If The Pilot Scheme Hadn't Been Botched..........

[Titan]

On 05/11/2021 at 15:55, Traintresta said:

I was discussing this topic with my old man, who suggested BR would have done better to design and build its own locos in house, using the best bits of what was available, in much the same way they did with the class 56 and HST. 

 

 

The class 24,25,44,45,46 were all designed and built in house by BR using well proven Sulzer units, although some class 25 construction was contracted out to Beyer Peacock whose build quality was superior to that of BR.

Edited November 7, 2021 by Titan

[Pandora]

2 hours ago, Titan said:

 

The class 24,25,44,45,46 were all designed and built in house by BR using well proven Sulzer units, although some class 25 construction was contracted out to Beyer Peacock whose build quality was superior to that of BR.

From 1948 BR Workshops carried on as before, repairing the run down stock using the tried and tested methods for which they were so familiar, modernisation in the change over to constructing small batches of diesels may  have rocked the boat and the  crew overboard,  Private Industry were the ones to take on diesels, and they could take the risks and blame if the goods delivered were not suitable. Recall that  nearly 2500 steam locomotives built by  or for BR after  nationalisation, only 999 were the Standards, the remainder Company designs such as the A1 class and the Castle class, the BTC did not formulate a much of Traction Plan,  Bonavia was very critical of this , he raised the matter with the BTC and made no progress, his conclusion of the Motive Power Committee  being only  a paper exercise,  these paths confirm  the major content of this interesting and popular  thread which has brought many facts and history before  us,  the Pilot Scheme was indeed  a botch, a mad scramble, of wasted opportunity and too late.

Edited November 7, 2021 by Pandora

[rockershovel]

11 hours ago, Pandora said:

Those GM/EMD Art-Deco  or Streamline-Moderne  E and F units are one of my interests, E units were 1800 hp, "E for eighteen",  F units 1400hp  "F for fourteen", to work heavy trains over their famous  gradients ,  ascents for up to 2 hours at a stretch, certain railroads allocated  4 F units over 3 E units for the benefit of 16 weight bearing motored axles over 12.

That's a general comment on US engineering - favouring reliability over power output, and easy maintenance over durability. Few US steam locos achieved the very long working lives common over here, and the diesels were the same. 

 

Their cars and motorcycles were the same. I know someone who has ridden a 45" sidevalve Harley Davidson for over forty years, racking up around 200,000 miles BUT the engine requires a full rebuild after around 20,000 miles, a top end rebuild around 10,000. However the bike is like grandfather's axe, engineered to be rebuilt almost indefinitely provided that the main castings remain intact and I doubt that much remains of the original mechanical parts by now. 

[cheesysmith]

You also have to remember the USA diesel locos were very conservative in the HP outputs. Whilst we had the rats with 1250hp Sulzer units, the same GM engine used in Ireland was only 950hp (?IIRC). Also, GM was only interested in suppling full locos, and only later went down the route of local partners, but too late for the modernisation plan. Which was a pity, as if GM had got their foot in the door, the 56 could have been the loco that set the standard for freight for the next 20 years, in the shape if the SD40-2.

 

(The 59 was actually based on the SD50, without the uprated unreliable engine).

[peach james]

10 hours ago, cheesysmith said:

You also have to remember the USA diesel locos were very conservative in the HP outputs. Whilst we had the rats with 1250hp Sulzer units, the same GM engine used in Ireland was only 950hp (?IIRC). Also, GM was only interested in suppling full locos, and only later went down the route of local partners, but too late for the modernisation plan. Which was a pity, as if GM had got their foot in the door, the 56 could have been the loco that set the standard for freight for the next 20 years, in the shape if the SD40-2.

 

(The 59 was actually based on the SD50, without the uprated unreliable engine).

How then do you explain the 'stralian diesels?  https://en.wikipedia.org/wiki/Victorian_Railways_B_class_(diesel) as a start...

GMD was not just interested in supplying CKD loco kits

BUT, they still wanted $ not PS...

James

[cheesysmith]

2 hours ago, peach james said:

How then do you explain the 'stralian diesels?  https://en.wikipedia.org/wiki/Victorian_Railways_B_class_(diesel) as a start...

GMD was not just interested in supplying CKD loco kits

BUT, they still wanted $ not PS...

James

 

All the "value" bits are EMD, with a locally built body. UK was on a export drive and BR would not been allowed such a loco. If they had partnered a UK company and just provided the engines, things might have been different. Also, about the same hp as a 33 for 115 tons? But looking at how long they survived, can anybody else see them as the AU class 37?

[peach james]

What else are you going to get?  GMDD as it was, is going to want to sell the traction motor/generator/diesel engine & control package, and probably the trucks as well.  As has been pointed out up thread, that's about 2/3rds the price of the loco.  I'm unsure if GMDD would have established a shadow factory in the UK to assemble the bits in the UK, similar to GMD (London, Canada), but had fair sized contracts (like the ~850 or so 47's) been in the offering, I suspect they would have.  That being said, if you look at how a GMD diesel is built, the value added was not by GMDD but by the sub contractors who actually made things for GMDD.  

Saying that GMDD was uninterested in local partners is clearly not true.  Equally, saying that the Exchequer would not allow the purchase in of 2/3rds the value of locomotives is true- there wasn't the currency or gold to allow for it.  So, it is a moot point- GMDD could not supply because they weren't going to build the complete supply chain within the UK to duplicate what existed in the USA.  Instead BR got the pilot scheme diesels, then the pilot scheme was thrown out just like it had thrown out the modernization plan, and large amounts of labour were used to build DE's and DH's that were unfit for the task, and/or had the task disappear as they were being built.  Some of this is hindsight being 20/20, but a lot of this is easy to predict at the time.  What we really needed was a mass production of Fells  (or perhaps Hunslet Steam/Diesel engines...)

James

 

[Flying Pig]

2 hours ago, peach james said:

What we really needed was a mass production of Fells  (or perhaps Hunslet Steam/Diesel engines...)

 

Are you thinking of the Kitson-Still locomotive?  

[peach james]

Yes, sorry, thought it was Hunslet rather thank Kitson.  A remarkably questionable piece of engineering, at any rate !

 

[Traintresta]

Interesting proposal from

the LMS Fairburn era powered by a 16SVT rated at 1600hp. 
 

It’s the same weight as a 31with more power and a similar wheel configuration in that there are 4 powered axles and 2 carrying axles. 

[Pandora]

Please post the title and author of the book, I wish to buy a copy

[russ p]

On 12/11/2021 at 12:21, Traintresta said:

Interesting proposal from

the LMS Fairburn era powered by a 16SVT rated at 1600hp. 
 

It’s the same weight as a 31with more power and a similar wheel configuration in that there are 4 powered axles and 2 carrying axles. 

 

What was the British obsession with weird wheel arrangements when surely it was proved more that ten years earlier in the US that a pair of bogies were the way forward 

[cheesysmith]

On of the most powerful US locos, ran at high speeds, hauled heavy freights, and had a good life, used two cast steam type chassis mounted under the body. It was two 4-6-0 chassis back to back, coupled together with a pivot and had a short term power rating of 8500hp. This was the GG1.

 

If they could have built it with 50hz motors, and squeezed it to the BR gauge, even the mass of it would have been allowed, as each have was less then some of the Pacific's.

[Titan]

22 minutes ago, cheesysmith said:

On of the most powerful US locos, ran at high speeds, hauled heavy freights, and had a good life, used two cast steam type chassis mounted under the body. It was two 4-6-0 chassis back to back, coupled together with a pivot and had a short term power rating of 8500hp. This was the GG1.

 

If they could have built it with 50hz motors, and squeezed it to the BR gauge, even the mass of it would have been allowed, as each have was less then some of the Pacific's.

 

In other words, the GG1 used the same arrangement  on UK locos but with extra axles, - like the two 0-4-0 chassis back to back of the class 76, or the 2-6-0 chassis of the class 40/peaks which took traction/buffing loads if not actually coupled.  The GG1 has much more in common with British practice, far from an unusual arrangement, and is nothing like the LMS example above - it isn't even a diesel loco!

Edited November 14, 2021 by Titan

[russ p]

The US also had the centipedes but these were actually two  4-8-0 bogies for want of a better description 

Edited November 15, 2021 by russ p

[rockershovel]

3 hours ago, cheesysmith said:

On of the most powerful US locos, ran at high speeds, hauled heavy freights, and had a good life, used two cast steam type chassis mounted under the body. It was two 4-6-0 chassis back to back, coupled together with a pivot and had a short term power rating of 8500hp. This was the GG1.

 

If they could have built it with 50hz motors, and squeezed it to the BR gauge, even the mass of it would have been allowed, as each have was less then some of the Pacific's.

How, exactly was the GG1 articulated? It surely didn't have two six-coupled chassis fixed in a single rigid frame?

[Nearholmer]

From Hinde & Hinde 1948.

 

 

Irritatingly, they give a really good sectional elevation and plan of the body, but not the running gear!

 

But, they do give this photo of the running gear of a slightly later New Haven loco that was, I’m pretty sure, substantially the same, and certainly shows the principles.

 

 

Edited November 14, 2021 by Nearholmer

[Nearholmer]

Getting back to the “weird wheel arrangements” question: a lot of this was driven by traction motor sizes, in that, in the early days, a loco with motors above a certain rating became difficult/impossible to construct using axle-hung, nose-suspended motors within conventional bogies. That implied either lots of ‘small’ motors spread among many axles in a rigid frame (centipedes)  or fewer big motors plus yoke or Jack shaft drive. There was lively debate about whether it was best to use one big motor, or two or three smaller ones, even on small locos, hence the single-motor with Jack-shaft drive vs two a-h, n-s motors comparison in the LMS shunter programme.

 

That LMS loco design may have “maximum traction” bogies on the outer ends. These were a tramcar technology that was designed to alter weight distribution under load. But, I suspect not, because of where the pivot-point is. More likely that they hadn’t hit on the idea of a 1-Bo bogie yet, or were doodling away looking at multiple options, and this iteration happens to have made it into a modern book.

 

The dynamics of all these various wheel arrangements were quite a puzzle to all concerned too. The first really serious book on the subject was F W Carter “Railway Electric Traction” 1922, a good third of which is full of formulae and diagrams about rail-wheel dynamics, and which remained ‘state of the art’ until probably the late-1960s. One can imagine the LMS designers and/or their potential suppliers poring over that and trying to decide which arrangement would destroy the track least quickly.

 

 

 

 

 

Edited November 14, 2021 by Nearholmer

[cheesysmith]

The interesting thing is that proposed diesel is just the same as what was proposed for the 10000, 4 motors over 6 axles. It was later changed to using 6 motors. The Bo Bo Bo arrangement has been used successfully in Europe and by Eurotunnel, but is favoured where there is curving restrictions.

 

As a aside, the PA electrics, with the steam age chassis, keep me thinking what would the GC have been like if electrified earlier. Express locos with 4-4-4, mixed traffic 4-6-4, heavy freight 2-8-2. The early PA were actually box cab locos with the cabs at the outer ends, a box type body on top of steam cast chassis with motors fitted to the driving wheels.

[Traintresta]

On 14/11/2021 at 05:11, Pandora said:

Please post the title and author of the book, I wish to buy a copy

English Electric main line diesel locomotives of British Rail by Brian Webb, part of the Davis & Charles locomotive studies series. 

[Traintresta]

On 14/11/2021 at 09:27, russ p said:

 

What was the British obsession with weird wheel arrangements when surely it was proved more that ten years earlier in the US that a pair of bogies were the way forward 

It wasn’t just a British obsession. The Japanese and Americans had lots of electrics using similar wheel arrangements and I’m pretty sure there were a good many locomotives like that in Europe to. Parts of the commonwealth had plenty as exported by British companies. The proliferation of them suggests they either had a valid application to

overcome some engineering problem or they were all that was known at the time. We know the latter isn’t the case so there must have been a valid engineering reason for them. 
 

I notice the electrics tend toward the 4 wheel leading bogie so I’m guessing that was a speed related thing, in much the same way 4-6-0’s and 4-6-2’s are considered to run smoother than 2-6-0’s and 2-6-2’s at speed. 

[Fat Controller]

11 minutes ago, Traintresta said:

It wasn’t just a British obsession. The Japanese and Americans had lots of electrics using similar wheel arrangements and I’m pretty sure there were a good many locomotives like that in Europe to. Parts of the commonwealth had plenty as exported by British companies. The proliferation of them suggests they either had a valid application to

overcome some engineering problem or they were all that was known at the time. We know the latter isn’t the case so there must have been a valid engineering reason for them. 
 

I notice the electrics tend toward the 4 wheel leading bogie so I’m guessing that was a speed related thing, in much the same way 4-6-0’s and 4-6-2’s are considered to run smoother than 2-6-0’s and 2-6-2’s at speed. 

If you're interested in some of the curious wheel arrangements, have a look here:-

https://second.wiki/wiki/liste_der_elektrolokomotiven_der_maurienne-strecke. Some lasted into the 1970s.

[Artless Bodger]

Perhaps a reason for the leading bogies on Maurienne locomotives was to carry the 3rd rail pick up shoes? Iirc this was a protected top contact 3rd rail. Mounting shoes from a rod drive loco with large-ish drivers migh be awkward, also mounting the shoes on bogies at the extremes would spread the contact avoiding gapping.

 

Austria (1570), Germany (E16, E17, E18, E19) and Switzerland used locos with a single leading axle, the BBO 1570 class was a 1A-Bo-A1 for express duties, SBB had the Ae3/6 and Ae4/7 designs with a single leading axle in one direction, the bogie was iirc at the end with the steam heating boiler, similarly some early German designs (E36). Drawings show the motors in the Ae4/7 were quite large, as noted above, too big for bogie mounting (though later Fench electric and diesel electric designs used monomotor bogies).

[Steven B]

Interesting ideas.

 

As much as I love them, the class 20 is a bit of an odd one out. Rarely used on it's own, it probably best thought of as a 2000hp machine with a 20t axle loading. A more powerful, go more places version of a class 37.

 

I'm not sure what the benefits are of having more than one of each power classification. What would a class 27 offer the ScR that a 25 wouldn't? Likewise a class 33 compared to a 37.

 

I'd seen the need for different levels of loco tractive effort, axle weight, gearing, top speed etc for a given horse-power but would think it could be achieved with the same basic body shell & engine within each power bracket. How much commonality could be achieved by adding additional cylinders to the same basic engine block?

 

Doing it properly you'd also have identical cab designs (inside and out) for each of maintenance and traction knowledge. Efficient but not overly interesting to model!

 

Steven B.

[Bittern]

I'm not sure if it's fair to blame BR for not thinking of standardising cab designs before the AL loco order, but not insisting on compatible MU systems was a big mistake, especially as the Southern had already demonstrated the benefits of a large compatible fleet and the transition to the new EPB system was already underway before the Blue Star classes were ordered. There would still have been a need for Blue Square for DMMUs, but that would still have been an improvement.