The concurrently running Thread here regarding the PRR T-1 ; seems to have gone into topics, more regarding time tables, and speeds between stations(?)
The title did spark memories from some time past. IIRC it was aboiut 2010(?) or so, when the topics of possibly building a 'new;' 4-4-4-4 type PRR T-1; and 'running' it (somewhere) ? It seemed to be a real "pie-in-the-sky" idea. Of Course, it was going to be 'expensive' ! Personally, I thought it was just a project for dreamers.
So, Here we are, some 10+ years down the road: It seems that not only have those 'fans' found some funding, but have advanced some of their condtruction of what will become of a NEW T-1 steam locomotive, of PRR Heritage...
See linked @ https://prrt1steamlocomotivetrust.org/
Pages of its' boiler , and also a pictograph of its completed working parts.
Searching Google; you can find several websites devoted to this project(*PRR T-1)
Possibly, some day, some will be able to witness a brand new PRR T-1 #5550 burnishing the rails, west out of Crestline,Oh. ?
It may be geographically west of Crestline but it sure won't be on the old PRR.
Closest you're likely to get to ex-PRR 'west of Crestline' would be Ohio Central on the old St. Louis line, and running there wouldn't be 'burnishing'.
The actual high-speed testing will be on the Fast Loop at TTCI in Pueblo. (That is what requires development of the instrumented wheelsets.)
Overmod Closest you're likely to get to ex-PRR 'west of Crestline' would be Ohio Central on the old St. Louis line, and running there wouldn't be 'burnishing'. The actual high-speed testing will be on the Fast Loop at TTCI in Pueblo. (That is what requires development of the instrumented wheelsets.)
When you say "Fast loop" I presume you mean the Railroad Test Track (RTT) with 50 minute curves and 6" superelevation, 100 mph balance speed, not the Facility for Accelerated Service Testing (FAST) track which typically runs at 40 mph as I recall.
I'd be interested to see it run on the Wheel-Rail Mechanism (WRM loop) track to measure how it handles perturbed track.
bogie_engineerWhen you say "Fast loop" I presume you mean the Railroad Test Track (RTT) with 50 minute curves and 6" superelevation, 100 mph balance speed, not the Facility for Accelerated Service Testing (FAST) track which typically runs at 40 mph as I recall.
High-speed slipping, on the other hand (which I think is far more of a design issue that has to be addressed) is something not requiring more than 'typical' perturbing effects on one or more drivers (and by extension on the resultant of driver pairs). The whole business of conjugation really concerns this more than any other effect on a high-powered duplex locomotive.
And just what is this expensive engineering experiment supposed to prove?? It's been over 70 years since a T1 turned a wheel in revenue service and the current iteration can't turn back time.
CSSHEGEWISCH And just what is this expensive engineering experiment supposed to prove?? It's been over 70 years since a T1 turned a wheel in revenue service and the current iteration can't turn back time.
http://rrpicturearchives.net/showPicture.aspx?id=5214216
Didn't 5547 perform better from a slipping standpoint when it was fitted with Walschaerts?
kgbw49Didn't 5547 perform better from a slipping standpoint when it was fitted with Walschaerts?
One of the principal reasons for high-speed slipping is the precision at high cyclic, the relatively large admission opening at high-speed running cutoff, and better breathing at exhaust of the Franklin System vs. what piston valves without compression control produce. The test results on the T1a show much the same loss of high-speed valve 'capacity' as in the initial K4 comparison that established type A as a priority for the new locomotives originally. (The contemporary argument, if we look through the files at the Hagley, was that on a railroad that didn't run actual trains much faster than 100mph, the piston-valve performance was perfectly adequate...)
Now the problem with an unconjugated duplex is that you only have four drivers putting down the 3200-odd ihp, so if one driver encounters a rapid partial unloading, like a patch of bad rail, a frog, or a low joint, the engine is more prone to slip if high pressure is applied to the piston (as it can be at very high speed, where the cutoff goes back to ~40% or better). With normal valves, there is insufficient mass flow to sustain the higher "speed" correlated to spinning, even though the load on the particular engine is reduced so 'less steam is needed to keep up rpm'. But the Franklin System has perfect events right up to where valve float starts to set in, and that is ridiculously high cyclic...
Low-speed slipping is affected by the same four-driver physics, but it is (in theory) much easier to arrest it, once you acknowledge it is a concern that can't be addressed with more sensible engine handling as built (spoiler alert if you are new to technical discussions of duplexes: it should have been more of a concern in design). It would have been worth it, since air throttles wound up being specified for the locomotive, to have designed headers around two separate front-end throttles, but the four Wagner throttles as on the low-pressure engine of the ACE 3000 would have done the job just as well for far less money using the differential gear already built on the Q2s. Keeping either the OC or RC valve drive.
People often talk about a locomotive not being used for its intended purpose. Probably the best known example of this is the C&O Allegheny. It was a speedster that was used in coal service. How about the T-1 was designed for a service that didn't exist. It was built to pull heavier passenger trains than were normal practice at speeds that most of the track couldn't sustain. It's "interesting" that other railroads with more knowledge of superpower steam (ATSF, NYC, etc) were perfectly happy with the Northern. I've said it before but matching a railroad that hadn't designed a locomotive in two generations with the stodgiest of the builders is just a recipe for disaster.
Actually, the T1 was better designed for its intended purpose than almost any of the contemporary high-speed express steam locomotives -- particularly on a PRR with many name trains too large for a single K4. The design criteria were 880 tons at a sustained 100mph max -- note that the T1 speedometers only read up to 100mph. This with less augment than any contemporary steam locomotive even remotely as capable... at initial design time. This was a bit like 'one and a half K4s' with only a nominal ~8mph higher speed -- but the T1 could do the job of a doubleheaded K4 at that 92mph all day long, on far less coal and water and, of course, half the crews...
Part of the 'overkill' was Baldwin and PRR making the engine configured for highest possible "speed" -- aside from the poppet valves, the absolute short stroke (as noted at Atlantic City, the main pin was as close to the axle bore as it could physically be, and the pin was then ground eccentric to further shorten the effective main-rod stroke -- this is much of the reason why the test locomotive stalled on C&O during their testing.
Note that the C1a also had the 26" stroke as designed (and NYC might have been able to make a little better use of it!) but development was just that little bit delayed...
Who cares about how much better it was than a K4. A K4 was at least two generations behind a T1 or Niagara. The PRR designed a one trick pony locomotive for heavy passenger trains right when there weren't that many anymore and the diesel was better.
My father use to relate anecdotes about the B&O and PRR racing each other with their same time departures from Washington Union Station. The B&O engines being used in the early 1920's would lose time after time to the PRR's K4 powered trains. However, once the B&O took delivery of their P7 (President Class) Pacifics in 1927 the advantage switched to the B&O who held sway until the PRR electrified the Washington-New York line; then the GG1 led trains walked away from the B&O's P7 powered trains.
Needless to say no T1's ever operated on the Washington-New York run.
Never too old to have a happy childhood!
BaltACDMy father use to relate anecdotes about the B&O and PRR racing each other with their same time departures from Washington Union Station. The B&O engines being used in the early 1920's would lose time after time to the PRR's K4 powered trains. However, once the B&O took delivery of their P7 (President Class) Pacifics in 1927 the advantage switched to the B&O who held sway until the PRR electrified the Washington-New York line; then the GG1 led trains walked away from the B&O's P7 powered trains.
Be fun to see what the performance of the James Emerson 4-4-4-4 might have been in this circumstance!
Or the B&O W-1 if it had been finished...
The smaller firebox on the George Emerson might have been a bit of a handicap.
Yes, comparatively small (at 80 square feet) but only 11 square feet smaller than a T1.
And this with the radiant uptake and circulation of a watertube firebox, and pressure of 350psi.
Interestingly: if you use a P-7 as a 'baseline', with 70' GA, scaling to 4 driver axles would give you only slightly more grate area than a T1 (93 and a fraction) without allowance for the better steam distribution and higher effective pressure in the duplex running gear...
Perhaps a better argument was the required shape restriction due to the rear cylinders and piping, not just the size restriction. It was amusing to see the lengths PRR went to on the rear-engine piping on the Q1, perhaps in perceived response to issues on B&O 5600...
One step at a time: https://youtu.be/lF9-TdDyJIA?si=TFfSes-8WiG2FEHF
Editor Emeritus, This Week at Amtrak
I think that both Amtrak, on the NEC, and California High Speed will be happy to hosdt the T-1 for demonstrationb of its high-speed capabilities.
An d I'd love to see a GG-1 restored as a rectifier dc-motored (original motors rewound) locomotive.
daveklepperI think that both Amtrak, on the NEC, and California High Speed will be happy to host the T-1 for demonstration of its high-speed capabilities.
To a lesser extent, that would apply to Amtrak in the most 'likely' place for high-speed operation (North Brunswick to Trenton approaches) BUT the great difficulty there would be insurance. Any "difficulty" might post a significant risk to traffic, or passenger safety, in that relatively-congested corridor, and little is gained by conducting high-speed runs at night (as Amtrak did with the Acela testing that nominally exceeded the official speed record held by the TurboTrain).
It would be delightful, of course, to have the locomotive run on a service similar to that to Warnambool in Australia (or Ross Rowland's excursions with 614 on ex-EL New Jersey Transit lines) but I think the risks and likely cost would be too high. Don't let that keep anyone from trying!
Of all the preserved steam capable of running at speeds over 85mph, 5550 would have by far the lowest issues with guiding and dynamic augment. Even with zero overbalance, the necessary lateral stiffness is lower than for 611, the next 'likeliest' contender for proper high-speed running balance.
Oh -- any remotored GG1 might as well be given full AC motors built to the connecting dimensions of the originals. These were carefully designed in the mid-Seventies (for one of the high speed GG1 proposals) and it would be child's play with modern CAD/CAM to design a comparable replacement using more modern or stock AC motors. Then a RPS hybrid arrangement workable with anything from 11kV to 50kV would be simple and straightforward to provide... which also solves the question of operating the locomotive when not 'under wire' and solves the 25Hz-60Hz issues more or less definitively.
Note that the annealing facility for the T1 frame would probably serve nicely to decrystallize a couple of GG1 underframes...
The NEC [Nothing Else Counts] and CAHSR are both ginormous money pits. Anything that would potentially cost more in maintenance of the ROW won't be justifiable even with positive press.
That said, I'm TOTALLY on board with baking a couple of GG-1 trucks.
Why can't we piggyback off the Japanese somewhere in the US as they pioneer MagLev as they are? So many dollars going into fanciful activities and concrete that'll be torn up in 20some years.
GrampWhy can't we piggyback off the Japanese somewhere in the US as they pioneer MagLev as they are? So many dollars going into fanciful activities and concrete that'll be torn up in 20some years.
With all due respect - it will take much longer than 20 year to put in place the concrete you expect to be removed in 20 years. You do what you know how to do with the resources that are available to you.
Maglev can be a speed demon, personally, there will need to be a lot of work to make it into a real TRANSPORATION SYSTEM, useable on a day in day out basis.
BaltACD Gramp Why can't we piggyback off the Japanese somewhere in the US as they pioneer MagLev as they are? So many dollars going into fanciful activities and concrete that'll be torn up in 20some years. With all due respect - it will take much longer than 20 year to put in place the concrete you expect to be removed in 20 years. You do what you know how to do with the resources that are available to you. Maglev can be a speed demon, personally, there will need to be a lot of work to make it into a real TRANSPORATION SYSTEM, useable on a day in day out basis.
Gramp Why can't we piggyback off the Japanese somewhere in the US as they pioneer MagLev as they are? So many dollars going into fanciful activities and concrete that'll be torn up in 20some years.
D.Carleton BaltACD Gramp Why can't we piggyback off the Japanese somewhere in the US as they pioneer MagLev as they are? So many dollars going into fanciful activities and concrete that'll be torn up in 20some years. With all due respect - it will take much longer than 20 year to put in place the concrete you expect to be removed in 20 years. You do what you know how to do with the resources that are available to you. Maglev can be a speed demon, personally, there will need to be a lot of work to make it into a real TRANSPORATION SYSTEM, useable on a day in day out basis. And you can't run a T-1 on a maglev track.
And you can't run a T-1 on a maglev track.
And I doubt the Class 1's will let the T-1 run on their rails if it ever gets built and operational.
Do they have the brainpower and finances to make a Maglev adapter for the T-1? Steam/Magnetic
BaltACD D.Carleton BaltACD Gramp Why can't we piggyback off the Japanese somewhere in the US as they pioneer MagLev as they are? So many dollars going into fanciful activities and concrete that'll be torn up in 20some years. With all due respect - it will take much longer than 20 year to put in place the concrete you expect to be removed in 20 years. You do what you know how to do with the resources that are available to you. Maglev can be a speed demon, personally, there will need to be a lot of work to make it into a real TRANSPORATION SYSTEM, useable on a day in day out basis. And you can't run a T-1 on a maglev track. And I doubt the Class 1's will let the T-1 run on their rails if it ever gets built and operational. Do they have the brainpower and finances to make a Maglev adapter for the T-1? Steam/Magnetic
The point is well-made. Realistically, the T1 clone won't have anywhere to run at the speeds and service for which it was designed. As far as PRR locomotives are concerned, an M1 would have been a better choice.
How about the Pueblo Test Track?
He means regular trips or excursions.
Keep in mind that even as built the design has the augment of a comparatively smaller locomotive, and if given zero overbalance would retain this up to any road speed insurance would permit. This was one of the intents of the duplex design.
It might also be remembered that the design was sized as a 'steam GG1' to operate in 80mph service, and its 'dash' capability (the "10% over service speed") as reflected on the speedometer was 100mph. Fits neatly into any operation with 79mph path limitation (as in NJT for the C&O 614 excursions) or current-of-traffic at 70mph.
daveklepperHow about the Pueblo Test Track?
For what purpose?
BaltACD daveklepper How about the Pueblo Test Track? For what purpose?
daveklepper How about the Pueblo Test Track?
Arrangements have already been confirmed to operate the locomotive on the Fast Loop at TTCI, and what needs to be incorporated in the locomotive design and construction to permit that. For those pathetic objectors who seem to think that FIA land-speed record requirements would have to apply to any putative result of that testing, remember that it is a loop. Energy storage as pressurized overcritical water in the boiler turned out to be a 'non-issue', although provision of suitable instrumented wheelsets is important.
It's probably important to repeat that merely "setting a railroad speed record" hasn't really been a major objective of the T1 Trust since the early days of the effort, and that most of the actual proof of ability for high-speed running will have been achieved via simulation and then testing on the roller rig long before anyone actually starts notching the thing up on a test track.
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