Sir Nigel Gresley - The L.N.E.R.’s First C.M.E.

So the figures we have above need to be taken with a pinch of salt. These are tests in relation to the configuration of a train (loco plus coaches) and optimising the full streamlining of said train. These tests conducted are not the same as those which were conducted to produce the version of the water tube boiler W1 that we now know today.

So there's a few things to take away here:

• The W1 was superior in terms of streamlining to the conventional locomotive
• Any gains on the locomotive were outweighed by the fact that it was at the cab end narrower than the width of the tender, identical to 4472's
• This issue creates additional areas of drag by way of air passing onto the slightly more exposed tender

The W1 as a locomotive would have been better overall had either one of two things been done:

• Cab width increased to match or was made greater than its tender's width
• the tender was modified and brought into line with the profile of the locomotive ahead of it

But interestingly:

• gains in terms of streamlining are wiped out by pulling coaches of "bad aerodynamic form"

This means the Silver Jubilee and Coronation sets when paired with the A4s were probably optimal shapes for the day in terms of streamlining.

This checks with modern principles for train aerodynamics, as I am discovering in the reading of some textbooks for high speed train design.

Fascinating stuff. So on a first glance, you think the W1 itself is bad aerodynamically, but it's actually the opposite: it has good streamlining, but when it was being developed, earlier than the full understanding Johannsen has here, the standard type tender and the drag that would emerge was not thought of.

Weirdly the flat fronted cab of 4472 actually helps with the overall streamlining by way of reducing drag on the tender!

But perhaps more important than just the loco and tender - the stock has to be optimised to streamlined form to match.

Truly a scientific art form!

 

I think the point is made that it isn’t desirable, and that when the W1 was built streamlining and wind tunnel testing was in its infancy.

This - if you like - error - means that the gains on the loco were outweighed by the drag on the tender. Not desirable at all. But a fascinating part of the design process.

It explains why the W1 cab design was never used again on anything else, but elements of the front end were in later work.

But we are talking in scale form, 1/12.

 

It does make we wonder how seriously railway aerodynamics was applied in the 1930's - it was good enough to get planes to 400mph, or whether streamlining was more for appearances sake ...

 

By the LMS and LNER, really seriously. They co-operated on a lot of testing. Much of the initial work was done on the W1, the LMS took up the baton in the early 30s and the LNER worked with them, through Frederick Johannsen.

Tim Hillier-Graves has passed me Johannsen's archive for study and it's absolutely fascinating. The one which stands out to me is how close the original LMS ideas were to the German class 05 design.

 

Those figures only seem to apply to Engine and Tender, so a smaller tender may act like a sort of boat-tail when purely measuring the models without carriages.

A large blunt ended tender that matches the coaches would probably prove better aerodynamically when coupled to carriages than one that lowers the drag when running light engine.

 

The tests have a mixture of engine, engine and tender, engine and tender and a set number of coaches, coaches with modifications to the gap and or valances attached. It’s really fascinating stuff.

The thing to take into account is that these are some of the earliest tests and designs for streamlined or aerodynamically improved forms of train.

The W1 is a case in point: it does some things well, others less well. It wasn’t actually far away from being optimised for drag reduction and that’s the incredible thing about it.

Wind tunnel testing was in its infancy and Gresley and his team made something that was actually rather good at what it was supposed to do. Had they fitted a tender like the A4s received (smoothed fairings, no beading, straight sides to match the coach widths), I think we’d have seen a much better result.

I’ve got a much greater respect for the LMS testing too. Having seen the photographs of their testing it’s pretty clear that writers claiming the streamlining on the coronations was a hastily added thing don’t have all the primary evidence to hand. It really was scientific and applied well.

Clearly and fundamentally inspired by Wagner’s work for the Nazis, mind. The 05 class loco was studied very heavily it seems, and some of the tests done by the Germans are quoted by Johannsen.

 

I agree, we have had push back, some of it very well reasoned and has made me question my take on things.

I think that's because, so far as my research goes, most of Gresley's work is pretty non contentious. Even with the Use of Engine Power document, I think there's a huge amount of merit in Gresley's approach and would argue strongly that the issues we came to see later in terms of lack of standardisation isn't necessarily entirely down to him.

It's a good question and I think, for my part, I see Gresley as one of Britain's greatest locomotive engineers, if not (whisper it!) the greatest. He was so ahead of his time on so many different parts of railway engineering, and a lot of recognition for his scientific approach to resolving complex engineering problems has gone unrecognised I feel.

At the same time I can recognise that by 1941 a change of approach was needed on the L.N.E.R. and Gresley may not have been capable of making the changes required, for a variety of reasons. There's no shame in that, actually, it just means that Gresley was human.

Thompson was right in what he did that followed, but in saying that it doesn't mean that Gresley was wrong to plough his own furrow in the first place.

There's an element of football team ness to a lot of the secondary evidence where the L.N.E.R. is concerned and I can only think that it's because some of those secondary sources don't have the necessary research skills or background to recognise or appreciate elements of the full story.

There are of course some exemplary writers too and we should be grateful to Hardy (Richard and Andrew!), Grafton, Townend, Hillier-Graves, Brown and similar for their work that has shone a light on Gresley's engineering work.

 

I suggest that in the case of most CME's its how they played the hand they were given.

Collett, Stanier & Gresley all had different solutions to the needs of different railways

I am not sure that many could be described as 'Bad'

 

Completely agree.

 

SAC Martin noted

At the same time I can recognise that by 1941 a change of approach was needed on the L.N.E.R. and Gresley may not have been capable of making the changes required, for a variety of reasons. There's no shame in that, actually, it just means that Gresley was human.

Thompson was right in what he did that followed, but in saying that it doesn't mean that Gresley was wrong to plough his own furrow in the first place.

It does mean, however, that Thompson was limited in his actions by the decisions taken by Gresley as to change direction too quickly would have come at a cost and time that was not available due to wartime constraints. Those same constraints may have restricted Gresley (e.g. potential electrification of the ECML once the GCR scheme had been completed) hence confirming that both Gresley and Thompson were constrained by external (LNER Board) forces and not simply reluctance to impose their respective "furrows" in the first place.

 

I imagine most CME's would have been constrained by the products of their predecessors and/or their board of directors. I can think of four that this didn't seem to apply to - Brunel, Churchward, Stanier and Bulleid. All esteemed engineers that were given a relatively free reign with the company's coffers and produced the odd "lemon". Of these I would suggest that Churchward was the most effective. In Brunel's case it was an extremely expensive broad-gauge dead-end, despite of which he is revered by some (rightly?) as Britain's greatest engineer. Perhaps they were also accomplished salesmen?
In the context of what they inherited, Gresley and Thompson must also have been good at "selling" their programmes to the board.

 

I suggest that Bulleid could have benefitted from some better management by the Southern board.

 

Engineer had a slightly different context in Brunel’s day, “Civil” being the primary context snd “mechanical” very much in its infancy. Brunel I’d suggest was a visionary in business terms (for want of a better descriptor) and clearly a very talented civil engineer; as a mechanical engineer the less said the better. But two out of three ain’t bad. (Of course, it’s not unknown for business visionaries to lose their backers plenty of money as well!)

Tom

 

You are missing of course Maunsell, who I’d suggest bears comparison with those three, and I’d suggest was more innovative than Collett, and collectively (across a body of work) far more successful than Stanier, who I’d suggest had rather too many misses to be considered in the front echelon.

Tom

 

But he did have some pretty big hits in the Black fives, 8Fs and Duchesses and arguably only the class 3 tanks as definite failures. And if you swap Stoke Bank for the hill going down to Crewe, who knows? Oh for a run down Stoke behind 46257.

I'd vote for Churchward, Gresley and Stanier from the 20th century.

 

And yet in terms of workshop practice and manufacturing methods Collett was surely by a distance the most innovative.

 

I'm wary of Stanier because - although his designs were both different and promulgated by those who followed (i.e. Fairburn and Riddles) it could be said that he simply added to GWR practice on a railway where he was given leeway to do so. IMHO his Princess Royal class was simply a Pacific version of the GWR Castles that Swindon never allowed and the Duchesses were simply an improved version of the Princesses. His Black 5 success was based on the GWR Halls; his 8F success was based on the GWR 28xx and his Jubilees were a 3-cylinder version of the Black 5. His fame with the Royal Scots was the simple application of an improved boiler on an existing chassis as was the later application to the Patriots initiated by experiments with the pair of Jubilees. Agreed that the successes were such that further conversions / upgrades were approved by both Fairburn and Ivatt.
Agreed that Churchward and Gresley deserve their nomination because the did not simply follow trends but initiated trends that others followed hence their success was based on their personal initiatives; Stanier I venture to suggest simply used existing practice to better effect.

 

But that analysis is of the drawing office variety. It disregards the very considerable achievement of taking a diverse inheritance and consolidating it into a relatively small number of highly effective designs, even if those designs had tricky introductions.

And that, in return, brings us back to the question of what a CME was for.


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