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Pennsylvania T-1 4-4-4-4 passenger service

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Pennsylvania T-1 4-4-4-4 passenger service
Posted by dumbasapost on Saturday, October 15, 2016 10:41 AM

Hi all,

Recently I've become interested in the short-lived Pennsylvania T-1.  I've been trying to track down information regarding its passenger service, but I seem to be spinning my wheels so I thought I would turn to you guys for help.

What trains did the T-1 pull? Did it ever pull the Broadway Limited?  What would a prototypical consist look like for a T-1 in the early 1950's?

Many thanks!

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Posted by BRAKIE on Saturday, October 15, 2016 11:28 AM

The majority of the T-1s was used between Crestline(Oh) and Ft.Wayne(Ind)..In fact a square building next to the roundhouse was used for the Ts.

The reason I said the majority was used on the Ft.Wayne line is because I seen photos of Ts in Columbus(Oh).

Larry

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Posted by tomikawaTT on Saturday, October 15, 2016 2:44 PM

According to the CrestlinePRR website, when new the T1s were assigned to the Pennsy's premier trains, which presumably included the Broadway Limited.  However, they were the first locos to be supplanted when the PRR dieselized, dropping to mail train service before joining the parade to the scrap line.

The T1 was an unfortunate design that suffered from a myriad of faults that killed it before there was time to find and install corrections.  PRR would have been well advised to redesign the N&W J with higher drivers.  Note that the PRR had much better luck with conventional 2-cylinder 2-10-4s than with the Q-duplexes.  In railroading, KISS rules - a fact that inevitably shows up on the bottom line.

Chuck (Modeling Central Japan in September, 196 - sans duplexes)

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Posted by 7j43k on Saturday, October 15, 2016 3:33 PM

My belief is that the T's were excellent locomotives.

They, perhaps, demanded more of their operating and maintenance crews than they could deliver.

 

Ed

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Posted by Firelock76 on Saturday, October 15, 2016 3:53 PM

For a superb, myth-busting telling of the T-1 story get yourself a copy of the Classic Trains magazine special issue "Steam Glory 3."  There's an article in it by David R. Stevenson that tells the whole story.

In a nutshell, once the initial teething troubles inherent in a new design were ironed out, and crews were properly trained the T-1's worked just fine.  What really killed them was the Pennsy's decision in 1946 to dieselize all the long-distance passenger trains hauled by steam, so the T-1's were out of a job just as the job started!

A previous poster was right, though.  PRR could have saved themselves an awful lot of trouble if they'd bought Class J's from the N&W earlier on.  Why didn't they?  Personally I think it was ego, the "Standard Railroad of the World" couldn't admit those "hillbillys" down in Roanoke were better at steam locomotive design than they were!

Anyway, go to the Classic Trains site, select "shop," then "special issues" and you'll find it.

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Posted by 7j43k on Saturday, October 15, 2016 5:10 PM

I agree that Pennsy was pretty sure it knew all there was to know about steam locomotive design.  And they knew a lot, for sure.

But NOBODY bought N&W J copies.  And PRR DID buy those 2-10-4 copies.  Perhaps N&W didn't care to build J's for the Pennsy. 

Maybe Pennsy should have gotten copies of GN's S-1's.  They had Belpaire fireboxes, after all.  And pretty small drivers, like the J's.

 

 

Ed

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Posted by gmpullman on Saturday, October 15, 2016 5:37 PM

PRR did test J No. 610 between December 4, 1944 through January 3, 1945 making 12 round trips in passenger service, including The Broadway, General, Admiral and Liberty Limiteds, plus two round trips in freight racking up 7,100 miles. Several stretches were made at over 100 MPH and at one point 610 was clocked at 111 MPH (70" drivers rotating at 533 RPM!)

A very interesting article about the test is in the V41, #4 issue of The Keystone.

Regards, Ed

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Posted by Firelock76 on Saturday, October 15, 2016 6:10 PM

Well, the PRR bought (and built) those C&O 2-10-4 copies because they HAD to, World War Two was raging, the Pennsy needed new freight power desperately, but the War Production Board wouldn't allow the PRR the time or resources to develop a new design of their own, they had to go with an existing model. As it was, that C&O design worked out just fine.

As to Class J's, keep in mind the PRR owned a majority interest in the N&W at the time, so they certainly were aware of what the Class J's were capable of, hence the mystery of why they didn't go that route.

Certainly no other railroad bought Class J's either, but remember this was a day and age when most major 'roads had their own ideas of what a locomotive should be.  It would take GM/EMD's "take it or leave it" attitude toward their diesels that would break that mindset.

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Posted by BRAKIE on Saturday, October 15, 2016 8:00 PM

7j43k

My belief is that the T's were excellent locomotives.

They, perhaps, demanded more of their operating and maintenance crews than they could deliver.

 

Ed

 

Ed,I read in books and magazines and heard stories the Ts would hit 100 mph West of Lima. The Ts sounded like good engine born in the wrong decade.

Sadly wasn't for WWII diesels would had started replacing steam earlier and there may not have been any Ts built.

Larry

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Posted by 7j43k on Saturday, October 15, 2016 8:20 PM

Larry,

In the Wikipedia article on the T1's, there's a claim by a guy who said the T1's had hit 140 MPH.  More than once.

I know that "claims by a guy" are REALLY open to question.  We do it here sometimes.

 

But.

 

 

Ed

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Posted by tomikawaTT on Saturday, October 15, 2016 10:35 PM

As for why other roads didn't buy N&W Js (or build their own) - the J was designed to be a HEAVY locomotive, which was no problem on the N&W but would have raised havoc on routes laid with 115 #/yd or lighter rail.

Reportedly the Pennsy was leery of the low drivers, which is why I suggested a redesign to 80 inch drivers (as well as a Belpaire firebox.)  The resulting R1 class would almost certainly have been a supurb locomotive.

Chuck (Modeling Central Japan in September, 1964 - track speed limit 43.5mph)

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Posted by 7j43k on Saturday, October 15, 2016 10:49 PM

tomikawaTT

As for why other roads didn't buy N&W Js (or build their own) - the J was designed to be a HEAVY locomotive, which was no problem on the N&W but would have raised havoc on routes laid with 115 #/yd or lighter rail.

Reportedly the Pennsy was leery of the low drivers, which is why I suggested a redesign to 80 inch drivers (as well as a Belpaire firebox.)  The resulting R1 class would almost certainly have been a supurb locomotive.

Chuck (Modeling Central Japan in September, 1964 - track speed limit 43.5mph)

 

 

So merging the GN's S-1 and S-2 would have been a great idea.  80" drivers and a Belpaire firebox.  Apparently, the GN declined to Belpaire the S-2 because of the added weight.  Maybe, I suppose.  But considering their previous "elite" passenger engine, the P-2, was also missing a Belpaire firebox, perhaps management was of the opinion that Belpaire fireboxes weren't appropriate for the high-class passenger engine.

Uh.  I would disagree.

 

Ed

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Posted by ACY Tom on Saturday, October 15, 2016 11:06 PM

PRR bought two experimental T1's from Baldwin in April and May of 1942 and put them into service on their first-line passenger trains. No more passenger power was bought until after the war.

The road made a half-hearted foray into diesel power with the purchase of their first passenger diesels, E7 AA set 5900-A and 5901-A, in September, 1945. These were assigned to the Harrisburg-Detroit segment of the Red Arrow. Most observers think PRR motive power officials thought of the E7's as a novelty, not to be taken seriously.

PRR's really heavy investment in T1's came in the form of 50 T1's from Baldwin and their own Altoona Shops November, 1945 through August, 1946, numbers 5500-5549. These were immediately assigned as first-line passenger power for the road's most important mainline passenger trains between Harrisburg in the East, and Chicago, St. Louis, and Cincinnati in the West.

When diesel efficiency and maintenance economics became too obvious to ignore in the late 1940's, PRR began buying passenger diesels from all four builders. By about 1950, the road had decided that they preferred EMD over the other builders. After that, PRR's passenger purchases were almost all E8A's, with a few FP's and SG hood units.

In 1950, the T1's were all still on the active passenger roster, but were mostly handling secondary trains and serving as protection power. In May of 1950, T1's were no longer running into Chicago, Cincinnati or St. Louis, but they were still assigned to all of the other Divisions of their original territory. The Keystone Crossings web site says at that time the 52 T1's were distributed like this:

Middle Division, Harrisburg - Altoona 19 engines

Pittsburgh Division, Altoona - Pittsburgh 5 engines

Eastern Ohio Div., Pittsburgh - Crestline  4 engines

Fort Wayne Div., Crestline - Fort Wayne  6 engines

Panhandle Div., Pittsburgh - Columbus  9 engines

Columbus Div., Columbus - Indianapolis  9 engines 

Most T1's were taken out of service in 1952-3, and the last ones were stricken from the roster in 1956.

They were outstanding locomotives, with incredible beauty, power, and speed. They could be slippery and temperamental, but they were superb when operated with the right "touch" in appropriate service on appropriately engineered track. Their downfall was maintenance. They didn't do too well on severe grades. 

If you want a bloody nose & perhaps to lose a few teeth, just start an argument about this among a few SPF's. I've said about enough to maybe get me in trouble, so I'll bow out now.

Tom

(edited, corrected, expanded)

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Posted by BRAKIE on Monday, October 17, 2016 7:36 AM

ACY
If you want a bloody nose & perhaps to lose a few teeth, just start an argument about this among a few SPF's.

Remains me of the proud P company men that hated the very idea of merging with the NYC-a long time rival.

Larry

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Posted by ACY Tom on Monday, October 17, 2016 8:12 AM

Top speed of a T1? 

That's anybody's guess. You may not be able to count that high.Big SmileWow

Tom

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Posted by JOHN BRUCE III on Monday, October 17, 2016 10:02 AM
One point that isn't made very often is that in the 1930s the PRR planned to increase train speeds across the board. The duplex drive was intended to allow this with reciprocatilng steam locos, which had a basic problem of requiring the rods to be counterbalanced, which damaged track and limited practical top speeds, since the balancing could never be perfect. The duplex drive reduced the weight of the rods to be counterbalanced. Diesel traction motors solved the problem by eliminating the problem, although the cost of dieselization put a permanent hold on any other PRR plans. Maintenance costs on the duplex locos in comparison with diesels took them out of the running pretty much as soon as the diesels arrived in quantity. The PRR in fact tried to sell the T1s to the N&W, but the J1 and T1 were designed for different service. The T1 was ideally designed for projected 100 mph passenger service, the J1 for 70 mph, which the N&W never meant to exceed.
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Posted by dumbasapost on Monday, October 17, 2016 10:27 AM
Thanks for all of the replies gentlemen. Lots of good information for me to move forward with!
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Posted by dti406 on Monday, October 17, 2016 11:42 AM

tomikawaTT

Reportedly the Pennsy was leery of the low drivers, which is why I suggested a redesign to 80 inch drivers (as well as a Belpaire firebox.)  The resulting R1 class would almost certainly have been a supurb locomotive.

Chuck (Modeling Central Japan in September, 1964 - track speed limit 43.5mph)

Would not have been an R1 Class, that was already taken by one of the PRR Experimental Electrics, would have been the R2 Class.

Rick Jesionowski

 

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Posted by ACY Tom on Monday, October 17, 2016 1:15 PM

During the period from 1944 to 1947, Lima did design work on a Double Belpaire 4-8-6, and that seems relevant here. PRR probably would have preferred 80" drivers over Lima's proposed 70"; but otherwise the Lima design was probably close to what a PRR 4-8-4 would have been. PRR made the decision to dieselize passenger service about the time Lima finalized its designs, so the project never went any further than the drawing board, plus a 1/6 full size model of the boiler, which is said to still exist at the National Museum of Transport, in St. Louis. No potential customer ever expressed any serious interest in Lima's 4-8-6. It simply came along too late.

If the 4-8-6 wheel arrangement had been adopted by PRR, they would probably have not used the R class. They would probably have used some other letter like U, V, etc. Class F would have also been a possibility, since that was the vacant class letter for 2-6-0's, which were all retired. FF1 electrics were retired as of 1940, and FF2 electrics were not in the picture because they weren't obtained until 1956.

Tom

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Posted by 7j43k on Monday, October 17, 2016 1:37 PM

If the point of a 6 wheel trailing truck on a 4-8-6 was to allow a larger firebox, I'll note that the T1 had a pretty small one.  Which would get me thinking they wouldn't have gone with a 6 wheel.

Now, NP apparently liked a large grate area for their, uh, inferior coal.  Seems THEY might have considered it.

Anyone else out there that had high speed running and a penchant for large grate areas???? 

 

Ed

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Posted by SouthPenn on Monday, October 17, 2016 9:07 PM

Looks like there might be a T1 in the future.

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Posted by ACY Tom on Monday, October 17, 2016 9:25 PM

When choosing a T1 model, it might be worthwhile to be aware of the detail differences. The first two engines, numbers 6110 and 6111, had sharper, more pointed prows than the fifty production models of 1945-46. They were all delivered with bulbous housings on the pilot deck, but that was changed by about mid-1948 to a design with stairs flanking a smaller rounded housing. Some sheet metal was cut away from the tender at this time to facilitate servicing. Both streamlining treatments have been offered in HO brass and by BLI. Most or all represent the fifty production models. I don't know whether anybody ever released a correct model that represented the pointed prow of 6110/6111. (Maybe Gem?). BLI has models of the fifty production models, both before and after revision of the streamlining. 

Which version you choose will depend upon your own aesthetic preferences and/or the era you model.

Tom

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Posted by RME on Friday, October 21, 2016 5:00 PM

JOHN BRUCE III
The T1 was ideally designed for projected 100 mph passenger service, the J1 for 70 mph, which the N&W never meant to exceed.

 Where railfans get some of this stuff, I'll never know.

Voyce Glaze clearly described that the J was intended to have a 100mph 'dash' capability (for making up time) and that the locomotive was therefore balanced for a speed safely above that.  (Hence the PRR testing the locomotive with impunity at speeds greater than 110mph, with valves being the 'point of failure' restricting achievement of higher speeds).

No double-Belpaire locomotive on PRR would have had "80" drivers"; there was only room in the clearance diagram for 76" (as documented at Lima) due to interference of the lower two 'lobes' of the chamber with the rear driver-pair flanges.  Of course the combination of lightweight rods and better balancing that revolutionized many older designs in the '30s would easily allow speeds well above 100mph with drivers that size, although Franklin type B (or "C", as planned for the 4-8-6 Lima intended to build) might have been needed to allow free running at very high cyclic rpm.

There were two kinds of 'slipping problem' with the T1s, the usual railfan one being the low-speed slips due to frogs, low joints, oil on the rail and the like, as seen in so many videos.  That was not the critical one.  Remember that the T1 was sized to pull the length of train commensurate with its higher horsepower (880 tons at 100mph) and those trains, at high speed in uncertain weather, could provoke high-speed slipping (which had to be corrected with the throttle and not the valve-gear control linkage, and this was relatively difficult because there was only one throttle valve for both engines, but easier than it might seem because the throttle was a proportional air servo and not a long jointed linkage against the variable and often heavy resistance of nominal 300psi steam). 

The thing that fixed the effective top speed of a T1 was neither boiler nor cylinder capacity.  It was likely (and I expect the T1 Trust modeling to show this fairly early) critical resonant frequencies in the suspension.  which if manifesting at any speed much above 120mph would produce the effect of very hard riding that could not be sustained until the locomotive power accelerated it through the resonant speed.  Several possibly apocryphal accounts describe this behavior between about 132-135mph, which I think represents a fairly hard limit.

(The "140mph" number is actually a little above that -- and it does not concern T1s.  It was Arnold Haas' number for the speed supposedly achieved by S1 6100 on the Trail Blazer in the postwar years (before the ICC restrictions kicked in after 1950).  Hass of course was infamous for overestimating of NYC steam (120+ regularly achieved by Niagaras, for instance) and the speed he gave (complete with decimal point) corresponds to an exact multiple of km/h (he was European).

 

 

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Posted by ACY Tom on Friday, October 21, 2016 7:46 PM

I suggested PRR would have preferred 80" drivers on the hypothetical Double Belpaire 4-8-6, but I agree that probably wasn't achievable due to the limited space under that Double Belpaire. The whole discussion is theoretical anyway since it never happened and never had any serious likelihood of happening. 

Tom

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Posted by RME on Friday, October 21, 2016 11:22 PM

ACY
The whole discussion is theoretical anyway since it never happened and never had any serious likelihood of happening.

You might be surprised.  Westinghouse had a clearly recognizable "4-8-4 version" of the S2 direct turbine in one of their promotional brochures of 1948...

Something to remember is that PRR actively researched a number of the issues with the T1, notably the breaking valves, and had fixes for them by 1948.  At that point the decision had effectively been made not to use the T1s as first-line passenger power, but there would have been no point in going to a heavier, slower eight-drivered passenger steam locomotive at that point.

What would have been used is probably the follow-on version of the V1 turbine that Loewy did the fancy passenger design (I believe in 1947) for.  This would have had the Bowes drive, perhaps to make higher 'passenger' gearing practical, and while I think the "9000hp" rating PRR tied onto the locomotive was ridiculous (look at the water rate alone that would have been required!) the design is even more optimized for 120+mph than the Centipede/Essl undercarriage.  (And, had the double Belpaire proven itself as a desirable chamber structure, the V1 chassis would have allowed it without loading-gage compromise of any kind.)

There's a reason PRR never went to a reciprocating 4-8-4 even though it's the logical 'next step up' from an M1, and they had the Niagara both at 75" and 79" for comparison.  (Meanwhile, NYC ran over 22 pages of study on the C-1a, so go figure...)  By the time there was a possibility of a non-divided drive (and non-turbine) passenger locomotive, the advantages of E and F units had been very well demonstrated, and the perceived and actual need for very high-speed performance on PRR's trains outside the electrified district had dropped to what reliable diesels could comfortably accommodate (with much less rigmarole).

Note that the Niagaras, commonly touted as among the most successful big steam locomotives built, outlasted the T1s by no more than half a decade.

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Posted by selector on Saturday, October 22, 2016 5:49 PM

7j43k

... And PRR DID buy those 2-10-4 copies.  Perhaps N&W didn't care to build J's for the Pennsy. 

...

 

 

Ed

 

The PRR did test a J Class, but burned a valve in it at high speed.  So, they would have had to redesign it for the speeds the Pennsy needed.

As for the C&O's T-1 2-10-4, they needed to get something off the shelf since the War Production Board would not permit new designs.  They realized the need for heftier haulers, tested the T-1, and decided it would do what they needed it to do.  It had a different pilot, the cast pilot, and different headlight position if I recall.

 

 

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Posted by selector on Saturday, October 22, 2016 5:55 PM

ACY

Top speed of a T1? 

That's anybody's guess. You may not be able to count that high.Big SmileWow

Tom

 

 

My guess would have been near 125-130 mph.  While it may have been adequately balanced, and even had a good steaming ability to go somewhat beyond that upper limit, the lubrication of the fast-moving piston and valving above it would have been the Achilles heal.  When the Pennsy tested an N&W J, they ran it so fast (near 100 mph if memory serves) that one of its valves ran out of lube and they had to shut down the event.  So much for 70" drivers.

This is NOT to deprecate the mighty J.  It was purpose-built, and did it's job with flare in addition to being highly adept.  Full props to the designers of that engine.

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Posted by ACY Tom on Saturday, October 22, 2016 6:48 PM

There is no question that a 70" drivered N&W J could and did operate in the 100 mph range when pushed; but normal operation called for more modest speeds in the 70 mph range. PRR wanted higher speeds in the Crestline-Chicago territory and probably would have gone for the tallest drivers practical.

As I said, it's all theoretical, since the final decision not to build a PRR 4-8-4 or 4-8-6 was made 70 years ago.

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Posted by RME on Sunday, October 23, 2016 3:44 AM

selector
My guess would have been near 125-130 mph. While it may have been adequately balanced, and even had a good steaming ability to go somewhat beyond that upper limit, the lubrication of the fast-moving piston and valving above it would have been the Achilles heel.

Kiddo, all the Tis were built with Franklin poppet valves for this reason, and any 'Achilles heel' issues involving improper spring or seat combinations causing broken valves were either fixed or addressed in principle (e.g. through better material or centrifugal casting) by 1948.   GThere is some evidence -- it cuts both ways -- that the type A valve gear, which allowed continuous cutoff without the wear issues of cam-shifting, but still oscillated with mass reversal, was better suited to practical high speed operation - we won't reqally know until the T1 Trust does the multiphysics modeling, and even then there are more compelling reasons to use rotary-cam (as in type B) with outside drive.

There are some steam-port configuration issues and even steam momentum effects (as on the Q2) that may come into play at very high speeds -- again, we won't really know until all the parameters are modeled.

When the Pennsy tested an N&W J, they ran it so fast (near 100 mph if memory serves) that one of its valves ran out of lube and they had to shut down the event. So much for 70" drivers.

The actual speed was above 110mph - there is some argument on exactly how much above 110, with individual mph being very significant for this design in this speed range; I think the 'right' answer is between 112-113 without having the dynamometer results or any of the review article material at hand.  If Dave Stephenson (feltonhill) reads this, he may care to comment as he probably knows this material better than anyone else.

The damage was likely due to consequences of excessive superheat rather than some 'inadequate lube problem' - what was observed was heat bluing of the valve, which indicated to me that some combination of expansion of the valve spool and deterioration of the oil tribology caused the observed seizure.  Again, this was the engine being run at the upper limit of its design balance, far in excess of where the mass flow through the superheater was expected - Ross Rowland and others can attest to what happens to superheat temperatures on these large modern engines when run at very high speeds for sustained periods.  It is likely that any "PRR J" used for high-speed service would have been equipped with poppet vaqlves, or have the valves and gear designed according to the principles used for the T1a conversion (which I will take up in a moment).

The N&W assessment of the T1 test results (in 1948, I think) has survived and been reported on repeatedly, including in the Trains Magazine forums.  The PRR assessment of the high-speed J testing has also survived (in the Hagley) and is interesting reading.  Specifically mentioned is that a 'higher wheel' was understood as necessary for PRR purpose (and would have been provided in any subsequent adaptation of a large 4-8-4.)  Meanwhile -- and again, I think Dave Stephenson will have definitive knowledge -- even with 70" drivers the J was outside PRR clearances for a number of key places, including the approach to Chicago, and this is one reason the high-speed testing didn't produce any "J orders" with higher wheels, as the modeling crayonistas seem to think is a mod as easy as switching the Niagara prototype from 75" to 79"

Much of the T1a design has been covered in sources like the Keystone, and there are also discussions of it (and the implied compromises) in the material at the Hagley.  One very specific understanding is that the high-speed efficiency falls off exactly in proportion to the "inprovement" noted by Franklin for the poppet-valve K4 testing; the locomotive was fine past the low 100mph range but would be substantially hampered in reaching even the 120mph range.  (I have seen the comparison for "DBHP at speed" as PRR plotted it for the T1 vs. T1a, but don't have a copy.)

The T1a conversion was in part an admission that the PRR of the late '40s was never going to be a railroad making much use of very-high-speed reciprocating steam, but was still very much in need of single locomotives that could do the job of doubleheaded K4s to run trains at doubleheaded-K4 speeds.  So an engine that reliably ran at 85mph with high speed to, say, 110mph was a perfectly good solution ... in fact, a good enough solution to warrant an expensive (and patented!) process to eliminate high-speed slipping and other maintenance woes associated with type A poppets by providing good piston valves and conventional valve gear.  (I find it interesting that PRR used Walschaerts rather than long-travel Baker here even though they had access to data for by far the best Baker designs in the business (and a fairly good idea of how Baker arrangements could fail at high speed!) through the N&W 'connection'.)

For anyone interested, the relevant material is all in the T1 Trust repository.

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Posted by ACY Tom on Sunday, October 23, 2016 11:02 AM

See the current RMC for one guy's take on a possible PRR 4-8-4. An improbable scenario, just for fun.

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