611 going 100 MPH is anecdotal, as I've talked with several key people on the NS steam program and not one has ever confirmed the rumor.
Mallard only did the one record run downhill and that was that.
It's part of the PreWar German argument that the Mallard run wasn't kosher.

I believe the claim of 611 going 100mph was during a 1959 excursion put on by the N&W at the end of the steam era, which makes it completely believable. I don't believe 611 was run that fast in the "excursion era." I do believe before the 1986 Dismal Swamp accident it was common place to run track speed, including 75+ on the NKP East of Fort Wayne.

Another argument thrown around against Mallard's record is that it apparently overheated it's bearings to the point of needing a tow to be repaired afterwards.

In its excursion era operations, never as far as I knew. But 79 mph was attained numerous times when I was up front. Our biggest hope to run was on the joint Santa Fe track going to Kansas City where the speed limit was, if I recall correctly, over 90 or 95, but the Santa Fe trainmaster climbed up in the cab with a stack of speed restrictions...

However, in real life, the Class Js routinely ran at 100 mph on the racetrack between Norfolk and Petersburg, and in places in southern Ohio, that from interviews with multiple engineers over the years, and in fact, depicted in the N&W Company film: The Modern Coal Burning Steam Locomotive (1944), depicting the speedometer hovering just at and above 100 mph.

Best
Ken Miller

OK, what if we all only had 9 fingers (like I do) would we be so interested in a 81 MPH speed record? Why obsess on 100?

The issue of sustainability has also been raised. I'd argue that boiler explosions resulted in a higher speed of movement (but for a shorter duration) if sustainability is not included, but who wants to compare those?

The practical limit on high speed rail transit is roadbed, not variety of power. Electric has traditional steam beat to far higher than 100 MPH in regular sustainable service in more civilized parts of the world that believe in investment in high speed rail.

Maybe our mental energies could be more practically applied to making a sustainable version of traditional style steam with technological improvements to provide both the nostalgic and broader economic benefit at more realistic speeds for real world conditions.

Wrong-ish, and wrong.

Look, any partisan can find something to nitpick in a competing record. The German 125-mph record claimed before Mallard was a short train on level track; Mallard was a full train. The "downhill" aspect is not like, say, running down a helper district. The grade is slight; I can't even find a listing for the actual rise but I believe it's only about 0.6%--but thirteen miles long. To this day it remains a favourite spot for loco performance timing, either uphill or down.

Here's Wikipedia's account of the "severe damage" to Mallard:


This is indeed a failure preventing its continued operation on a train, but it did not "need a tow." It simply limped back to Doncaster.

The Gresley conjugated three-cylinder valve gear design was a complicated beast designed to extract maximum speed and power out of a small package, much like sports car engine and transmission developments. The big-end problems are part of why it did not take off in popularity with other three-cylinder loco builders.

Good point. My mother grew up in a well to do family in western Illinois in the 30's. She reminisced to me about family trips, taking the CB&Q into Chicago for shopping day trips, riding in the observation car. She said that the parlor end of the car would have a large speedometer arranged horizontally in the center of the area like a bird bath for everyone to see. Often, that speedometer registered over 100 on the way to the city. I would assume that these trains would have been pulled by CB&Q's Hudsons.

My point is that prior to the ICC mandated speed limits being implemented (circa 1949?), it was pretty common for class I RR's to operate at 100 plus where the track allowed.

When the Reichsbahn did the speed record on may 11th, 1936, it was part of a series of promotional trains to persuade the government officials to invest into a high-speed train system which was to be powered by diesel railcars as well as steam locomotives.

05 002 which did the well documented speed record was only one of two engines of that class, theoretically well capable of going even faster (no expert comparing the technical data to the Mallard class will deny this), but as there have been some high brass officials in the train, it was the goal just to break the magic 200 kph mark, which it did that day. No reason to have her going faster or to risk a failure.

Mallard, however, was smaller and weaker but being part of a series of 35 locomotives they considered it worthy to take a small risk to get the world record to Great Britain. That record is undisputed as well as the fact the line was slightly downhill and the locomotive was at her mechanical limit.




As to your "short train" vs. "full train", this was 197 tons vs. 240 tons. British coaches were significantly lighter than German coaches.


Citation:

"The gradient profile and speeds are by reference to C J Allen's "Locomotive Practice and Performance in the 20th Century", and other sources. Mallard had a long and at times, steep, downhill route. Three miles at 1/178, just over a mile and a half at Level or down at 1/330, then more than four and a half miles straight off at 1/200 gave an excellent platform for the high speed attempt. Despite Mallard's slightly heavier train weight these grades still provided an enormous advantage over 05 002. "

There is no evidence whatsoever that "the Germans" did try to get back the world record after the Mallard record run!

Instead, after 05 002's success, the Reichsbahn had ordered a big fleet of hundreds of streamlined pacifics, smaller than the 05 but bigger than the british A4 class. But when the first of these locomotives was delivered, it was only three days until WWII began and the main bulk of all these machines was cancelled in favour of thousands of Kriegsloks.

Mike

Kelly -

There was that sign on the Milwaukee Road between Chicago and Milwaukee that said "SLOW TO 90".


Les

There is a well reported story of a T1 that got the fireman and engineer in trouble on a mail train in the transition era. They got caught doing well over 110+ by a trainmaster and when they got into Fort Wayne were asked which one had the pilot's license. It was reported they made the run from the Ohio state line to Fort Wayne a distance of 18 miles in less than 10 minutes time including stopping in Fort Wayne. The T1 will easily break that speed record and should top 130 to 140 easy. The HP is there and if they get the drivers in balance they may break 150

Keep in mind, kiddees, that there is as much kinetic energy involved in going from 6omph to 80mph as there is to accelerate from zero up to 60. (The 80mph criterion in the Esch Act specifically involved this, btw.)

The same proportions apply to other speeds, while the air resistance starts going up as the cube of the speed... we might remember that in 1938, the C&NW E-4b tested by the AAR, very similar to the vaunted Milwaukee F7 class with 84" drivers, couldn't even make 100mph with the test consist. The equally reputed ATSF 3460 class could easily run 100mph, were severely valve-limited at 105, and probably couldn't reach 110 unless falling straight down, despite Baldwin claiming they were "120mph locomotives". I had hoped to see Project 130 prove or disprove this, but apparently not.

I have on reasonable authority that 614 can reach very near 100mph; if rebalanced, I would have little doubt. Strictly for the record.

One of the arguments in the timeless topic of the DR class 05 is that the testing was looking not at the 'magic ton' but as the magic metric 'double ton -- 200km/h (for a locomotive rated to 174km/h) They got just a tad over that, and then slowed down...
Part of the fibbing claim that Mallard reached 126.1 is that it is just comfortably above what was reported for the German engine...

Something that might be mentioned in context, though, is that Gottwaldt, who wrote a number of books about the DR streamlined power, reported that at highest speed the locomotive made a terrifying kind of howl, not a sustained reciprocating-steam sort of noise. To me this might suggest that the draft was at the point of 'stalling' the flow of combustion gas being entrained by the front-end arrangement -- when that action abruptly falls to lower effectiveness, the steam-generation ability will rapidly decrease, and as mass flow is probably high (I don't remember the exact cutoff percentage for the 05, but it was probably in line with the 40 to 43% observed across a fairly good range of engines balanced to that speed that are actually pulling a train, I'd guess it might be relatively quick...

The issue with T1 high speed, aside from induced high-speed slipping and recovery, is the likely presence of critical speeds in the machinery. At speeds above 120mph, you don't 'ride through' a harmonic resonance in the running gear to 'get to the other side'. Proper multiphysics ought to at least indicate where the critical speeds might be, and how quickly onset might be expected. The problem is that some of the forces might present quickly enough that feedback from the wheel instrumentation can't be 'acted on' in the number of driver revolutions producing dangerous resonant amplification.

I still think the next "high speed" project ought to be a Milwaukee A class, which the president of their builder said would easily go 128mph or better. Now that we know about proper strategies of overbalance... hmmmm.

Assuming you mean the PRR T1 "replica" (not getting into the "new build" hype) being constructed:

Where?
On what railroad?



I have read several engineering analyses over the decades that have suggested, repeatedly, that because of a variety of such factors involving the physics, thermodynamics, etc. involved, insofar as building a steam locomotive to standard gauge under what is considered normal and practical usage--in other words, not creating a special 550-psi boiler, not using exotic metallurgy, being able to actually fit the loading gauge, using typical track in top condition, etc.--200 kmph/125 mph should be considered the upper limits of what is achievable with steam traction. These analyses, of course, didn't examine the prospects of broad gauge such as Russian or Spanish tracks, or for that matter Hitler's proposed three-meter-gauge network.

In all honesty, the only way to prove this wrong with a "new" T1 build would be to export it to some trackage built to handle such high speeds such as the French TGV or Japan's Shinkansen--or wait until enough of California's HSR line is built. And then get permission to try a test run, provided it can clear the foreign loading gauge.

Frankly, I would be deeply disappointed if the Test Track near Pueblo Colorado could not handle the speed record attempts.

Did not the same facilities handle the Acela version one and two higher speed testing that aimed for a couple dozen more MPH?

https://railroads.dot.gov/program-areas ... -equipment

As for the other opinion, please explain why the technicians from Franklin Valve company clocked anecdotal evidence that your opinion is too conservative. It's not like those technicians would be foaming at the mouth in the defense of their employer. Their feedback helped lead to changes in design that reduced the poppet valve failures.

Frankly it would be neat to see the 5550 thundering through the speedway between New Brunswick and Trenton. That said, I think it is too tall to be even towed through Penn Station New York. How about leaving from Hoboken Terminal?

I suppose it would be more realistic (I know - not at all realistic) to do the Pennsylvanian from 30th Street Station to Pittsburgh leg - just like the diesels do now. IIRC there are some places between Paoili and Harrisburg PA that have maximum operating speeds over one hundred MPH.

Just a reminder that a couple bottles of cheap booze worth of my entertainment budget is a monthly donation to the T1 Trust.

Brian

1) The test track in question is owned and operated by the Federal Railroad Administration, and administered by the Association of American Railroads. How will they be convinced to allow such a test run, and to what ends and what fees to be assessed?
2) The high-speed test track at Pueblo has catenary, and is 13.5 miles long. Will the T1 run without fouling the catenary?
3) How does one get the loco to Pueblo (heluva flatcar....), and who pays for the trip from and to wherever it will be based?

Is this beginning to sound like a whole new GoFundMe fundraiser?



Key word: "anecdotal."

Sometimes I get the impression that a person has not even read the previous posts in the same thread they are commenting on before they open up with both revolvers blazing away.

Brian