Saint Class 135 ish mph

Bear in mind a saturated steam boiler will produce more lbs/hour than the same boiler when superheated. (it has more evaporative surface) Of course each lb of steam contains less energy and occupies less space then from a superheated boiler. I would imagine a saturated steam saint could produce circa 1100 ihp continuously (say 24,000 lbs/hour) and 1400-1500 ihp if really pushed (say 32,000 lbs/hr)

as to the power required - this is my estimate - feel free to check and critique

 

1 - some people doubted that anyone would run a light engine at high speed - so another example to show it was "normal" practice
2 - someone asked if anyone else apart from GWR did high speed light engine tests - so yes, various railways did (see Bridge Stress Committee report)
3 - I thought you would appreciate a Darlington loco entering the debate

 

I had to dig for my copy of "Saints and Sinners". On page 101 it shows the reversing lever quadrant. Its lowest setting is 22%. Perform says that steam
consumption is around 42KLbs, double the standard amount.
Kind regards
Jos Koopmans

 

Jos - You need to close the regulator a bit. Suggest lower the steam chest pressure until you get about 1000-1200 ihp (as that is the approx power required), and then see if the steam consumption is reasonable. Also note if you set a given cut-off for the front half, the back half of the cylinder has a higher cut-off, as the program doesn't compensate the valve events to give approx same cut-off in both ends as a real valve train would do (ie countering effect of con rod angularity). So the average cut-off is higher than the figure you enter.

------------------------------------
Adrian Vaughan kindly provided the following comments on high speed light engine trials and signalling thereof on the GWR elist group...

I had a good friend, Ernie Nutty who was a Swindon Works apprentice 1920-27 and then to the Drawing Office was aqn 'outside Inspector, a rider of footplates to assess complaints from drivers and design remedies, who re-draughted the 'Manors' so that they steamed properly and ended up as Chief Assistant to S.O.Ell in 1948.

Ernie told me that as an apprentice he rode a 'Saint' on trial straight from the works, 'Light' gently to Stoke Gifford and if all was well to run home to Swindon up the bank to Badminton and then 'hell for leather' to Brinkworth. That is where these extreme speeds were reached. Ernie said he'd timed 120 mph running 'light' - BUT, he cautioned me - at any sort of high speed like that you couldn't say you stopped the watch at precisely the right moment because the footplate was shaking and the mile post was gone by in a micro second. All you could say is that you were gong well over 100 mph. He was involved with 6015 when they'd fitted it with the double blast pipe and chimney. He said him and Insp. Billy Andress rode on it on a Padd- Plymouth public, scheduled, express and they'd timed 108 before Heywood Road Jc - that's all gently downhill. They'd gone back to Swindon and told S.O Ell and he'd gone out and timed 115! Both figures in Ernie's opinion to be taken with a pinch of salt because the times were taken with a hand held stop watch from the footplate. That was the opinion of a first class locomotive engineer.

I am sure that the signalmen would be aware that the light engine, all gleaming and clearly a 'Trials' engine would need a clear road for the return journey. 'Trials' engines were a daily feature of the line between Stoke Gifford and Wootton Basset. They'd turn on the Filton triangle and be signalled away from Stoke Gifford when they had a clear path. The railway them days and even in my early years, was run by the men. The signalmen knew what to do. They were interested.

I twice got a clear road for a train out of the Down Relief Line from Challow. One of those trains was hauled by a DIESEL(!) called Falcon. The driver, Reggie Pratt, a great friend who I'd ridden with on steam engines, wanted to show me what this diesel could do with 450 tons of 8-wh. parcels vans. I go the road cleared and boards off over both Knighton and Ashbury Crossings and Shrivenham pulled off too because that was a very short section Ashbury to Shrivenham. We were in charge of the railway and, choosing our moment we could do what we liked. Reggie wound up the 'Falcon" - once the long train had got clear out of the Down Relief onto the Down Main - and it went like a rocket!

Best wishes,

Adrian Vaughan

 

Also from Adrian Vaughan...




On 16 May 1928, No.6004 King George 111 built July 1927 was run 'light' from Swindon to Didcot - turned on the Didcot triangle and returned. This was done twice that day, the maximum speed was 102 mph on the DOWN journey, 2nd run.
Driver 'Clem' Crook and Fireman Humphries. Swindon men.

The purpose of this was to see how hot the leading axle boxes of the bogie became under extreme speed. I will put my evidence on this site. This takes the form of a postcard photo given to me by Driver Crook's family showing the front of the engine upon whose buffer beam two Swindon drawing office men sat at 102 mph taking readings from a thermometer. Each man sat on a wooden box with a padded sack on top. Only one man is shown in the photo but there are two boxes. The postcard image was not properly washed free of chemical after 'fixing' and after 80+ years had become very bleached. On the writing side of the postcard are the details of the run.

The family of the driver wanted this epic to be widely known. It took place on a Wednesday. There must have been Special Instructions for the signalling of it because of the extreme speed with relatively little brake power. You'd expect to do it on a Sunday but they chose a Wednesday! The other thing is, of course, the fact that two men sat on the buffer beam watching the thermometers. I asked Alan Peck, Works Apprentice. lifetime employee at Swindon Works and finally Engineer in charge of the maintenance of the buildings, if he recognised the man in the photo. He said he did. A Drawing Office man, and quite capable of volunteering for such a crazy job. There must have been two men - there are two stools and I cannot believe that one man walked across the buffer beam to watch both thermometers! I hardly dare believe the evidence of the photo!

As a post script. Driver Crook was misled by his fireman into passing a signal at 'Danger' at Challow near the end of his career and was taken off driving except within the confines of the Swindon shed. He became a 'Shed Turner'.

 

I would suggest that the advice of the late Mr. Nutty, whom I was acquainted with very slightly indeed and was no "blind Swindonite", on the need to take these things with a pinch of salt, was sbsolutely so.

PH

 

I am not that much interested in the details. The steam chest pressure can be adapted in the Perform data and as long as the Tractive Effort is larger than the
locomotive's resistance it will accelerate. Anyone capable of some Excel calculations could reproduce the the 1906 travel:
a) determine the locomotive resistance say from 70 mph to 140 mph
b) use Perform to determine a useful TE at these velocities by adapting steamchest pressure
c) determine the difference, I suggest to produce a regression formula
d) determine the acceleration for say 20 second intervals using Newtons F=ma
e) speed increase is acceleration times 20 seconds, path length = (V +dV)*20
f) redo with newly calculated velocity for the next 20 seconds.
And so on until there is insufficient Tractive Effort.
It is quite fun to do, I'll abstain having done that sufficiently in the past!
Kind regards
Jos Koopmans

 

Don't waste your time Jos. The GWR fanboys are totally enamored with the thought of the GWR designers charging up and down the main line like a bunch of late Victorian cafe racers. It'll take more than science to dissuade them.

 

If it was true, I'm sure I'd find a contemporary newspaper report of two bodies by the side of the line, which would be the inevitable result of riding on the front of a steam loco at anything like this speed. My immediate conclusion is that it belongs among those fishermen's tales we hear from time to time, along with all the other claims in this thread.
Must admit that I've not looked for any such newspaper reports, though.......

 

[FX Sigh]. They would presumably have been inside an indicator shelter. You do know what that is do you?

I don't know what it is about this thread, but I really don't understand why anyone still has any doubt that the GWR did run light engine at high speed for testing purposes.

I suppose I do, reluctantly, understand why people are having trouble understanding that the statement "we measured 120mph with very little precision" is utterly different to the statement "we were running at exactly 120mph".

 

I can't imagine they held onto the lamp brackets for dear life at 90MPH somehow

 

If they measured a speed with "very little precision," why mention the speed at all? I can imagine the derision if the LNER had not used the dynamometer car with 4468 but relied instead on HNG's large chronometer whilst he was riding the footplate and making a similar statement regarding 3.7.1938.

 

This is the nub of the matter. No official record was (or is) being claimed. Far from being an issue of 'Swindonite' bias, it's one of "was it technically plausible?"

Leaving aside, for a moment, issues of operating a stopwatch accurately on a "lively" footplate, I'll return to the subject of fuel. Courier (post #180) referred to the properties of decent sized lumps of coal. It seems reasonable to assume that as much care was taken selecting the best quality (decent sized lumps) of coal available for such planned high performance jaunts as would be necessary for all other variables (clear road, known track conditions, civil engineer away on holiday etc.), the more so if a senior member of the CMEs team was going to be on board.

T'would seem from musings tekkie that the Swindon No1 boiler probably was indeed able to produce steam in the quantaties required to comfortably exceed the ton.

Quite how good the steam circuit on the 29s was isn't yet clear, at least, not to me! A few earlier posts allude to distribution in 2cyl GWR locos presenting less problems than for 4cyls.... seems reasonable enough when computing power was limited to slide rules & abacuses (or abaci if you prefer - both pluralisations are perfectly cromulent!). Anyhoo, the 'two missing cylinders' would seem to weigh towards more, rather than less likely.

For my part, I've seen nowt yet that totally rules out something rather special having happened 111 years ago, but equally see no way any definite top speed could accurately be determined from those measurements made under conditions described. It seems odd that no-one mentioned the sound of the loco over rail joints. Wasn't that an indicator of speed to experienced drivers?

 

Different people have different interpretations of "high speed" figures, even if inaccurate, give perspective.

 

Did GWR have a dynamometer car at the time? If they were interested in what the locos could do at the extreme end of their performance, it would make sense to measure it.

 

Because no one's trying to claim a record here. Merely that a Saint went bloody fast!

Sent from my Moto G (4) using Tapatalk

 

Correct!

 

Sorry Alex but it is not at issue that the locomotive went very fast. It is the attempts to "big it up" which turn the whole thing into the realms of "pub talk" in much the same way as similar clams in the U.S.A. do. Again see Mr, Nutty's observations about a pinch of salt being required. He was as "copper capped" as anybody but had a sense of proportion.

Paul H

 

I'd say quite the opposite in fact. From my reading of the thead, I'd say those who think there is some truth to the story (now stories) have taken quite a proportioned approach. A good deal of this thread has been devoted to the discusion of is such a thing actually possible and what are the limiting factors.

I think you wasted too many words in this thread Paul....."Bah humbug" would have done the job just just as well.

 

I'm surprised you haven't called for Paul to be charged with heresy.