Imaginary Locomotives

[Zomboid]

Was the T1 not capable of higher speed than the F7, if not regularly scheduled as such?

[rockershovel]

Was the T1 not capable of higher speed than the F7, if not regularly scheduled as such?

Good question, on the evidence. It certainly doesn’t seem to have been as reliable.

Edited January 10, 2019 by rockershovel

[rockershovel]

Chapelon apparently believed that he could have got 16,000 hp out of a Big Boy, if he had been given the chance. I think that might be a bit optimistic (it would require something like 7.5 to 8 horsepower per pound of steam, the best ever achieved was a little over 11 hp/lb) but 11,000 to 12,000 hp should have been achieveable. The American railroads operated in an economic environment where it made more sense to build bigger versions of simple locomotives than to build smaller, more complicated ones. The exception seems to have been compounds, which only really found their niche in North America where they could run heavy trains at constant speeds for hours on end.

I wouldn’t call the S1 or T1’s “simple”

 

The Pennsylvania S1 was a state-of-the-art design with a boiler 99% the capacity of the Big Boy and rated to produce an extra 13% at the drawbar, nowhere near 11-12,000 hp

 

Churchward, Gresley and others copied American practice. I don’t see much evidence of the reverse being true. Mallard might have been the “fastest steam locomotive” but the design clearly couldn’t sustain the effort, or anything like it, for any length of time

Edited January 10, 2019 by rockershovel

[Corbs]

One wonders if out of the restrictions of the UK loading gauge, width was the biggest constraint.

 

Looking at American/European/Australian designs, they have less of a width restriction so can fit larger diameter cylinders. As far as I can tell the maximum outside cylinder size possible in the UK was about 21"?

 

American companies seemed not to like inside cylinders much, but they had the luxury of being able to have huge overhangs on the outside without clouting platform faces.

[The Johnster]

Was the T1 not capable of higher speed than the F7, if not regularly scheduled as such?

 

Allegedly, but the information is apparently taken from a speedometer reading, and given the propensity of these locos to slip even at high speed, has to be taken as suspect.  T1s are supposedly capable on paper of 140mph+.

[Bloodnok]

T1s are supposedly capable on paper of 140mph+.

And there's a group of people out there mad enough to try to build a new one. https://prrt1steamlocomotivetrust.org/ They are also mad enough to state they want to have a crack at the record ... so one day we might actually know what these machines will do.

[AlfaZagato]

And there's a group of people out there mad enough to try to build a new one. https://prrt1steamlocomotivetrust.org/ They are also mad enough to state they want to have a crack at the record ... so one day we might actually know what these machines will do.

 

I, sadly, highly doubt either the DOT or the FRA would even consider such an occurance.   Even with the forced acceptance of PTC, the DOT does not relax the 70mph speed limit in place on 90% or so of the US network.  The Texas HSR is being built to appropiate standards, and there is the Northeast Corridor, but the days of 100mph timings are long dead in the US.

 

If the new T1 is actually finished, the only chance I see of it being pushed to the limit would be if the Germans extended the same invite that they did to Tornado to the T1.    Or if the UP tells the DOT to shove it, and stages some race between 844 and the T1.

[The Johnster]

Indeed they are, Colonel.  Should the build be completed, it will of course suffer the same problems as the original, but they are hoping to use electronic monitors to detect wheelslip and some sort of feedback mechanism to restrict it.  

 

I am no engineer, but it seems probable to me that slipping is induced when the load on one set of coupled wheels exceeds that on the other, something that could occur as the loco distributes it's weight differently on the springs as it runs.  Effectively the entire load is suddenly dumped on the remaining set, which of course loses grip.  

 

But I think Mallard's record is safe for now, and the Germans will remain the owners of the current 'world's fastest' steam locomotive in 'normal' use.

 

I, sadly, highly doubt either the DOT or the FRA would even consider such an occurance.   Even with the forced acceptance of PTC, the DOT does not relax the 70mph speed limit in place on 90% or so of the US network.  The Texas HSR is being built to appropiate standards, and there is the Northeast Corridor, but the days of 100mph timings are long dead in the US.

 

If the new T1 is actually finished, the only chance I see of it being pushed to the limit would be if the Germans extended the same invite that they did to Tornado to the T1.    Or if the UP tells the DOT to shove it, and stages some race between 844 and the T1.

A T1 is well above the European loading gauge in terms of both height and width, and cannot run in Germany.  Probably not many places in Europe that can handle that sort of axle load, either!

Edited January 11, 2019 by The Johnster

[Zomboid]

I'm pretty sure the T1 will be completed. Whether it'll get a chance to have a go at the record is another thing, but where there's a will there's a way, and the NEC is already home to 150mph running.

[melmerby]

I'm pretty sure the T1 will be completed. Whether it'll get a chance to have a go at the record is another thing, but where there's a will there's a way, and the NEC is already home to 150mph running.

And some close to 100mph station - station timings

 

Keith

[Budgie]

I, sadly, highly doubt either the DOT or the FRA would even consider such an occurance.

If it can't run in the US, could it run in Mexico, or central or south America?

[rodent279]

A1 in Germany? Did they decline the offer?

[AlfaZagato]

If it can't run in the US, could it run in Mexico, or central or south America?

 

I never said it couldn't run.   Depending on the railroad, we do have vintage equipment running.    It's a matter of high-speed running.    The USA's infrastructure is disintegrating as a whole, and our signaling is woefully underwhelming.    I don't think the Mexican system, or any of the South American systems, can handle a locomotive as long as the T1.   My knowledge is such that the Latin-American systems are very mountainous in general.

[34theletterbetweenB&D]

Regarding the GN Pacific, why not use a trapezoidal grate, the front fits between the frames and the rear widens out over the frames, used by the French...

 But that was only invented in 1906, and then allow ten years lag for UK sensibilities toward all foolish / speculative design improvements to be overcome, and then we are in the middle of WWI and this is no time to be experimenting...

 

I would tend to dispute that steam was brought to the ultimate here.    Yes, we had massive, extremely powerful locomotives... 

 Which worked, and for all their inefficiency reliably produced the highest sustained power outputs ever seen from steam locos. They could have stood technical improvement, but were nevertheless simply WOW!  

 

One wonders if out of the restrictions of the UK loading gauge, width was the biggest constraint...

 In the opinion of St. Andre Chapelon - may his opinions always be respected - axle load was the most serious constraint on European maximum power steam development, UK included.

[rockershovel]

Axle load was undoubtedly a restraint, but the U.K. loading gauge was and is, significantly smaller than any Continental one - hence the inclined cylinders on the BR “Standards”

[rockershovel]

Allegedly, but the information is apparently taken from a speedometer reading, and given the propensity of these locos to slip even at high speed, has to be taken as suspect.  T1s are supposedly capable on paper of 140mph+.

Surely a GPS speedometer, possibly in conjunction with laser speed measurement would put this beyond doubt, regardless of wheelslip?

[john new]

Surely a GPS speedometer, possibly in conjunction with laser speed measurement would put this beyond doubt, regardless of wheelslip?

It would for a current run but not for the historic records if those were from a speedo reading. A bit like back in the day when as stupid teenagers we raced cars and bikes to do the ton, the dial said we did but I bet high 80s was probably what we actually got. Much of the argument about records, (even Mallard's actual rather than claimed) is about accuracy in the recorder/recording equipment's data.

 

City of Truro, ridiculously fast for the day, but stop watch timed. Mallard, modern analysis is again confirming it went beepingly fast but probably 1 to 2 mph less than stated. Bill Hoole IIRC wrote about taking an A4 into a high speed situation where it's physical feel was like he'd never experienced before, who knows what that record might have been as he ran very fast regularly so it must have been an exceptionally fast run even for him.

Edited January 11, 2019 by john new

[The Johnster]

The best accuracy is obtained by timing the train (or car, or whatever it is) over a measured distance; I doubt that GPS, which is I believe only accurate to about 2 metres at best, could give more than a fairly accurate average speed.  And you need a backup and 'control' measurement of calibrated instruments; remember that City of Truro's alleged record was independently timed by two observers, Charles Rous-Marten (who was very experienced in such matters), and the GPO inspector on the train, and their records verified each other.  Despite this the record was never officially accepted.

 

Only 2 years later, a test run of the brand new 2904 Lady of Lyons was recorded at 135mph light engine, largely discounted by any serious writers but none of them were on the loco.  This was timed over a known distance between two signalboxs, Little Somerford and Hullavington, on clocks that were 'calibrated' by a time signal every morning.  The affair very nearly ended badly as the loco had difficulty pulling up for a signal against it protecting the junction at Wootton Bassett (not Royal in those days) and they only got away with it by the signal clearing in time.  

 

This adventure did not reflect particularly well on the professionalism (or wisdom) of some of the people involved on the footplate, who included some big Swindon names, and was not publicised, so it is very difficult at this remove of time to be precise about what actually happened.  Apparently the whole thing was done for a bet, and Churchward was livid when he found out!

[The Johnster]

The best accuracy is obtained by timing the train (or car, or whatever it is) over a measured distance; I doubt that GPS, which is I believe only accurate to about 2 metres at best, could give more than a fairly accurate average speed.  And you need a backup and 'control' measurement of calibrated instruments; remember that City of Truro's alleged record was independently timed by two observers, Charles Rous-Marten (who was very experienced in such matters), and the GPO inspector on the train, and their records verified each other.  Despite this the record was never officially accepted.

 

Only 2 years later, a test run of the brand new 2904 Lady of Lyons was recorded at 135mph light engine on the then still new Badminton cut-off, largely discounted by any serious writers but none of them were on the loco.  This was timed over a known distance between two signalboxs, Little Somerford and Hullavington, on clocks that were 'calibrated' by a time signal every morning.  The affair very nearly ended badly as the loco had difficulty pulling up for a signal against it protecting the junction at Wootton Bassett (not Royal in those days) and they only got away with it by the signal clearing in time.  

 

This adventure did not reflect particularly well on the professionalism (or wisdom) of some of the people involved on the footplate, who included some big Swindon names, and was not publicised and rather hushed up, so it is very difficult at this remove of time to be precise about what actually happened.  Apparently the whole thing was done for a bet, and Churchward was livid when he found out!

Edited January 12, 2019 by The Johnster

[Niels]

 

 

Only 2 years later, a test run of the brand new 2904 Lady of Lyons was recorded at 135mph light engine on the then still new Badminton cut-off, largely discounted by any serious writers but none of them were on the loco. 

 

Only problem is that Saints were balanced in a way where wheels would lift at about 100 mph.

 

https://www.national-preservation.com/threads/saint-class-135-ish-mph.923959/page-13#post-1815992

Edited January 13, 2019 by Niels

[Compound2632]

The best accuracy is obtained by timing the train (or car, or whatever it is) over a measured distance; I doubt that GPS, which is I believe only accurate to about 2 metres at best, could give more than a fairly accurate average speed.  And you need a backup and 'control' measurement of calibrated instruments; remember that City of Truro's alleged record was independently timed by two observers, Charles Rous-Marten (who was very experienced in such matters), and the GPO inspector on the train, and their records verified each other.  Despite this the record was never officially accepted.

 

Only 2 years later, a test run of the brand new 2904 Lady of Lyons was recorded at 135mph light engine on the then still new Badminton cut-off, largely discounted by any serious writers but none of them were on the loco.  This was timed over a known distance between two signalboxs, Little Somerford and Hullavington, on clocks that were 'calibrated' by a time signal every morning.  The affair very nearly ended badly as the loco had difficulty pulling up for a signal against it protecting the junction at Wootton Bassett (not Royal in those days) and they only got away with it by the signal clearing in time.  

 

This adventure did not reflect particularly well on the professionalism (or wisdom) of some of the people involved on the footplate, who included some big Swindon names, and was not publicised and rather hushed up, so it is very difficult at this remove of time to be precise about what actually happened.  Apparently the whole thing was done for a bet, and Churchward was livid when he found out!

 

I read back in the linked thread to get at the origin of the Lady of Lyons story - there does seem to be a kernel of truth in it (i.e. a high-speed light engine test run) but the data seems to have rather large uncertainties - signal box passing times recorded to the nearest 30s - at two miles a minute with boxes spaced just a few miles apart. Charles Rous-Martin's data is bad enough, with quarter-miles recorded to the nearest 0.2s.

 

I've never heard of the GPO inspector's data for City of Truro's run - where has this been published or discussed?

Edited January 12, 2019 by Compound2632

[The Johnster]

The GPO inspector timed the train and it was his data that was used in the press the following day; Rous Marten had been requested to withhold his report, eventually published some time later in 'Railway Magazine', by the GW, who were not pleased when the cat got out of the bag.  The competition between them and the LSWR for Plymouth boat traffic was fierce and there were claims of passengers tipping LSW drivers for early arrivals in Waterloo.  The GW's reticence was well advised, as there was a bad speeding accident a few weeks later at Salisbury involving a boat train derailing on the sharp curve at the London end of the station, which did not reflect well on the LSW's ability to curb it's drivers' enthusiasm.

 

It is my view, FWIW, that these events and the 'Lyons' incident, which could have had much more serious consequences at Wootton Bassett, soured the attitude of the GW towards 'speed records' and that sort of publicity, and they consequently focussed on high average timetabled speeds, publicising the 'Cheltenham Flyer' relentlessly in the inter-war period.  This may have had an influence on loco design and the 'what we've got is good enough and doesn't need improving' attitude.

 

I have no doubt that the 'Lyons' incident took place though even basic details were suppressed for many years, though what the actual speed attained was is debatable.  They went fast for sure, and would not have been able to pull up at Wootton's up Badminton home had they needed to.  Everybody was thoroughly ashamed of themselves, and rightly so to; had they run into the back of the up Bristol road train that preceded them at Wootton several notable later careers would have been terminated, if not by the accident by dismissal!

[34theletterbetweenB&D]

... Mallard, modern analysis is again confirming it went beepingly fast but probably 1 to 2 mph less than stated. Bill Hoole IIRC wrote about taking an A4 into a high speed situation where it's physical feel was like he'd never experienced before, who knows what that record might have been as he ran very fast regularly so it must have been an exceptionally fast run even for him.

 It is striking that all the maxima which are credible for steam locos in Germany, UK and US, are in the same 125mph/200kph zone. The direct reciprocating drive causes all sorts of resonances, and if one falls around 4Hz, the human jelly bags on the footplate will be wobbling along in sympathy, causing among other significant events vision disturbance. I have experienced this in a flight simulator, and it is acutely disturbing. (The steam loco that could do more would be a turbine - with a suitable gear ratio.)

 

...the brand new 2904 Lady of Lyons was recorded at 135mph light engine...

 Fake news. Along with the claim for CoT. ( Look at the discontinuity in the curve when Rous-Marten's data is plotted.)

[Gibbo675]

 It is striking that all the maxima which are credible for steam locos in Germany, UK and US, are in the same 125mph/200kph zone. The direct reciprocating drive causes all sorts of resonances, and if one falls around 4Hz, the human jelly bags on the footplate will be wobbling along in sympathy, causing among other significant events vision disturbance. I have experienced this in a flight simulator, and it is acutely disturbing. (The steam loco that could do more would be a turbine - with a suitable gear ratio.)

 

Hi 34 ... B&D,

 

You are correct about vision disturbance while upon steam locomotive footplates. There are certain combinations of speed and cut off, both under power and while drifting, that cause resonant effect of the vision.

 

It can be quite disconcerting to trying to work out if you can see a single or a double yellow, especially in the dark. Double greens don't exist and so are obvious, should you be approaching a double red then you are in trouble !

 

Gibbo.

[Ohmisterporter]

The best accuracy is obtained by timing the train (or car, or whatever it is) over a measured distance; I doubt that GPS, which is I believe only accurate to about 2 metres at best, could give more than a fairly accurate average speed.  And you need a backup and 'control' measurement of calibrated instruments; remember that City of Truro's alleged record was independently timed by two observers, Charles Rous-Marten (who was very experienced in such matters), and the GPO inspector on the train, and their records verified each other.  Despite this the record was never officially accepted.

 

Only 2 years later, a test run of the brand new 2904 Lady of Lyons was recorded at 135mph light engine on the then still new Badminton cut-off, largely discounted by any serious writers but none of them were on the loco.  This was timed over a known distance between two signalboxs, Little Somerford and Hullavington, on clocks that were 'calibrated' by a time signal every morning.  The affair very nearly ended badly as the loco had difficulty pulling up for a signal against it protecting the junction at Wootton Bassett (not Royal in those days) and they only got away with it by the signal clearing in time.  

 

This adventure did not reflect particularly well on the professionalism (or wisdom) of some of the people involved on the footplate, who included some big Swindon names, and was not publicised and rather hushed up, so it is very difficult at this remove of time to be precise about what actually happened.  Apparently the whole thing was done for a bet, and Churchward was livid when he found out!

 

I wonder how safe the people on the footplate would be considering the GWR did not have doors between engine and tender? Are there any instances of people falling off the footplate through lack of doors?