Midland Railway Company

[Edwardian]

So, what you seems to be saying is that these small engines could go downhill at least as fast as large engines. That doesn't seem to make them any bigger, however.

[John-Miles]

The speed attained by the Compound is interesting. It was a reasonably lengthy train and therefore the drag caused by air resistance/ friction would be appreciable. There would also be a drag effect on the front of the train. Drag and friction increase as a square of the velocity and at the same time engine power decreases with speed due to internal resistance factors. So attaining a speed in the 90s is a major achievment.

[Compound2632]

6 minutes ago, John-Miles said:

The speed attained by the Compound is interesting. It was a reasonably lengthy train and therefore the drag caused by air resistance/ friction would be appreciable. There would also be a drag effect on the front of the train. Drag and friction increase as a square of the velocity and at the same time engine power decreases with speed due to internal resistance factors. So attaining a speed in the 90s is a major achievment.

 

Indeed, and these would be the new clerestory corridor carriages of 1899-1900, which presented a rather larger surface area than the old arc-roof stock. So, credit to T.G. Clayton and his C&W DO staff, as much as to the Derby LDO staff!

[John-Miles]

According to Wikipedia, City of Truro was hauling 150 tons down a 1 in 90. Mallard was pulling a dynamometer car and 6 coaches - say 190 tons down a gradient of roughly 1 in 180 but it was a much bigger engine and streamlined. When you look at the comparison what the compound achieved is quite outstanding

Edited July 7, 2020 by John-Miles
spelling

[Compound2632]

2 hours ago, Edwardian said:

So, what you seems to be saying is that these small engines could go downhill at least as fast as large engines. That doesn't seem to make them any bigger, however.

 

You jest, of course, but the other table Nock includes at the end of his 19th century summary table is of fastest start-to-stop runs. The only Midland run featuring there is a budget newspaper special on 19 February 1848, from London via Rugby and the Midland to Scotland; a Jenny Lind 2-2-2 ran the special from Rugby to Altofts Junction, the point of hand-over to the York & North Midland, a little over 60 miles at an average of 56 mph - an extraordinary run for those early years. Most of the fast runs Nock lists are from the 1888 and 1895 races, in which the Midland was not a competitor. The West Coast and East Coast routes to Scotland largely avoid major population centres - perhaps Newcastle was the largest at the time - so high-speed non-stop runs of 100 miles or 150 miles were practical with there being few intermediate slacks (compare the slacks through Bristol for the Great Western Ocean Mails specials). The Midland route to Scotland took in many of the major towns of the east Midlands, important traffic centres in their own right. Also, the Midland was a difficult road, even compared with the Lancaster & Carlisle and Caledonian sections of the West Coast route - the fast runs down to Leicester or Nottingham that Ahrons and Rous-Marten record involved lengthy climbs at 1:176 and 1:200, as well as the opportunity to run downhill. By the 1890s, the Midland timetable required start-to-stop averages in the high 40s - low 50s; the best runs recorded are at averages in the high 50s.

 

As to size - which after all isn't everything, especially where high speed is concerned - of the engines listed in Nock's 80+ list, only the North Eastern Class M 4-4-0 and possibly the Caledonian Dunalastair I 4-4-0 could really be thought of as big engines by comparison with their Midland contemporaries. The 2631 Class Compounds were certainly very big for 1902, even if soon to be overtaken in size (but except in one case not efficiency or in any case speed) by the 4-6-0s of the new century.

 

Downhill: as @John-Miles has pointed out, the rolling resistance of the train certainly plays a significant part but the locomotive still has to be free-running itself. I don't think any British maximum speed record was attained on a gradient less steep than 1:200. In contrast, as far as I can discover the Wagner Baltic's sustained 200 km/h was achieved on a level line.

Edited July 7, 2020 by Compound2632

[John-Miles]

If you really want to get technical, the surface area of a small engine in relation to its power output will be proportionately larger than that of a large engine (surface area increases as a square of the lateral dimensions, volume as a cube) so the frictional resistance from the air will be greater for a small engine.

[PenrithBeacon]

1 minute ago, Compound2632 said:

..

As to size - which after all isn't everything, especially where high speed is concerned - of the engines listed in Nock's 80+ list, only the North Eastern Class M 4-4-0 and possibly the Caledonian Dunalastair I 4-4-0 could really be thought of as big engines by comparison with their Midland contemporaries. The 2631 Class Compounds were certainly very big for 1902, even if soon to be overtaken in size (but except in one case not efficiency or in any case speed) by the 4-6-0s of the new century. ...

And don't forget that the GWR produced its last Bulldog in 1911, a very small 4-4-0 (BR Class 2P) with double frames for goodness sake

[Compound2632]

4 minutes ago, John-Miles said:

If you really want to get technical, the surface area of a small engine in relation to its power output will be proportionately larger than that of a large engine (surface area increases as a square of the lateral dimensions, volume as a cube) so the frictional resistance from the air will be greater for a small engine.

 

But I think that the locomotive's surface area - at least that of the forward-facing surfaces - was a less significant factor than that of the carriages, in particular the effect of the turbulence caused by the gaps between them. I recall reading something on the wind tunnel tests done for both the LMS and LNER streamliners. I think the outcome was that streamlining only started to offer a significant reduction in air resistance above 90 mph. For the 1890s, I would suspect that bearing design and lubrication was the more significant factor, which is why I praised the Midland's C&W designers - with the clerestories they had evidently succeeded in producing carriages that, although taller, wider, and heavier, rolled at least as freely as the previous arc-roof carriages.

[Dave Hunt]

In 1931, the LMS commissioned the National Physical Laboratory to investigate the effects of air resistance and streamlining on locomotives with the LNER and Southern Railway contributing to the cost. The project was undertaken by the Aerodynamics Department of the NPL at their Teddington wind tunnel and was concerned with measures to overcome the problems of smoke clinging to the boiler barrels of big engines as well as reducing the drag of the locomotive and train. Air resistance tests involved models of LNER 'A3's and No. 10000 as well as three 'Royal Scots' - one without any streamlining, one with an ogival extension to the front of the smokebox, and one with a fully streamlined casing having a wedge shaped front. Results showed that the wedge shaped front and streamlined casing did produce definite reductions in air resistance above about 70 mph but the report warned that it would probably have to be part of a fully streamlined train for the benefits to be maintained. It added that the effects of side winds would also need to be taken into account. 

 

In 1936, tests were carried out in the LMS Research Department's new wind tunnel installed in the paint shop at Derby Works with partial streamlining of the three-car diesel-mechanical articulated set that was to enter regular service between St. Pancras and Nottingham early in 1938. There were features redolent of the German  Fleigende Hamburger as well as aspects of Wagner's work in the shapes tried and the eventual design had a rounded front with fairings under the buffer beams and between the bogies. A model of a streamlined steam locomotive with a shape sketched by the LMS Chief Locomotive Draughtsman, Tom Coleman, was completed with outside valve gear and a ‘peaked’ cab front and fitted with a polished wooden casing as well as valences to both engine and tender and rearward tender smoothing, the various streamlining components being removable so that alternative shapes could be tried. It was compared with the LNER's A4 style and what were described as 'some foreign designs', which were probably Wagner-inspired. Results showed little to choose between the various 'home grown' schemes and since the shape suggested by Coleman was easier to arrange on the engine, it was the obvious choice. Although its aerodynamic drag was higher than the NPL's suggested ideal, it was between 2% and 20% more efficient than that of the 'A4' depending on the cross-wind, the improvement increasing with the effective wind angle, and smoke clearance was at least as good. Based purely on the wind tunnel figures, the streamlined casing would reduce overall train resistance by up to 7% and at average running speeds could be expected to save between £220 and £300 worth of coal per engine per year. It was noted, however, that full streamlining of the train, with the gaps between the vehicles being shielded as well as the area below the platforms being enclosed in the streamlining, would be necessary for the full benefits to be realised.

 

And yes, the Johnson Compounds were BIG engines when they entered service.

 

Dave 

[Compound2632]

When I started at NPL in 1995 the wind tunnel building was still standing but was in use as the staff restaurant and demolished a few years later. I had some conversations with a colleague who had researched the history of the streamlining tests; unfortunately I lost any record of that when I left NPL five years ago but as I recall it was substantively the story given by @Dave Hunt, although I think there was some initial wind tunnel modelling done at Imperial College. There was also an LMS Journal article on the topic, I think, so I may be remembering from that too. The latter definitely said that the LMS poached a senior aerodynamic expert from NPL to set up the wind tunnel research group at the Derby Research Centre.

 

The ship tank building - used in the development of Barnes Wallis' bouncing bomb - was also still standing when I started but was also soon demolished. For most of my NPL career, I parked on the site. At that time, much of the NPL site was unchanged from what can be seen of it in the 1955 film but by 2000 it had changed beyond recognition.

[PenrithBeacon]

15 minutes ago, Dave Hunt said:

...

And yes, the Johnson Compounds were BIG engines when they entered service.

 

Dave 

And Fowler wanted to make a compound 4-6-0 too. Later he wanted to make a Pacific, but the outcome was the Scots, probably a better engine.

Regards

[Compound2632]

2 hours ago, John-Miles said:

According to Wikipedia, City of Truro was hauling 150 tons down a 1 in 90. Mallard was pulling a dynamometer car and 6 coaches - say 190 tons down a gradient of roughly 1 in 180 but it was a much bigger engine and streamlined. When you look at the comparison what the compound achieved is quite outstanding

 

To my mind, rather more impressive than City of Truro's high-speed descent of Wellington bank is Duke of Connaught's continuation of the run on to Paddington, averaging 80 mph over the 70 miles from Shrivenham to Westbourne Park. But that's getting rather far from Midland records.

 

27 minutes ago, Dave Hunt said:

In 1936, tests were carried out in the LMS Research Department's new wind tunnel installed in the paint shop at Derby Works with partial streamlining of the three-car diesel-mechanical articulated set that was to enter regular service between St. Pancras and Nottingham early in 1938. There were features redolent of the German  Fleigende Hamburger as well as aspects of Wagner's work in the shapes tried and the eventual design had a rounded front with fairings under the buffer beams and between the bogies.

 

There is rather a strong similarity in the style of streamlining carried by the Coronation pacifics and by Wagner's record-setting 05-002, apart from the baffles around the chimney on the latter, which I suspect were an afterthought arising from smoke still drifting into the drivers' lige of sight. Wagner's streamlining was also the result of wind tunnel tests - I believe the PTR (now PTB, the German equivalent of NPL, though far pleasanter) was involved.

[Compound2632]

Changing tack, I've plucked a sentence out of some private email correspondence. I'll leave it here as I think there is at least one reader who may be able to comment:

 

"It would be interesting to know whether the LB&SCR ever compared notes with the Midland about their respective electrification schemes."

[Edwardian]

29 minutes ago, Compound2632 said:

 

Wagner's streamlining was also the result of wind tunnel tests

 

I seem to recall that point being made before ...

 

[Regularity]

11 minutes ago, Edwardian said:

 

I seem to recall that point being made before ...

 

I think there are two points there, plus the horns of a dilemma...

[Dave Hunt]

1 hour ago, Compound2632 said:

There was also an LMS Journal article on the topic, I think, so I may be remembering from that too. The latter definitely said that the LMS poached a senior aerodynamic expert from NPL to set up the wind tunnel research group at the Derby Research Centre.

 

Indeed there was an article about the LMS Research Department in an LMSJ  - I wrote it. The chap from the NPL  that Harold Hartley persuaded to join the newly-formed research dept. was Johansson.

 

1 hour ago, PenrithBeacon said:

And Fowler wanted to make a compound 4-6-0 too. Later he wanted to make a Pacific, but the outcome was the Scots, probably a better engine.

Regards

 

The Midland's proposed 4 cylinder compound 4-6-0 was a Deeley scheme, not Fowler's, and a development of it was put forward by Derby LDO when the LMS were looking into replacing Fowler's compound Pacific with a 4-6-0 that eventually resulted in the Royal Scots. Had it been built it would probably have outshone the Scots.

 

Dave

[bbishop]

I'm very happy to be shot down in flames but actually how important was streamlining up to, say, 100mph?   This thread mentions it kicks in at 70mph, when does it become critical?

 

I would argue there are four other factors in achieving high speed:

the firebox - making enough steam

the boiler - storing it

the input system - getting the steam into the cylinders, including an efficient valve gear

the exhaust system - getting the steam up the chimney.

Have I missed any out, and how would you rate them?

 

Bill

 

 

[Regularity]

2 minutes ago, bbishop said:

I'm very happy to be shot down in flames but actually how important was streamlining up to, say, 100mph?   This thread mentions it kicks in at 70mph, when does it become critical?

 

I would argue there are four other factors in achieving high speed:

the firebox - making enough steam

the boiler - storing it

the input system - getting the steam into the cylinders, including an efficient valve gear

the exhaust system - getting the steam up the chimney.

Have I missed any out, and how would you rate them?

 

Bill

 

 

I vaguely recall Stanier saying that below 90mph it wasn’t really worth the extra cost.

Also that Gresley realised that reducing turbulence caused by the underframes and carriage ends was as important as streamlining the loco.

[Compound2632]

4 minutes ago, bbishop said:

I'm very happy to be shot down in flames but actually how important was streamlining up to, say, 100mph?   This thread mentions it kicks in at 70mph, when does it become critical?

 

I would argue there are four other factors in achieving high speed:

the firebox - making enough steam

the boiler - storing it

the input system - getting the steam into the cylinders, including an efficient valve gear

the exhaust system - getting the steam up the chimney.

Have I missed any out, and how would you rate them?

 

Bill

 

 

 

In the context of the Midland / LMS Compounds, a key change was made by Johnson for the second batch of engines, Nos. 2633-5, The first two engines, Nos. 2631 and 2632, had had independent control of the cut-off to the high and low pressure cylinders. Johnson had this changed so that the gear for the inside LP cylinder was controlled in tandem with that for the outside HP cylinders (it may still not have had exactly the same event timings?) This, as I read, had the effect of chocking the steam passages when the engine was being worked hard; the original pair could have the LP cylinder left with long cut-off, giving free steam admission. Nock states (op. cit.) that the highest speed he ever recorded with a Midand or LMS compound was 82 mph. He quotes a conversation with a Wakefield (ex-L&Y) driver, who said that he wished the Compounds had independent cut-off "like the French do - they could run much faster like that". Nock also observes that high downhill speeds weren't normally necessary with the Midland system of train loading, as the engines had enough power to work the trains uphill fairly briskly. This is borne out by Rous-Marten - in his account of 2632's 92 mph run he states that the 18 mile climb from Appleby to Aisgill was done in 23 min 5 sec - an average speed of just under 47 mph - and passed Aisgill summit at 43 mph. That load of 240 tons was on the heavy side for a Midland Scotch express between Carlisle and Hellifield.

[figworthy]

21 hours ago, Regularity said:

I think there are two points there, plus the horns of a dilemma...

 

That axe appears to have 4 points.

 

Adrian

[Compound2632]

22 minutes ago, figworthy said:

That axe appears to have 4 points.

 

Those were not the points he was looking at, I'm afraid.

[Buhar]

That was an interesting diversion in Early Risers, though it took some tracking back to follow it all.  I don't frequent that thread, so was a bit miffed to see serious railway discussion taking place.  

 

Dave, I don't think you can lay blame at Tuplin and Nock as being at fault for the continued view that the Midland had a "small engine policy".  I don't think David Jenkinson and Bob Essery would have been unafraid to re-appraise earlier thinking, but they reach the same conclusion despite both evidently having fondness and respect for the MR.  That said, I think they were thinking more of the effect of the Midland approach in the early days of the LMS.  There is no denying that the Compounds were good sized engines both when first built and when Deeley's full production started.  However, that was 1905 and 1907 and, apart from superheating them from 1909, that was it.  In terms of passenger locomotives the MR then continued it's programme of rebuilding the smaller 4-4-0s into the 483 Class 2P and reconfiguring 0-6-0s up and down power classes.  At the same time the fleet of 2-4-0s were still very active and over 250 came to the LMS.  The Midland just seems to have stopped locomotive development (beyond the drawing board) for itself after Deeley left.  The 4Fs were a 1911 design and didn't really meet the needs of a company with such substantial long-distance coal traffic.

 

Elsewhere similarly sized companies (and some smaller ones) were developing 2-6-0s, 4-6-0s and 0-8-0s.  Admittedly, there were not always a success, but they were addressing traffic needs.  Maybe it could be said that the Midland kept its traffic needs and locomotive design in balance (taking into account a desire to avoid expensive civil engineering works) and managed itself pretty well (apart from the London-bound coal traffic) but I think what irks and leads to folk like me teasing Stephen from time to time about MR motive power is the imposition of that thinking on the LMS.  The Compounds did consistently fine work on turns that matched their design brief, Euston to Wolverhampton for example, but were never going to be suitable as a WCML prime mover. The 4Fs, not withstanding Adrian Tester's attempt at rehabilitation, weren't big enough or sturdy enough to be the prime freight locomotive for the system as a whole and there were just too many 2Ps built.

 

On speed, I think there were quite a few free-steaming big-wheeled 4-4-0s dotted around that could probably get up to 85-90 mph in favourable conditions, the LY Flyers and the Dunalastairs leap to mind from other bits of the LMS.  That's not to decry the work of Midland engines in that regard; they ran freely, were very well looked after and I can't recall hearing of any Midland class having steaming problems at all, unlike a host of other designs.

 

Alan

[Compound2632]

5 minutes ago, Buhar said:

Elsewhere similarly sized companies (and some smaller ones) were developing 2-6-0s, 4-6-0s

 

We know who you mean - no need to be cagey! (Nice carriages there, BTW.)

 

10 minutes ago, Buhar said:

On speed, I think there were quite a few free-steaming big-wheeled 4-4-0s dotted around that could probably get up to 85-90 mph in favourable conditions, the LY Flyers and the Dunalastairs leap to mind from other bits of the LMS. 

 

A Dunalastair I is in Nock's 19th century top 13, at 85½ mph, whilst an Aspinall Highflyer and one of his 7'6" 4-4-0s were in Charles Rous-Marten's early 1900s 90 mph - 92 mph list.

[Regularity]

31 minutes ago, Compound2632 said:

 

Those were not the points he was looking at, I'm afraid.

You know me too well, Stephen!

[Dave Hunt]

Buhar, I agree that David Jenkinson and Bob Essery did at one time subscribe to the Midland's non-existent 'small engine' policy but I think that several people including myself and Adrian Tester managed to disabuse them of the notion. Since David was a friend and having co-written a great number of books and articles with Bob I am absolutely certain of it in fact.

 

The fact that Midland locomotive development effectively ceased after Deeley left was, as I have written many times before, due to factors such as hundreds of weak short-span girder bridges, relatively short lie-by sidings and others and the enormous cost of rectifying them rather than anything to do with a desire to limit locomotive size (and both Johnson and Deeley had wanted to build bigger engines). How much the Paget/Follows traffic control system developed around 1907 was responsible for encouraging the management to accept that there was no need for anything bigger than Compounds and Class 4 goods engines in the short to medium term I have never discovered but it would be surprising if it was not significant. The great insanity of 1914-18, of course, effectively put paid to the sort of expenditure the Midland would have needed to undertake to improve its infrastructure to accommodate big engines throughout the system so stagnation set in.      

 

As far as the 'imposition' of the Midland's thinking on the LMS is concerned, the composition of the higher management immediately after the grouping lends the lie to the idea of a Midland 'takeover' and forcing its ideas on the larger concern. There isn't the space in this forum (or I would imagine the interest to read reams of argument) adequately to address the issue except to state that it was economics that drove the LMS Board to adopt Midland designs in the short term whilst realising that altogether larger engines were needed for the future. It was largely due to the difficulties in satisfying the needs and desires of the disparate constituents, not to mention the unforgivable lack of co-operation between some elements within them, that delayed the introduction of what had been identified from the beginning of the amalgamation as the most urgent needs, namely an express passenger locomotive capable of satisfying the requirements of the WCML, a heavy freight engine, a large passenger tank engine, and a large mixed traffic locomotive. The gestation of the Horwich mogul, the 2-6-4 tank engine and the Royal Scot of course eventually met some or all of those needs but the heavy freight took longer to arrive. While the drawn out process of arranging for this to happen was going on something had to be done to address the traffic department's needs so the most cost-effective existing designs were chosen and these were Derby designs.

 

The above is a much simplified explanation of what happened. There is much, much more to the story and inevitably not everyone will agree with one person's analysis but there is a lot of myth, legend and ignorance of the facts peripheral to the decisions that were made that over the years have assumed the force of holy writ. And to suggest, as is often the case, that the men who were elected to the highest positions in the largest joint stock company in the world were somehow incompetent idiots who knew nothing about running a railway is ridiculous. Not, I hasten to add, that anyone who posts on this forum is so misguided.

 

I hope that the above is at least somewhat informative and maybe even interesting and that I am not opening a large can of worms in posting it.

 

Let's get on with some modelling shall we?

 

Dave