMS) and 1.74(PRR) respectively. I used to have a false impression that passenger coaches in the State were built unnecessary heavy compared to UK's, but now I changed my mind.

Anyway, not all of the named train of PRR were all coaches train like the Trail Blazer, full Pullman sleeper train like the General and the Broadway Limited had much lower capacity, not to mention the pathetic ridership of the latter during the pre-war period......

LMS and PRR streanliner
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Posted by Jones1945 on Wednesday, August 1, 2018 2:30 AM

M636C

To revert to the original request, here are a couple of references:

Loco Profile 24 "Pennsylvania Duplexii" by Brian Reed Profile Publications Windsor UK, 1972.  Brian Reed was a locomotive design engineer with the North British Llocomotive Company.

"Rekord Lokomotiven" by Wilhelm Reuter, Motorbuch Verlag Stuttgart 1978 pp 303 to 315, chapter title "The Big Engine".

Peter

Thank you very much, Peter. Those are some publishment form 70s, I wonder if it is still possible for me to find them. I really want to read them, If our forum members own these publishment and willing to share with me, please kindly pm me! Thank you very much!! 

(Edit: I found a copy on the web of Loco Profile 24, but I am not sure if full name of  "Rekord Lokomotiven" by Wilhelm Reuter = "Rekord Lokomotiven - Die schnellesten der Schiene 1848-1950", I can found plenty of them on amazon but I can't read German...... Beer

Book

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Posted by Jones1945 on Wednesday, August 1, 2018 2:09 AM

 

Overmod
Meanwhile, the original Baldwin design provided for the T1 'thought' that all the drivers in both engines should be equalized together, which required some cleverness to get past the cylinder block for the rear engine.  Their solution was the long pivoted beam on the prototypes.
Thank you very much, Overmod. I remember S1 also had the same long pivoted beam between two set of drivers, and she was designed by Baldwin, Alco and Lima Locomotive Works under a joint contract, so I assume that using a long pivoted beam (which actually looks like a pair of huge reversed leaf springs) was a consensus between them, even though it turned out to be a unnecessary structure of the duplex design. Unfortunately we have no detailed documents or records about the progress of the making of S1 and all detailed record of the ideas shared between BLW, Alco, Lima as well as PRR, if not, it would be an interesting read!

(A "concept car" under construction in 1938 Stick out tongue Note the long pivoted beam under the rear cylinder)
S1 underconstruction

Overmod
One big advantage that came into postwar truck design was the use of  'silentbloc' rubber bushings at contact points and joints.  The French in particular made heavy use of this (and I think it was instrumental in achieving some of the contemporary high speeds reported for the equipment as early as the Fifties).  
 
Interesting! Speaking of the use of rubber on suspension, I remember it was adopted not only to train but also tram(streetcar) truck in the UK around late 40 to 50s, some of the tram truck design use rubber to replace the original leaf spring on the primary suspension, it reduced noise and ensured a smoother ride at low speed. If you want to know how the ride quality is, you could go to Hong Kong, their tram still using the original tram truck from the mid-40s.
(pre-war tram truck with its primary supension modified from using leaf spring to rubber)

Pre war tram truck
 
Overmod
What's the source for the streamlined-duplex 'cut' you provided?  That looks like something a British enthusiast would provide for a C1a using an auxiliary and perhaps corridor tender instead of track pans; we made very little use of that kind of deep angle cab even with vestibule, and the NYC cabs that had vestibules (the Niagara and A2a Berk important examples) had them up near deck height.  Is there a story associated with the picture, or more explanation of its origins?
 
It is a collection I found at the online archive of the Museum of Pennsylvania (they allow direct sharing of their online collections), the description is very simple. “1946, Proposed Streamliner for New York Central, Baldwin negatives” They do have two more drawing of it (show in pic below) with the name and signature of the designer or artist. I guess it was Baldwin's proposal of their direct-drive steam turbine engine (PRR S2 6200) for New York Central in 1946 to replace their Dreyfuss Super Hudson, the design of it reminds me of Otto Kuhler ‘s style. Unfortunately, the direct-drive steam turbine designs probably needed much more time to make it work to fulfill the State’s operating environment and requirement. On the other hand, streamlining steam locomotive is no longer a fancy thing after the war, NYC didn’t streamline their Niagara which would be adding unnecessary weight and wasting manpower for their fleet. Even PRR removed the streamlined shaurding of their 5 K4s like what NYC did to their Dreyfuss Hudsons and modified the front end of T1, completely changed its stylish looks.

 

Baldwin turbine proposal

 

 
 

BLW turbine proposal

 

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Posted by M636C on Wednesday, August 1, 2018 1:05 AM

I have more information regarding the 1937 test run of the Coronation Scot and its description mentioned by Overmod.

There are three separate descriptions of the entry to Crewe in Cecil J Allen's "British Pacific Locomotives" from Ian Allen in 1962. My first edition has the price "65 shillings" pencilled in the back. The 1937 run is covered on pages 137 to 139.

R.A.Riddles, later credited with the design of the BR Standard locomotives, was riding the locomotive.

Part of his description reads:

"Spectators from Crewe coming into view along the lineside; and the train still hurtling at 114 miles an hour. On went the brakes, off the regulator but on we sailed, flames streaming from the tortured brake blocks....   We were still doing 60 to 70 miles an hour when we spotted the platform signal. The crockery in the dining car crashed. Down we came to 52 mph through the curve, with the engine riding like the great lady she is. There wasn't a thing we could do but hold on and let her take it. And take it she did; past a sea of pallid faces on the platform we ground to a dead stand, safe and sound and still on the rails."

Allen's own description is similar but less colourful. He did mention that two cast iron rail chairs in the curves had fractured...

LMS Vice President Sir Ernest Lemon said, at the press lunch:

"Of course, gentlemen, you will realise that we shan't need to do this kind of thing on every trip of the "Coronation Scot"; we were coming in a little faster than we shall have to do in the ordinary course..."

Peter

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Posted by M636C on Tuesday, July 31, 2018 8:58 AM

Miningman

Well thank you for that erikem. Wow that's some kind of twisted up thinking on the government's part.

 
 
An example of twisted government thinking...
 
In 1986, the Australian Government introduced a "Fringe Benefits Tax". So if a company provided a car to an executive, his tax was increased by the nominal extra income that would have been paiid for him to buy and run the car.
 
Mc Donnell Douglas employed senior engineers in Australia at that time to assist in the local assembly of F/A 18  fighter aircraft for the Royal Australian Air Force. These people were paid their USA salaries, but Australian taxes were higher than those in the USA. So McDonnell Douglas paid the difference between the USA and Australian taxes. This paying of tax of course was a fringe benefit, so the Australian Government increased the tax paid by the engineers to compensate. This was paid by McDonnell Douglas. But it was an allowable cost of operation, so Mc Donnell Douglas were able to charge the total extra tax, plus 20%, to the Royal Australian Air Force, who ended up paying 141% of the tax differential for the engineers concerned.
 
I understand that Canada is buying the best of the remaining Australian F/A-18s to replace older Canadian aircraft of the same type. So if you see one, remember them as an example of government taxation gone crazy...
 
Peter
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Posted by M636C on Tuesday, July 31, 2018 8:12 AM

To revert to the original request, here are a couple of references:

Loco Profile 24 "Pennsylvania Duplexii" by Brian Reed Profile Publications Windsor UK, 1972.  Brian Reed was a locomotive design engineer with the North British Llocomotive Company.

"Rekord Lokomotiven" by Wilhelm Reuter, Motorbuch Verlag Stuttgart 1978 pp 303 to 315, chapter title "The Big Engine".

Peter

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Posted by Overmod on Tuesday, July 31, 2018 7:57 AM

... could you specific the detail of the ghastly unloading problem created by the long equalizing beam between the engines? I tired to search “steam engine unloading problem” on the web but it seems I found the wrong thing. I know the equalizing beam between the 2nd set of and the 3rd set of driver was removed from the production batch, but I don’t know about how a booster plus the equalizing beam affected the performance of 6111.

The two are really separate issues; I only mentioned them together in the context of problems affecting slipping in the evolution of the T1 design.

Remember that the T1 started with a somewhat ridiculously high FA, and was subsequently dialed even higher by the equalization changes; all this while the N&W J stayed ridiculously low.  In other words PRR and Baldwin recognized there would be a price for short-wheelbase duplexing, and expected that the increase in nominal wheel load on driver groups would address it -- the physics did not match their expectations, and one of the things the T1 Trust modeling will find out is the extent of that.

The purpose of a booster on a locomotive of this kind can be thought of as providing an 'additional coupled axle' that at low speed can use the boiler-generated steam efficiently where the main engine(s) can't.  They convert a Hudson briefly into a Mountain where starting a relatively long, heavy train is concerned, but when disengaged have no real effect on high-speed running (there is additional mass in the trailing truck, and some addition of unsprung mass on the rear trailing axle, but no unbalanced force in any plane from rotation, as there is with 'auxiliary engines' with rods).

Unsurprisingly, the NYC espoused the things, and perhaps also unsurprisingly PRR found reasons not to support anything the 'green team' was connected with.  But as Staufer noted, by the time the Niagara design came to fruition there was no booster, and he noted famously that it was needed 'about as much as a Christmas tree sticking out of the stack' as far as 'starting any load it could pull' was concerned.

The issue at hand is different: whether the additional smooth and gear-enhanced traction provided back at a trailing truck would solve or at least ameliorate the low-speed slipping issues with four-coupled duplexes starting a train over typical yard trackage, or accelerating with short stroke to the 35mph or so where the T1's began to produce real acceleration.  This would seem an ideal use even for something as simple as a Franklin E-2, but there's also a degree of 'where's my big savings?' both in first cost and maintenance if the booster only provides "equivalent" slip performance to a comparable 4-8-4.  (And if there were problems getting PRR to use front-end throttles and poppet gear effectively, imagine the fun with warming up, engaging, and disengaging boosters with no cutoff adjustment...)

Meanwhile, the original Baldwin design provided for the T1 'thought' that all the drivers in both engines should be equalized together, which required some cleverness to get past the cylinder block for the rear engine.  Their solution was the long pivoted beam on the prototypes.  One effect of this was pronounced unloading of the forward engine under any particular load.  Analysis of the suspension revealed that (no particular surprise) it was better to divide the suspension in the middle of the 'driver wheelbase' and tie off the equalization with helical springs and snubbing (which is choosing the spring rates so the various resonance frequencies are highly out of phase and the system as a whole tends to self-damp - this was a design principle on the GG1s but was later removed).  By 1947 all this had been repeatedly refined (there are many noted drawing revisions on the equalization by then!) and things had been perfected about as far as they could be without actual damping via shock absorption.

One big advantage that came into postwar truck design was the use of  'silentbloc' rubber bushings at contact points and joints.  The French in particular made heavy use of this (and I think it was instrumental in achieving some of the contemporary high speeds reported for the equipment as early as the Fifties).  If you look at the two truck designs you provide, note the radius rods and shock absorbers required especially for outside-swing-hanger designs; I believe John White has a section on proper postwar design in The American Passenger Car (vol.2).  More modern designs have much more emphasis on low unsprung mass and controlled degrees of freedom, but still require controlled damping of shocks and other running forces.

What's the source for the streamlined-duplex 'cut' you provided?  That looks like something a British enthusiast would provide for a C1a using an auxiliary and perhaps corridor tender instead of track pans; we made very little use of that kind of deep angle cab even with vestibule, and the NYC cabs that had vestibules (the Niagara and A2a Berk important examples) had them up near deck height.  Is there a story associated with the picture, or more explanation of its origins?

By the way, if one of the unofficial goal to develop T1 was to outperform Diesel like the NYC 
Niagara 4-8-4 which successfully achieved, using a booster would at least increase the average annual maintained cost and average annual fuel cost as well.[/quote]

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Posted by Jones1945 on Tuesday, July 31, 2018 2:36 AM

M636C

but post war trains had coil secondary springs with some form of damping added.

 

Post war train truck in US and UK,
Top: Commonwealth bogie (UK), Bottom: GSC 41-N-11 Passenger Truck (US)

Post war train truck

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Posted by Jones1945 on Tuesday, July 31, 2018 1:51 AM

M636C

It is generally agreed that the PRR S1 and UPRR "Big Boy" are generally the same sizes overall, despite the UP locomotive having twice as many coupled axles.

There is a table comparing some of the gigantic steam locomotives on steamlocomotive.com, the Grate Area, Evaporative Heating Surface, Superheater Heating Surface of S1 were smaller but very close to the "Big Boy", S1 only "beat" "Big Boy" by its tender weight, overall wheelbase, driver diameter and drawbar horsepower.

If “Maximum Axle Weight" on that table means the maximum Adhesive weight of one set of the driver, S1 was 73,800 lb, Big Boy was 67,800 lb. (Assume the figures provided are all accurate.)

I have seen an official movie by Union Pacific on YouTube which shown a Big Boy starting with wheel slipping on its rear set drivers, but once it starts moving, there was no problem. Smile
 
 
(Something I made when I feel bored Laugh )
Compare the size
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Posted by Jones1945 on Tuesday, July 31, 2018 1:02 AM

Miningman

Well thank you for that erikem. Wow that's some kind of twisted up thinking on the government's part.

If that was the best a government can do to a company which contributed so much to win the war, that was really messed up.

By the way, I wish people won't forget that she helped to win the war too: Cool S1 Trail Blazer

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Posted by Jones1945 on Tuesday, July 31, 2018 12:48 AM
Overmod
 
The spec for the T1 was dialed back to 880 tons at 100mph, a far more reasonable number for a locomotive with four-coupled engines especially in light of the lack of boosters for starting (you will remember that one of the prototype T1s was built with a booster, but had it removed in spite of the ghastly unloading problem created by the long equalizing beam between the engines, which was thankfully purged from the production suspension). 


I didn’t know that the booster was removed from 6111, could you specify the detail of the ghastly unloading problem created by the long equalizing beam between the engines? I tried to search “steam engine unloading problem” on the web but it seems I found the wrong thing. I know the equalizing beam between the 2nd set of and the 3rd set of the driver was removed from the production batch, but I don’t know about how a booster plus the equalizing beam affected the performance of 6111.

By the way, if one of the unofficial goals to develop T1 was to outperform Diesel like the NYC 
Niagara 4-8-4 which successfully achieved, using a booster would at least increase the average annual maintained cost and average annual fuel cost as well.       

V1


Miningman

Interesting thread with many branch lines!

If you recieved a whopping 17.6% hourly pay increase on top of a banner year of hours worked that even beat your last extremely profitable banner year and revenues exceeded expense, but you lost all the money and dipped into last years, then I can only conclude you went to the Casino ... a lot!  

It has been my understanding that Pennsy had a sort of military structure, no one at each lower level would dream of questioning those at the next level. I think this makes it easier for secrets and info withheld level to level. 



I bet 70 years ago when the concept of transparency and Media's supervision were not a daily thing, it was a completely different world compared to nowadays. (recommended thread: Jim Crow laws & railroads ). The military structure thing you mentioned in Pennsy makes it more difficult to find the truth today. If the Head of PRR (or other Class I railroads) did cheating or other shady things, I believe it is a mission impossible to reveal the truth without professional investigation, but many people involved had already passed away, not many railway enthusiasts have that amount of resource and time to find the truth. But I think it is a good start to at least raising the question. 

 
NYC proposed turbine
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Posted by Miningman on Monday, July 30, 2018 11:55 PM

Well thank you for that erikem. Wow that's some kind of twisted up thinking on the government's part.

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Posted by erikem on Monday, July 30, 2018 11:12 PM

Something to add about PRR's financial status in 1946...

IIRC, Paul North posted some PRR ad's from the late WW2 time frame about having to defer maintenance on their track to to prioritizing wartime traffic over maintenance. At the same time the federal government forced the PRR to declare the "savings" from not maintaining their track and then taxing that as income, which was then subject to the high wartime tax rates.

 

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Posted by M636C on Monday, July 30, 2018 9:44 PM

It is generally agreed that the PRR S1 and UPRR "Big Boy" are generally the same size overall, despite the UP locomotive having twice as many coupled axles.

Looking at the boiler barrel as something to base a comparison upon, the dimensions were:

S1 100" diameter by 21' 11" long

4000  106" diameter by 22' long

So unsurprisingly, the 4000 has a bigger boiler, but not significantly longer.

I'll have to think about the fireboxes since the arrangements are so different...

Peter

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Posted by M636C on Monday, July 30, 2018 7:20 PM

Interesting! I guess Gresley Bogie and PRR 2D P5 truck both doesn’t have shock absorber, am I right?

As I said earlier, both these designs had full elliptical leaf springs for the secondary suspension. These are the sort of leaf springs seen on the British LMS three axle bogie above the axleboxes, but combined as an inverted set pivoted to an upright set at each end of the leaves.

A feature of these springs is that the leaves move relative to eachother as the spring compresses or expands and this provides a built in damping that avoids oscillation.

At the time these trucks were designed, automotive style shock absorbers were not generally available, and automotive shock absorbers of suitable capacity only arrived in the 1950s.

If you look at USA streamliners, most prewar trains had full elliptical secondary springing, but post war trains had coil secondary springs with some form of damping added.

Peter

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Posted by Backshop on Monday, July 30, 2018 4:13 PM

Although some here have lamented the PRR for not preserving the S1, they actually did a decent job of preserving examples of their better known, bread and butter steam locomotives.

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Posted by Miningman on Monday, July 30, 2018 3:05 PM

Interesting thread with many branch lines! 

Anyone have any thoughts on how record setting freight and passenger transport translates into a loss when the year previous ( which was surpassed) shows a $49 million profit ...aaannnnd not only that but they enjoyed their recieved 17.6% increase in freight rates! 

Everything in the article seems to conflict. 

If you recieved a whopping 17.6% hourly pay increase on top of a banner year of hours worked that even beat your last extremely profitable banner year and revenues exceeded expense, but you lost all the money and dipped into last years, then I can only conclude you went to the Casino ... a lot!  

It has been my understanding that Pennsy had a sort of military structure, no one at each lower level would dream of questioning those at the next level. I think this makes it easier for secrets and info withheld level to level. 

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Posted by Overmod on Monday, July 30, 2018 11:24 AM

The 1943 proposal is likely a version of the infamous 'Triplex' which led to so much controversy between Carleton Steins and Raymond Loewy.  This is amusingly associated with the secret crash development program at Baldwin to produce the C&O M1 turbines 'outside' Steins' patents before PRR made turbines of its own ... there is loving, if potentially highly one-sided documentation of this in some of H.T. Cover's correspondence at the Hagley.  Some of the specific points of failure in the M1 design are more comprehensible when you know how they came about...

The spec for the T1 was dialed back to 880 tons at 100mph, a far more reasonable number for a locomotive with four-coupled engines especially in light of the lack of boosters for starting (you will remember that one of the prototype T1s was built with a booster, but had it removed in spite of the ghastly unloading problem created by the long equalizing beam between the engines, which was thankfully purged from the production suspension).  This is just about platform limit length of high-speed lightweight coaches for something like a Trail Blazer.  There is a certain optimism in designing Pullman trains for 100mph or faster operation over much of PRR where a considerable amount of high speed would involve projection out of one's berth, a consideration that factors amusingly into some of the anecdotes about high-speed running with the T1s.

It's not that Jawn was "too big", it was that he lacked meaningful horsepower for his size, and that characteristics of his electrical transmission made some of Baldwin's claims (the 65mph speed in particular) little better than ill-qualified lies.  Something burned out all those motors in no more than three years of testing, and trust me, it's hard to kill a hexapole even intentionally.

Note that a steam-turbine electric today requires a practical continuous horsepower of 8800 or greater just to remain competitive with conventional diesel power, even as it combines all the inefficiencies of mobile Rankine-cycle with water as the working fluid with electrical conversion and drive using truck-mounted motors.  It's possible there will be niches for such a thing; I am helping develop them.  But it's not very effective as a one-for-one replacement for a class A locomotive, or a properly improved Y-class either.

Boeing as you may know was involved heavily in transit car manufacture at one point (out of the Vertol helicopter plant in suburban Philadelphia).  I toured the plant as the first LRVs were coming off the line, and had great hopes for how the future would be.  Likewise United Aircraft (which was Sikorski) voluntarily perfected Allan Cripe's train as a showcase for PT6 turboshafts and then made a reasonable show of promoting it -- the 1967 proposal to NYC with detailed timing calculations made by computer is a dramatic positive example.  Of course Bombardier the snowmobile company became involved in aircraft production as well as diversifying into high-speed rail production, but that's not really the same.  The real problem is that, as for TGV with LGV, new routes optimized for very high speed are required to make true HSR practical.  Where that's not the case, it's far better to build to 110mph or 125mph specs, where the costs are not yet ridiculous or weight-saving quite so dramatically required, as in Britain where the HSTs were successful but the APTs (for a nominal top-end advantage of no more than about 25mph) were certainly not. 

And as done to death on various Trains fora, there are comparatively few services outside identifiable (and fundable) corridor services where 125mph service enhancements will pay their way.

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Posted by Jones1945 on Monday, July 30, 2018 10:24 AM

Overmod
In parallel, the evolution of the V1 into what became Jawn Henry is an interesting and valuable thing to observe.  The 4-8-0+4-8-0 became a span-bolstered C-C+C-C, which turned out to roast a set of hexapole motors beyond reasonable repair in just a few years of testing.  How much of that was attributable to drop damage in the main generators and how much of that was overloading may never be thoroughly known.

When I was much younger, I want to own a model of C&O Chessie. I admit I am obsessed with big machines.Smile, Wink & Grin

 V1, or Jawn Henry both have at least one thing in common, they are too big! Jawn Henry was even bigger than S1. I can understand that S1 was *probably built for the 39 World Fair to represent America (without PRR's stockholder's approval), so it was unnecessarily massive, heavy and *expensive.

Jawn Henry was not built to show off, but Baldwin didn’t or maybe not creative enough to design a practicable body which can house so many things inside one locomotive. In page 76 of the Book “Black Gold - Black Diamonds: The Pennsylvania Railroad & Dieselization” Vol 1, There is a drawing showing a proposed “pulverized coal burning, high-pressure steam, condensing turboelectric locomotive” of PRR from 1943, more than 10 years before Jawn Henry was built. The layout is similar to Union Pacific GTELs, a 3 unit set, which is much more practicable at least on the paper. It seems that building a reciprocating steam locomotive or diesel switcher was what Baldwin only good at. Not going to beat the dead horse today anyway, maybe tomorrow. Smile, Wink & Grin
 
Overmod
 the problem being that few if any people designing then seemed to understand the profound split in costs and infrastructure involved in operation to 125mph as opposed to 150 or higher.  The French figured this out, right down to the required power infrastructure, and so they've gone from success to success and have pervasive true high-speed rail

I do have an impression that the Federal Government "murdered" most of the railroads on purpose, but I will keep being open-minded and learning. Imagine Baldwin, Alco and Lima still exist today and making high-speed trains and railway stuff, can they contribute as much as The Boeing? Like China, a country can’t make bank by making Civil Aviation Aircrafts, tried to export their HSR to other developing countries for years, but turn out they run up against the wall everywhere. Developed countries can make high-speed rail by themselves, development of aerospace and automobile, making bank by exporting them is the most beneficial thing to the State. But I think the fallen flags can't blame the Federal Government for everything, many of them have so many issues like poor management and restless investments, not to mention possible corruption.
 
Overmod
look at the 'mission' difference between the S1 and T1 spec, and tell me realistically what sort of passenger consist needs to weigh 1000t in a single train that fits real-world platforms, especially from the Forties on as demand for multiple sections starts falling away. 

 
I am afraid only PRR can answer you this question my friend since the "hauling a 1,000-ton passenger train at 100 MPH” requirement of S1 was from PRR, a company which running his business for more than 90 years in 1938! Assume a post-war lightweight Pullman sleeper is 48 tons, a 1000 tons consists would have 20 cars, if it was a pre-war H/W Pullman consists, it would be 15-16 cars, the latter was quite common (including all the head end) during the Wartime traffic to be honest. Maybe PRR was too optimistic on the ridership or maybe S1 was just a showpiece for the 39 World Fair, this “requirement” or goal was just another talking point created by PRR to entertain the visitor. Don’t get me wrong, I love T1 too, especially the prototypes, I collected tons of pics of T1, S1, as well as S2, Q1, and Q2. Smile, Wink & Grin
 
The difference of weight and length of passenger car between the US and Europe is another topic I wish to learn more, maybe next thread. 

(IIRC there was another version of the story about this 4-6-4-6 drawing of "Q1", I will try to find the detail)
 4-6-4-6
Overmod
If you want a reasonable starting point for a PRR "next-generation M1" 4-8-4, I would advocate starting with a "late" C&NW zeppelin H, with or without duplexing, and put a double Belpaire boiler on it


Noted with thanks! Overmod. By the way, I found another old thread from this forum, the title was "Duplex Steam Locomotive / Steam discussion", there are so many things to read and learn, thank you once again for everyone's generous sharing! I feel like I am back to school again. (in a good way)Bow

PRR T1 6110 (1942- 1992 1952) 
T1 6111
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Posted by Overmod on Monday, July 30, 2018 5:53 AM

As to the 'follow-ons' for the electric district, the answer is actually historical (and verifiable from a variety of sources) -- rectifier/Ignitron locomotives using diesel-style bogies with relatively low wheels and independent-axle traction motor drive (with DC, not universal, motors).  This was clear on PRR by the time of the 'experimental' classes ordered in the early Fifties, and culminating in the vacuum-cleaner E44s ordered in the early Sixties.  All these predominantly for freight, of course; passenger needs were covered by the wartime GG1s (in what might be considered a reprise of too many K4s in the Twenties) so no New Haven 'Jet' analogues, but that's what you would have seen had the passenger electrification been taken up at a reasonable point after the War.

In parallel, the evolution of the V1 into what became Jawn Henry is an interesting and valuable thing to observe.  The 4-8-0+4-8-0 became a span-bolstered C-C+C-C, which turned out to roast a set of hexapole motors beyond reasonable repair in just a few years of testing.  How much of that was attributable to drop damage in the main generators and how much of that was overloading may never be thoroughly known.

Anyway, as I mentioned before, the Federal government didn’t want to see the development of the nation’s Aerospace industry slowed down by High speed rail, thus we have what we got today.

 
The truth is just the opposite; see the UMTA as part of the 'guns and butter' in the Johnson administration, and consider that any modern high-speed passenger enhancements by the 1960s would require extensive Federal subsidy no matter how 'proprietary' they were (think how many railroads would invest in Metroliners...)  This is also the era of Bertin and various kinds of hovertrain, and of the thought that supersonic transport was the next great service development in the Jet Age, so what we now acknowledge to be wacky technologies were fostered right along with those for steel rails -- the problem being that few if any people designing then seemed to understand the profound split in costs and infrastructure involved in operation to 125mph as opposed to 150 or higher.  The French figured this out, right down to the required power infrastructure, and so they've gone from success to success and have pervasive true high-speed rail, while American development couldn't figure out how to put the necessary motor power density in Pioneer trucks and to this day has the porky Acela as its excuse.
 
Were priorities to change ... or better lobbying to be organized ... this could change.  But not within the RPO-mandated buff and draft requirements.
 
The objection to the S1 was and is that it's too damn big for any of the use you can get out of it.  That was implicitly recognized in the T1 development, of course; you should note that a T1 isn't even a very large 4-8-4 to be making 6400hp, as would have been a C1a.  As with the S2, you get rid of the six-wheel trucks and the heavy architecture, and 'get out the tinsnips' as Al Staufer put it, and not incidentally develop lightweight and capable rolling stock for meaningful consist size -- look at the 'mission' difference between the S1 and T1 spec, and tell me realistically what sort of passenger consist needs to weigh 1000t in a single train that fits real-world platforms, especially from the Forties on as demand for multiple sections starts falling away.  Keep in mind that this is not the Lima use of three trailing-truck axles to accommodate perceived-better circulation and chambering and the sometimes-ridiculous mass increases that conventional enlargement of that area particularly with Nicholson syphons provides.  Even the PRR 'enlarged Q1' drawing has the wrong design of trailing truck, as though it didn't matter geometrically where the axles and the pivot were located for reasonable engineering.
 
If you want a reasonable starting point for a PRR "next-generation M1" 4-8-4, I would advocate starting with a "late" C&NW zeppelin H, with or without duplexing, and put a double Belpaire boiler on it (the 76" drivers being acknowledged as the highest that would fit the PRR clearance diagram with a rightsized version of that chamber, and plenty high enough for balanced speed with Timken rods).  Use arch-tube circulators and not those silly syphons.  I suspect there was plenty of evidence as to what circulation methods worked and which didn't in the records of various railroad companies trying different arrangements ... most of which was probably lost without much trace as dieselization progressed.  Fortunately it is not rocket science to figure out expedient methods of maximizing steam generation within packaging and even weight requirements; one reason I support Snyder preheaters and Cunningham circulators so strongly is that they provide meaningful thermodynamic advantage for comparatively little structure and operational complexity.
 
Yes, I'd keep type B (or even "C") and use the three-poppet arrangement used on ATSF 3752 even if there would be parts and service commonalty with 8-valve T1s.  To retain piston valves you're talking proportional improvement over M1a valves, probably all the way to 15", and special arrangements to drive these with lightweight means would need to be checked into (see some of the late French experimentation, notably on the last de Caso Hudsons, for interesting ideas).  One alternative would be to use the divided steam path idea of Franklin gear with a pair of separately-driven piston valves (one for admission and one for exhaust and drifting bypass) but that's a lot of structure and weight, and substantial maintenance issues, for the advantages gained

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