John Hankey presents a convincing argument against the myth of a Santa Fe 4-4-2 achieving 106 mph during the Walter Scott run. But there is an error in his description of the modest proportions of the engine. He says it has a “modest firebox area (190 square feet).”
Well, if he really means firebox volume, it would be cubic feet, not square feet. No big deal except you rarely see fireboxes described by their volume in cubic feet. More commonly we refer to grate area in square feet. If he really meant grate area, then the number 190 is wildly inaccurate. The largest ever grate was applied to the NP Z-5 Yellowstone - 182 square feet. Typical of 4-4-2s of the day, the Pennsy E3sd sported a 55.5 square foot grate and the E6s was slightly smaller at 54.75 square feet. Grate area determines the size of the coal bed and much of the airflow to the fire, so it is critical to engine performance.
So I hope Mr. Hankey or an editor will see this post and clarify what he meant to say. This is not to question or criticize his argument. He is certainly correct.
As I understand it: thermodynamics; the usual rules of physics for conservation of energy; the usual rules of mechanics for power used <= and balancing the power produced for a constant speed at a certain level of train resistance; and most critically, the huge increment in power needed to suddenly accelerate that train from the lower speed in the immediately preceding mile to the 106 MPH rate in the measured mile - where did that power come from all of a sudden ? Kind of like me jogging at my usual torpid pace, then all of a sudden going at a 4-minute mile pace, then back to the slower slog. Plus, comparing this loco and run to other similar locos and runs - it doesn’t ‘jibe’.
Finally, my point is that if this run were credible and repeatable, everyone else would have changed the proportions of their locomotives to match ASAP so as to also reap the same benefit - imitation being flattery, and all that - but that didn’t happen.
I guess I will have to read the article, and also read up on that speed run. I think Trains covered that event in some long ago back issue. But I must say that I am skeptical of Hankey’s conclusion, as I understand your explanation of it. But setting that aside, I do not understand what reason there is to doubt a speed claim of 106 mph from a 4-4-2 locomotive and train of that era. I could understand the doubt if there were some type of timekeeping or mileage error that could be shown.
But specifically relating to your explanation of Hankey’s conclusion, why would there need to be a sudden acceleration to get up to speed within a limited distance before entering the measured mile? Do we even know that that was the case? I would assume that if one were to clock a top possible speed in a measured mile, one would make sure the train was
I just received my Trains today and may not get to read it until Monday or Tuesday. However, as to other railroads as well as the Sante Fe adapting locomotives to the same: simply the engine and railroad were specially prepared to allow for the fastest passage of the train. Quality coal and water, the most skilled engineers of the divisions, spiked switches, well cleared meets and overtakes, etc., all things that are too expensive and time consuming to do under ordinary operating circumstances.
Hankey was referring to the direct heating surface (firebox and later combustion chamber) of the locomotive, not the grate area. 4-4-2’s of the era would have had something in the range of 190 Sf of direct heating surface. This is where most of the heat transfer takes place. The tubes and flues constitute the indirect heating surface where additional heat from combustion gasses is transferred to the water in the boiler…
Speed timings for this run would have been ‘timed’ by Operators reporting OS times for the train past their station. Those times are reported in Hour and Minute…NO Seconds are reported.
Can’t speak to the road where the timing occurred, however, I suspect all railroads at the time had procedures in place for all ‘Standard Clocks’ to be synchronized on a daily basis. On my carrier this synchronization procedure was transmitted on the Dispatcher’s Wire at Noon, daily. This leads to the question, were all clocks actually keeping ‘the same’ time. Was the operator reporting the time reporting 55-59 seconds as the actual minute or the next minute. We can time things to the nano nano second accuracy today - we could not then.
One minute (plus or minus) on a OS reporting can have a big difference on the calculated speeds between two points.
“From the little hamlet of Cameron to the still smaller one of Surrey is 2.8 miles. “She” made in one minute and thirty-five seconds at a rate of 106 miles an hour.”
From that description, they must have had the ability to count seconds.
Again I’ve not red this article yet…but from past articles and understandings everybody was holding stop watches: trainmen, trainmasters, superindentants, on lookers, gawkers, operators, agents, the bulls, and, if he weren’t otherwise occupied by companions and consumptions, Scotty himself. And I bet the PR people took the best times off each watch at each inch! That’s what Scotty was paying for and that’s what the public gobbled up.
I’ve got a lot of respect for John Hankey, he’s gone places and done things I would have loved to do and done them well. That being said, maybe he just had to write an article about SOMETHING and debunking Death Valley Scotty’s run was as good a subject as any. Or maybe he just felt like stirring up some “stuff”, if you know what I mean. Love ya John, keep up the good work!
In a letter in Rwy Age for 25 April 1936, M. D. Franey said an LS&MS 4-6-2 had run the 7.53 miles from Amherst to Vermilion OH in three minutes. No one can show a timekeeping error, and probably no one can show a mileage error. So, no reason to doubt it?
That may be, but it is a readily understandable way to make my point that actual physical results can be calculated mathematically, only to turn out differently than predicted because the calculation was in error, or more commonly, did not take into account the full range of variables that applied.
But, as I said before, if Mr. Hankey calculated that 106.1 mph was not possible, he surely must have found what speed was possible in that same calculation. And I cannot believe that he would not state that for the record in the Trains article. However, until I see the article, I can only assume he does state the maximum possible speed in the article.
The word, debunk is a strong, utterly confident word. It does not mean that you merely question or take issue with something.
Not meaning to debunk your math, but, with all due respect, I have a sneaking suspicion that your calculation is off by 5.4 mph. Perhaps Mr. Hankey made a similar error.
By the way, which locomotive are we talking about for the claim of 106.1 m
I’ve just reread Mr Hankey’s sidebar. He doubts both the accuracy of
the timing and also the ability of the locomotive.
No one knows who did the time measurement (1m 35s over 2.8 mi), but
perhaps someone among the party used his own watch? If the time were
1m 40sec instead of 5 seconds shorter, the speed would have been 100.8
mph - still plenty fast, it seems to me.
For the part of his claim based on the locomotive, the author invoked
a conversation with Mr. Bill Withuhn, who studied speed claims for
steam locomotives from 1893 and 1905.
Hankey writes “In his (BW’s) opinion, neither locomotive - and
certainly not Santa Fe No. 510 - could have generated the boiler
output or cylinder horsepower needed to accelerate their trains past
80 or 90 mph under ideal conditions. Furthermore it is hard to
imagine that a fireman could shovel enough coal …” “The boiler
couldn’t have made steam quickly enough,…”