so, who's faster then

[sir douglas]

The pennsylvania S1 reputedly went over 130mph and another apparently did over 140mph and werent even trying to set any records, they were just doing their job and happened to do it in the process but no dyno car and no official record while Mallard had to go downhill while falling apart to set the record, the yanks werent bothered with the official speed records at the time but now a group is building a Pennsy T1 which is similar to the S1 but a bit smaller, The T1 theoretically could beat Mallard's record and to prove that it can de done

 

[nightstar.train]

I've heard people say this, but I think it's a load of tosh. It was the 1930s. Speed was everything. Liners competed on the transatlantic crossing to be the fastest, trains all over Europe were competing for the speed record. If the American railroads could truly do better than Mallard they'd have found some way to prove it. 

[RichardT]

I think that “reputedly” and “apparently” are doing a lot of heavy lifting in the OP…

 

Richard

[adb968008]

Having seen and ridden the state of American track, i’m having none of it.

[The Johnster]

The Pennsy claims, 1940s not 30s for the T1 btw, were based on speedometer readings, and particularly suspect in view of the Duplex's tendency to slip, even at high speeds.  This is because when you have two sets of separately coupled wheels driven by two sets of separate cylinders in the same frame bed, if one set loses contact with the rails for even a nanosecond, the other set has the entire load of the train instantly dumped on it, and begins to slip.  The original set, when it picks up again, is trying to also handle the load of the entire train and starts to slip as well, and it is sometimes some time before things are back in order with all the driving wheels gripping the railhead and hauling the train.  The speedo in the cab is of course cable driven from a driving wheel, and will record the wheel's rotational speed expressed on the dial as the linear speed of the wheel gripping the railhead, not the speed of the actual loco if the driving wheels are slipping.

 

This is not to say that those speeds were not possible with those locomotives; they undoubtedly were in theory, but it is highly doubtful that they were ever actually achieved.  The shrouding of the engines was a matter of stylistics, not proper streamlining, and they were not especially 'slippery' through the air.  The T1's driving wheels would not give any edge over an A4 (6'10", 80" for both engines) in giving a higher speed at the railhead for a given rate of piston strokes, though the S1's drivers were 4" larger, but against that larger diameter wheels mean that the loco is 'higher geared', so wind resistance and other factors that impinge on the power output will have a greater effect.  Actually moving at those sorts of speeds may be possible, but requires wholly favourable conditions most of which are not under the driver's control!

 

Excessive speed in normal service (and TTBOMK these were the conditions under which the claimed speeds were achieved) is not a good way to run a train.  It is wasteful of fuel, demands more maintenance of the loco, is not kind to the track, and even if it is done safely and within speed and braking limits, on a busy main line the train will inevitably catch up with the preceeding service and have to slow down in response to caution signals.  It is also dangerous for those working on or around the track as well, as they will not be expecting the train to be upon them is a shorter time than normal for that route; this is what happened on City of Truro's 100+mph run down Wellington Bank in 1904.  Workers on the track were tardy in clearing off it and Driver Clemens had to put the brake in.

 

Of course, a Pennsy driver saying that he had the speedo up to 140mph is not necessarily lying, even if the train was only doing 90, because of the false reading of the speedo with the slipping wheels.

[roythebus1]

I've drivn 508s that went from 0-60 in 2 seconds, and back to 0 in 5 seconds as the WSP cuts in. An 87 from 15 to 110 in Watford tunnel with 1200 tons of freightliner on a very damp day.

[jonhall]

there is a quite good argument put forward in favour of the Germans http://www.germansteam.co.uk/FastestLoco/fastestloco.html

[jjb1970]

It's always an interesting argument but to claim bragging rights performance has to be verified, not anecdotal. The big PRR duplex kettles were magnificent machines and in that era US passenger trains could and did operate at high speed but whether or not they beat Mallard is conjecture. Possible,  I don't discount it, but once you open the box of what might have happened then anything is possible. 

 

If people were that bothered then it'd be easy enough to just design and build a record breaker. I would rather see a group do that than the practice of building replicas. That said it'd be a bit empty, like the craze a few years ago to take the Atlantic blue riband using specially built small high speed craft to beat liners built 50+ years earlier which did it carrying thousands of people.  OK, you took the record but does it really impress anyone or mean much?

[Steamport Southport]

3 hours ago, jjb1970 said:

It's always an interesting argument but to claim bragging rights performance has to be verified, not anecdotal. The big PRR duplex kettles were magnificent machines and in that era US passenger trains could and did operate at high speed but whether or not they beat Mallard is conjecture. Possible,  I don't discount it, but once you open the box of what might have happened then anything is possible. 

 

If people were that bothered then it'd be easy enough to just design and build a record breaker. I would rather see a group do that than the practice of building replicas. That said it'd be a bit empty, like the craze a few years ago to take the Atlantic blue riband using specially built small high speed craft to beat liners built 50+ years earlier which did it carrying thousands of people.  OK, you took the record but does it really impress anyone or mean much?

 

Very few people are building replicas though. Apart from the "early" locomotives such as Rocket and Locomotion all the others are new builds or using parts which are readily available such as in the Saint.

 

Which makes sense when you look at how much it would cost to overhaul 60009 compared to building the P2. A 100 year old locomotive is just that. It's 100 year old metal. A new one will last for the next 100 years. That's why people are building new ones, not because they are just looking at the past. If someone would cough up the millions needed to overhaul 60009 then I would expect them to be open to the suggestion.

 

Are people going to pay to travel behind the 5AT or Tornado? I'm afraid the A1 has it. In fact they only went for the 5AT concept as they thought they could get a cheap 5MT from Barry Scrapyard and they've all steamed now.

 

 

Jason

[jjb1970]

I really can't get enthusiastic about these new builds. A new kettle designed to push the concept to a limit achievable with state of the art design, manufacturing and materials would still just confirm it's an obsolete technology woefully inefficient and outclassed by alternatives such as electric traction but at least it'd be interesting. 

[APOLLO]

I have read the PRR Duplexes were very slip prone so I doubt that claim.

 

The New York Central perhaps had a contender, The mighty Niagara, sadly all were scrapped. We will never know.

 

 

Mallard it is, her run was authenticated with a dynamometer car.

 

Brit15

 

 

 

 

[The Johnster]

I regard everyday service performance as far more meaningful than one-off speed record attempt, and becuase of that am much more impressed by the NYC Niagaras, 1,000tons at 100mph in daily service, to my view the ultimate express passenger steam locomotive of all time.  The Pennsy seems to have sacrifiied reliable daily performance on a hillier route for impressive-looking and highly stylised duplexes which were more suited to the more level NYC, who were doing very well indeed with the same number of wheels in a non-duplex arrangement. 

 

You'll gather from this that I'm not a fan of Duplexes.  I don't see the point, and they are bound to be prone to slipping for the reason I have pointed out on anything but a perfectly level road.  If you thought starting heavy trains was difficult with pacifics, these would have been a terrible shock to you...

 

That said, I can only hope that the T1 rebuild is succcessful; perhaps modern anti-slip technology can reform the design, and would, honestly, like to see the engine achieve the genuine and properly verified 140mph it's builders want from it.  But unless they've sorted the slipping problem, they've got no chance!

[hexagon789]

1 hour ago, The Johnster said:

NYC Niagaras, 1,000tons at 100mph in daily service, to my view the ultimate express passenger steam locomotive of all time.  The Pennsy seems to have sacrifiied reliable daily performance on a hillier route for impressive-looking and highly stylised duplexes which were more suited to the more level NYC, who were doing very well indeed with the same number of wheels in a non-duplex arrangement. 

The NYC MAS was 85mph, and they were quite strict about compliance, perhaps the strictest railroad, others were very more concerned aboit image and timekeeping. Nevertherless, 6mph in excess of linespeed was an automatic 3 demerit points on an engineer's record - reach 12 and there were official sanctions.

 

Now I know the Niagras were capable of higher speeds, though 95mph is the official maximum recorded, but I'm suspicious of 100mph in daily service given the NYC 85mph ceiling (most mainline routes were only 80) and strict compliance measures.

 

The Pennsy had an 80mph ceiling.

 

Indeed, only two 'roads' officially permitted 100mph in the steam era - the Milwaukee and the Santa Fe. The IC only upgraded to 100mph in the diesel era and never permitted steam locos to officially run at such speeds.

 

Official Employee Timetables, many available freely online document, the permissible speeds for reference.

[009 micro modeller]

11 hours ago, jjb1970 said:

If people were that bothered then it'd be easy enough to just design and build a record breaker. I would rather see a group do that than the practice of building replicas. That said it'd be a bit empty, like the craze a few years ago to take the Atlantic blue riband using specially built small high speed craft to beat liners built 50+ years earlier which did it carrying thousands of people.  OK, you took the record but does it really impress anyone or mean much?

 

7 hours ago, jjb1970 said:

I really can't get enthusiastic about these new builds. A new kettle designed to push the concept to a limit achievable with state of the art design, manufacturing and materials would still just confirm it's an obsolete technology woefully inefficient and outclassed by alternatives such as electric traction but at least it'd be interesting. 

It’s an interesting one - I think one of the loco groups (it might even have been the A1SLT although I don’t know if Tornado would even be suitable - not streamlined for instance) who run on the main line were asked a few years ago whether they would consider trying to beat Mallard’s record if they had the opportunity, and the consensus seemed to be that even if it was practically and technically possible it would be better to leave it in the past and not detract from the historical event of the original record-breaking run.

 

Regarding replicas, I can see the point with something like Rocket or the Steam Elephant - they’re very early locos, and there is actually a genuine heritage/educational point to having them around and being able to experience them actually operating, where the original either no longer exists or is too fragile or historically important to restore to working order. In many ways this argument extends to the NG new-build/replicas (L&B etc.) and some of the ‘more modern’ standard gauge ones. Then there are new locos built to new or existing designs (mostly NG/miniature admittedly - see Kirklees or Bure Valley) because their owners want to run steam and need a suitable design, which seems sensible enough. I can’t really see the point though in a new loco, to an entirely/mostly new design, designed solely to set a new world speed record for steam locos (which Mallard and its contemporaries weren’t anyway - they were designed to be very fast in regular service and the speed record was a by-product of that, but it wasn’t the sole reason for their existence). I’m not sure it would tell us much about the history and technology of locomotive development that we can’t already learn from historic locos (in some ways it might even detract from this history, as I hinted above) and I’m not sure what practical use it could be put to after the record-breaking attempt was done (whereas  Tornado/Sir Nigel Gresley/Flying Scotsman etc. have run in normal service both on the main line and on heritage railways and would be relevant static museum exhibits even when not operational).

[simon b]

The new build T1 is progressing nicely, and it will be roaming the rails at some point. The question is if there is anywhere suitable to run it at that sort of speed, the track will certainly take a pounding from it.

[rogerzilla]

The irony is that an A4 could almost certainly have gone faster than Mallard by the 1950s, when Kenneth Cook had sorted the middle big end problem and all of them had Kylchap front ends.  There was a gentlemens' agreement not to take the record away from Mallard, apparently.  The story goes that Alan Pegler told the driver of SNG to back off in 1959 when it got to 112mph and was still accelerating easily.

[simon b]

I have often wondered how fast the coronation class could actually go. I'm aware of the 114mph record, but after the modifications to their blastpipes and chimneys in 1939 performance was increased. So much so that two fireman would be required to keep up with the demand for coal. Could one of these given mallard a run for it's money?

[adb968008]

6 hours ago, rogerzilla said:

The irony is that an A4 could almost certainly have gone faster than Mallard by the 1950s, when Kenneth Cook had sorted the middle big end problem and all of them had Kylchap front ends.  There was a gentlemens' agreement not to take the record away from Mallard, apparently.  The story goes that Alan Pegler told the driver of SNG to back off in 1959 when it got to 112mph and was still accelerating easily.

I did Bitterns 90mph trip 10 years ago, what struck me wasnt the 90mph, but how easily it went from 75 to 90… it was a matter of a few seconds effort, the loco wasnt even straining. The second aspect was consistency, it was mid 70’s up and down hill, long range running, rather than short sprints of speed… the speed was averaging 75 for long periods, it was working in an unstressed zone, rather than flat out.

 

If left to accelerate it would have easily been a very good speed over the ton before Newark… and it had quite a  10 coch load behind it too. Having done 18201 and 01509 in Germany at higher speeds the difference was the acceleration was slower, despite lighter loads… they were working much harder to get there.

 

 

Edited December 27, 2023 by adb968008

[DenysW]

William Wiltun in "American Steam Locomotives" (Indiana University Press) has a long discussion on the 130-140 mph claims for the Pennsylvania duplexes. His view of the truth is that the speedos only went to 125 mph, and the reason the speed claims were (and are) made is that the poppet valves were an innovative design that had given many months of reliable operation at speeds up to 125 mph. But when they were put into 'normal' service they started failing in weeks. A paid-passenger was put onto the trains to see how they were actually run by timing them against mileposts (etc.). The conclusion from this was that 130-140 mph was routinely achieved downhill where the crews need to make up time having lost it uphill, and that this excessive speed was what was destroying the valves. This was good enough speed data (by averaging enough points to get rid of random errors) to be convincing for cause/effect but not enough to record-book entries.

 

FWIW, I've seen claims elsewhere that the Mallard dynamometer car trace was a very short blip and that, even downhill, the power needed to accelerate the train from just-before to just-during the record was no-way-possible. This is supported by an assertion that the speed record was not claimed until long after that actual 'braking trials'.

 

Overall, ahead of strict-comparison tests on a flat long straight section of track in a reasonably deep cutting (no sidewinds) and no points/crossovers, I feel that all steam speed records remain highly dubious. There's no agreement on what is a sensible load, whether light-engine counts, whether you should discount weather conditions that give more slippery rails, etc. etc. etc.

[Old Gringo]

DenysW,

 

Thanks for your interesting comment, which mentions one of the most informative books on the design and development of the steam locomotive between 1880 - 1960 ever produced - on either side of the Atlantic.

 

However, for those interested in searching out a copy, the author is William L. Withuhn (1941 - 2017) and the 452 page book is copyright Gail Withuhn, 2019, ISBN 978-0-253-039020.

 

After reading the book, there's so many more questions regarding "so, who's faster?"

[adb968008]

54 minutes ago, DenysW said:

 

 

FWIW, I've seen claims elsewhere that the Mallard dynamometer car trace was a very short blip and that, even downhill, the power needed to accelerate the train from just-before to just-during the record was no-way-possible. This is supported by an assertion that the speed record was not claimed until long after that actual 'braking trials'.

 

“Long after”…. Thats a myth definitely to be debunked..

Extract of newspaper, July 4th 1938.. 1 day after, and the article even says “yesterday”.

 

https://blog.britishnewspaperarchive.co.uk/2013/07/03/the-mallard-sets-a-new-uk-speed-record-for-steam-locomotives-3-july-1938/#:~:text='The Mallard' Sets a New,Steam Locomotives – 3 July 1938&text='The locomotive was drawing a,'

 

Perhaps the initial 125mph was the source of the myth, as 126mph needed to be authenticated after.

 

Edited December 27, 2023 by adb968008

[adb968008]

55 minutes ago, DenysW said:

The conclusion from this was that 130-140 mph was routinely achieved downhill where the crews need to make up time having lost it uphill, and that this excessive speed was what was destroying the valves. This was good enough speed data (by averaging enough points to get rid of random errors) to be convincing for cause/effect but not enough to record-book entries.

 

I call BS here too… 140mph routinely… we cant even do that on LWR track on conventional railways today… If there was route 140mph running several times a day on the much heavier and longer trains running in the US that track would have been giving way.

American steam certainly has the grunt, and marathon capabilities and can put a good turn of speed for sustainable periods, but i’d be sceptical of 130mph claims on anything but a very specific set of very occasional circumstances.

[Old Gringo]

23 minutes ago, adb968008 said:

I call BS here too… 140mph routinely… we cant even do that on LWR track on conventional railways today… If there was route 140mph running several times a day on the much heavier and longer trains running in the US that track would have been giving way.

American steam certainly has the grunt, and marathon capabilities and can put a good turn of speed for sustainable periods, but i’d be sceptical of 130mph claims on anything but a very specific set of very occasional circumstances.

 

Have you watched the video in the opening post all the way through?

And read the book quoted in DenysW's post?

Do you accept the figure quoted by the German locomotive (05.002) under test on level track?

[rogerzilla]

15 hours ago, adb968008 said:

“Long after”…. Thats a myth definitely to be debunked..

Extract of newspaper, July 4th 1938.. 1 day after, and the article even says “yesterday”.

 

https://blog.britishnewspaperarchive.co.uk/2013/07/03/the-mallard-sets-a-new-uk-speed-record-for-steam-locomotives-3-july-1938/#:~:text='The Mallard' Sets a New,Steam Locomotives – 3 July 1938&text='The locomotive was drawing a,'

 

Perhaps the initial 125mph was the source of the myth, as 126mph needed to be authenticated after.

 

Gresley was always satisfied to claim it as 125mph.  126mph was only achieved momentarily.  Mallard didn't get an optimal run down Stoke Bank; there was limited space to get the record between speed limits, which I don't think were always there.

Edited December 28, 2023 by rogerzilla

[DenysW]

15 hours ago, rogerzilla said:

Gresley was always satisfied to claim it as ...

One of the things I like about the Guiness Book of Records is that they try to have a defined set of parameters to judge new claimants against.

 

None of the steam speed records meet this criterion in a way that is transferrable to a new claim without proponents of the old claim saying "Yes, but ..."., or, as @adb968008 above, "I simply don't believe that is reliable evidence."