LNER Pacifics

[S.A.C Martin]

Evening (or morning!) chaps.

 

I spotted the magazine in the thread title in WH Smith this week, and bought it for my trip to Turkey later this month. Right up my alley I thought.

 

I perused it a little this evening, and came across the model section. All looked fine, until I glanced at the caption on page 110:

 

BELOW: Bachmann filled the last gap in the ranks of LNER 4-6-2 models with its Peppercorn A2, released in 2010.

 

I don't think I've ever felt so irritated by a caption description. It's by no means the "last gap" in Ready to Run Pacifics, if you want that of the LNER variety. There are four classes of Thompson Pacific as yet unavailable. Not one, not two - FOUR classes of LNER Pacific vintage not available ready to run.

 

However, I thought - perhaps it's a mistake, not indicative of a particular viewpoint. I started flicking back through the rest of the magazine - oh dear. Page 68:

 

Thompson: did his 'Pacifics' let the LNER down?

 

Reading the article - written by Howard Johnston - through to its end, I am staggered by the sheer amount of misinformation that has been put out in the article. The article states that all of the Thompson Pacifics were "bad riders and thoroughly unreliable". Neither of these two points have been related by either Messers Cecil J. Allen nor Peter Townend in their respective books to the extent that this article perpetrates them.

 

I'm also absolutely flabbergasted by the paragraph which reads:

 

They shook themselves to bits, with cylinders working loose, bolts shearing, pipes splitting and frames developing fatigue. They were also heavy on coal.

 

None of which paints a picture which is specific to any of the four classes, A1/1, A2/1, A2/2 or A2/3.

 

Certainly things like frame cracking happened, but the picture painted in this part of the magazine, and earlier from page 17 onwards of Thompson's machines reads less like an informed viewpoint, backed up with the necessary statistics (I note the average coal consumption figures for said classes were not related in the articles - for the record, Cecil J. Allen's British Pacific Locomotives has an excellent set of average figures for all the Pacific classes of the LNER).

 

There is no mention of the superiority of the A2/3 over its Thompson peers, or any of the comparison trials which showed up some interesting facts on the full coal consumption per mile averages for the classes (which was found, incidentally, to be dependent on how the locomotives were utilized, and on what routes and types of train).

 

Reading the rest of the magazine is a trite disappointing too. There are some terrific photographs from all quarters, but the whole magazine is very disjointed, and the order of its articles not very well thought through.

 

I can understand that we will all have differing opinions on the merit of any C.M.E.'s locomotive designs, but for publication, claims that the locomotives in question "shook themselves to bits" should be backed up with some form of reference material proving this to be so.

 

Overall, the magazine really just felt like an excuse to single out Edward Thompson for criticism, and to be frank, if you've an interest in LNER steam, this magazine is probably best left on the shelf as it does not relate anything new, but perpetuates a line of thinking which should have died out a while ago, with the wealth of knowledge and statistics on the locomotives out there, not to mention the excellent first hand accounts from people like the aforementioned Peter Townend and Cecil J. Allen.

 

A great pity as the overall design, presentation and the printing of the magazine are all excellent.

[Bernard Lamb]

A good review.

I picked it up in 'Smiffs' and after glancing at about three pages put it down again. Just one of those comments was enough for me. It was the reference to models that I noticed. A pity as there are some good parts. An opportunity missed. Sadly people will buy it and these stories will gain a wider audience.

Bernard

[micklner]

Somewhat overpriced as well . Most of the pictures are well known too.

Again a Smiffs viewing/price was enough for me.

 

As to the usual Thompson bashing its the usual load of shoemenders. The A2/3 were fine looking engines and reached high mileages and much better than the earlier Thompson Pacifics which were compromised by using the P2 and V2 as bases .

[Guest Max Stafford]

Yep, following the Barbara Castle 'airbrush job' in the Beeching volume, we now have the Thompson 'hatchet job' in this one.

 

Why people continue to spout this drivel is beyond me, it's no secret that the A2/3s were actually very good engines, as was Great Northern. You can't write the B1 off as a failure either, let's be honest.

Thompson also pulled off some half decent rebuilds of 2-8-0 types and although Arthur Peppercorn gets the credit for the K1s, these were largely Thompson inspired.

 

I haven't seen this publication myself but I'm sure there will be the inevitable comments about awkwardly placed cylinders on the pacific classes and yet strangely, this is never heard in relation to Kings and Princess Royals - why's that then?

 

Anybody wanting a balanced and objective assessment of Thompson's work needs to look no further than the Oakwood Press book.

 

Dave.

[davidw]

Saw the publication great photos' left it on the shelf

[coachmann]

Yes it is irritating to see scribblers still pandering to old trackside-commandants predudices. Whether Howard Johnson should know better I don't know. He was a cribe at EMAP for 'Rail' and might be more at home with diesels. Steam Railway, Smiths and serious railway stuff shouldn't be in the same sentence.

[34theletterbetweenB&D]

The comments on the Thompson pacifics seem pretty well justified. Dig out what was reported by the RCTS at the time they were in operation, and the memoirs of those who had to operate and maintain them, and a clear enough picture emerges. As power units they were fully up to standard, a Doncaster round top wide firebox boiler with a double Kylchap ejector, combined with a steam circuit arranged with the knowledge gained in the Gresley developments, placed them in the first rank of UK steam locos for efficient power production. But the riding quality and increased maintenance burden deriving from Thompson's principle of placing the cylinders for equidistant length of connecting rods proved their Achilles heel.

 

The operating department pretty quickly relegated these locos to duties well below their maximum power capability, because the crews frequently had an uncomfortable job if express speed was required, and the maintenance burden rose significantly due to the forward frame flexing when their full power capacity was regularly exploited. The reversion to something more like the previous Doncaster pacific layout by abandonment of the equal length of connecting rod requirement once Thompson had retired would not have been undertaken on a whim: and note that pretty much the same components on the resulting slightly shorter frame produced locos that were both operationally successful and economical to maintain.

 

That is proof enough that Thompson was mistaken in specifying this requirement for his pacific designs, as when eliminated successful locos resulted. That would have been true even if the Thompson pacifics had been operationally similarly successful. And as the record shows, they were not.

[The Stationmaster]

Having written in the past about some of the problems with a number of Thompson designs and before doing so having spoken to those who both drove and maintained them I tend to agree with the generality of the comments above. Some of the Thompson pacific front ends were well known for 'working' or flexing and it was far from unknown for that to result in bolts and rivets being loosened or even falling out as well as other problems. And for some reason a number of Thompson designs, including some of the pacifics, were grossly disliked for becoming very rough when they were on high mileages - not just in respect of the pacifics but many footplatemen who had experienced the difference much preferred B16s or B12s to B1s. Some of the latter might well have been down to the design of the B1 bogie - which has also been suggested as a likely cause of rough riding on the pacifics which also used it.

[Guest Max Stafford]

The rough riding issue wasn't just confined to Thompson's designs it has to be said; Peppercorn's otherwise first-rate A1s suffered badly from this phenomenon as overhaul time approached. Whilst it's generally accepted that the equal length con rods were an evolutionary dead end which prevented optimum performance, the pure-bred Thompson A2/3s proved to be pretty steady locos even if that big end gave more bother than more conventional arrangements.

 

Some cite unreliability as the reason for the early withdrawal of both the A2/2 and A2/1 designs. This isn't true, it was purely and simply down to the fact that these were numerically small classes and therefore for logistical reasons likely to be the first in line for redundancy when the new EE Type 4 diesels arrived in strength.

 

Some of the perceived reputation of these machines was based on anecdotal evidence from crews at specific depots (and I include the B1s in this) and this should be borne in mind when making an objective summary. One only has to recall the generally cool and often hostile reception the Britannias got on the Western to understand how entrenched attitudes could be in the face of the unconventional.

 

Dave.

[The Stationmaster]

The rough riding issue wasn't just confined to Thompson's designs it has to be said; Peppercorn's otherwise first-rate A1s suffered badly from this phenomenon as overhaul time approached. Whilst it's generally accepted that the equal length con rods were an evolutionary dead end which prevented optimum performance, the pure-bred Thompson A2/3s proved to be pretty steady locos even if that big end gave more bother than more conventional arrangements.

 

Some cite unreliability as the reason for the early withdrawal of both the A2/2 and A2/1 designs. This isn't true, it was purely and simply down to the fact that these were numerically small classes and therefore for logistical reasons likely to be the first in line for redundancy when the new EE Type 4 diesels arrived in strength.

 

Some of the perceived reputation of these machines was based on anecdotal evidence from crews at specific depots (and I include the B1s in this) and this should be borne in mind when making an objective summary. One only has to recall the generally cool and often hostile reception the Britannias got on the Western to understand how entrenched attitudes could be in the face of the unconventional.

 

Dave.

 

I think the 'Brits' on the Western were a rather different issue Dave as in effect requiring a Driver to re-learn the road from Plymouth to Paddington while his Fireman tried to learn to fire left-handed was a bit of an imposition on a loco which otherwise had only a couple of bad points for almost all but a certain Laira Driver and a couple of Motive Power Superintendents (who skillfully off-loaded the locos onto a colleague's patch when he volunteered to take them).

As far as Thompson's work was concerned my view is that comments from fitters and foremen who had to deal, or try to deal, with problems, such as rivets shaking out, at running shed level cannot be ignored - and they weren't necessarily Gresley afficionados but included men who came to the job post-war. Incidentally I think that the Peppercorn A1s also had the B1bogie? A pal of mine undoubtedly has a jaundiced view of Bis as he was thrown off the footplate of one due to the loco's rough riding (fortunately he managed to grab a handrail as he went overboard and managed to climb back) but everyone I've known who worked on them had a very poor opinion of the riding of the class once they had mileage on or were approaching shopping. Obviously much of what we have learnt about locos in everyday working has been what has been handed down and it was always my experience at loco depots that some of the first Drivers one got to know by name were the moaners - maybe the same applies to some handed down stories about locos?

[S.A.C Martin]

I don't know what the grounds are for being a "successful class" but they can't have been so un-drivable that they didn't then work out twenty years service for the Eastern Region?

 

I do think there's a certain amount of picking and choosing the facts to relate. Everyone has mentioned the frames cracking: I was always led to believe this was a problem only certain variants of the LNER Pacifics had. Yet I find reading the RTCS volumes, and several dozen other titles on the LNER Pacifics, that they all suffered from it. Some more than others, granted, but given the larger classes had spare frames for overhaul in any event, why is this picked out as a particular fault of the Thompson Pacifics, when all the Pacific classes suffered from it?

 

Dave makes a very good point about the small numbers in each class. I'd also challenge to some extent the expectations of these locomotive classes - all developed and built during wartime (sans the class A2/3, reputedly the best of them), all used as many standard components as possible (short length connecting rods being one of them), and in the case of the A2/1s, they were in some respects a Pacific variant of a highly successful 6MT class. What exactly was expected of the Thompson Pacifics, when built?

 

Given all of the Pacific classes Thompson built incorporated features such as, in the firebox, a rocking grate and hopper ashpan (which greatly simplified the process of dropping the fire and emptying the ash from the grate), axle-driven alternators and electric lighting, amongst other changes (removing the Gresley conjugated valve gear WAS a good thing, and this was perpetuated on the later Peppercorn designs, albeit by changing the position of the centre cylinder again) can they really have been such bad locomotives to merit the amount of disdain they seem to have acquired?

[coachmann]

Talking to a Gresley fan about Thompson is a waste of time..... All locos got rough as they approached their shopping date so maybe the Thompsons got rougher quicker. I've never ridden on the footplate of a fast loco but I can imagine it was quite alarming when one went into a swing. My experience of rough locos was with Austerity 2-8-0's and they started to gadabout at 20mph! Knowing the working mans mentality for "easy", if the Gresley A3's and A4's were comfortable at speed then they would naturally critisise any loco that wasn't .

 

I experienced a similar predudice when I left the railway to work on Oldham buses. Drivers hated the Daimlers because there were only around 25 of them in a fleet of around 200 Leylands and a some Crossleys. The gear change was different and drivers were afraid of the pre-selector pedal in case it wasnt dipped fully and came up through the cab floor to trap their shin. Therefore "Leylands were good.....Daimlers were bad 'uns"....

[34theletterbetweenB&D]

The comparison with the Gresley pacifics and V2s was undoubtedly a killer. Although these could get rough when run down, in normal trim they were in the top bracket for footplate ride. The Peppercorn A1s (not the A2s for some reason) were also adversely compared to the Gresley pacifics, with a tendency to develop a pretty large amplitude yawing motion, and eventually this was traced to insufficient bogie side control spring force; Peter Townend writes this up briefly in his 'Top Shed'. When the side control spring loading was near doubled from the original design value (empirical experimentation) the riding came good by all accounts. But none of this detracted significantly from the Peppercorn A1 as a traction unit, the crews were happy with them as they would pull the side out of a house and were otherwise very little trouble.

 

The mention of Britannias is interesting. These were adversely commented on by any number of observers for a harsh crew ride, and had numerous troubles in their early existence, far more than Thompson's pacifics. Slipping wheels on axle seats, and bits flying off in all directions as the cylinders ruptured, random breakages including a tender drawbar failing (imagine what current H&S reaction would have been to that) yet of course they were made to work : the chief engineer was there to direct matters, and the entire weight of the BR hierarchy whose 'brave new railway world' could not possibly have produced something inferior to previous designs insistent on success... At least some of the Thompson pacific failings would probably have been overcome if a man with a stake in their success had been able to supervise. But of course he had left office just as peacetime made it possible to assess design weaknesses and get on with correcting them. So they were pushed aside as 'somebody else' problem.

[S.A.C Martin]

Just regarding the A2/2s...there's no doubting the performance of Gresley's P2s in terms of work, tractive effort and timekeeping. But 75-90lb a mile coal consumption compared to 45lb a mile, when rebuilt as A2/2s, in wartime?

 

Whilst I do think the beauty of the P2s was immense, and that with hindsight, their use on other mainlines might have proved their worth further, simply on the basis of economics, nearly double the coal consumption of their rebuilt forms is astounding. I was not aware it was so acute until glancing through Peter Graffon's book this evening.

[34theletterbetweenB&D]

But how do you know what those P2 coal consumption figures relate to in power output and driving technique? That 50 sq ft grate was quite capable of burning a lot of coal if put to it, and a sustained output of 2,000 drawbar horsepower eminently possible. To produce that output requires of the order of 6,000lbs of coal per hour firing rate: at 60-70mph, the typical average for express steam speed, the coal would be going on the grate at 100lbs a mile. If the fireman was up to it, the power could be had: 'next door' when the Duchess was fully extended on trial two firemen were required to get the coal in fast enough, and they still couldn't keep up, briefly peaking at about 8,000lbs per hour. Driving technique is another significant factor, Dick Hardy gives a splendid account of an LMS conductor driver applying the usual technique for a Midland engine to an A4, large cut off and barely opened regulator, and sending most of the fire up the chimney for very sluggish forward progress. A little driver mismanagement and coal consumption rockets.

 

When the P2 prototype was tested in France it turned in a performance of 3.25 lbs of coal per drawbar horsepower hour. That's 'right in the ballpark' for a large simple loco of Doncaster wide firebox design. The same design of boiler and steam circuit doesn't magically become more efficient by removing a pair of driving wheels. That's an axe you can hear being ground...

 

 

[micklner]

When the P2 prototype was tested in France it turned in a performance of 3.25 lbs of coal per drawbar horsepower hour. That's 'right in the ballpark' for a large simple loco of Doncaster wide firebox design. The same design of boiler and steam circuit doesn't magically become more efficient by removing a pair of driving wheels. That's an axe you can hear being ground...

 

 

 

I quite agree on your arguement re consumption figures etc. The figures are from the 1930/1940s how accurate in those pre computer days are any of the quoted figures? All figures can be altered to suit any survey and is still done today just look at "average" mpg quoted for many cars , how many would ever achieve those figures in real life.

 

Cock O The North was on a rolling road without the effects of wind, quality of track , no natural loading of any kind and probably using the best qualiity of Coal etc etc. So hardly normal figures. The P2 were never used to their full potential if Gresley had admitted they werent suitable for Scotlands curves and ran them from Kings Cross ,how the story may have been so different.

 

The comments made by Peter Townsend in his superb book on LNER Pacifics are words from someone who had day to day experience with all the LNER Pacifics and he praises virtually all of Gresley Thompson and Peppercorns for the superb Locos they were .

 

So very sad that more never survived for future generations.

[coachmann]

Try telling this young lad in the 1950s that his fav engines were amongst the worst designs ever built by the LMS. I have always been an enthusiast and not a trackside engineer/superintendant, so all I saw was sheer magnificence and raw power. Same with Thompson Pacifics. Bring on the models....

 

 

 

 

[S.A.C Martin]

Right, so if we ignore all the statistics quoted by Cecil j Allen, dw winkworth, that leaves us simply with anecdotal evidence that the Thompson A2s were heavy on coal (which is related in the concerned magazine without figures to back it up).

 

Surely one or the other is true of all the locomotives concerned? Fuel consumption is based on the crew and the road taken.

[The Stationmaster]

Right, so if we ignore all the statistics quoted by Cecil j Allen, dw winkworth, that leaves us simply with anecdotal evidence that the Thompson A2s were heavy on coal (which is related in the concerned magazine without figures to back it up).

 

Surely one or the other is true of all the locomotives concerned? Fuel consumption is based on the crew and the road taken.

 

Yes, and a lot of 'no's. Coal consumption on otherwise identical locos in the same mechanical and thermal condition hauling exactly the same train with the same load and rolling resistance and in similar weather conditions then the crew and the nature of the road do play a part although most crews were of a reasonably similar standard and the ones that would stand out would be the heavy handed Drivers, poor Firemen, excellent Drivers with a light touch and the really skilled Firemen. In other words very much of a a broadly similar performance for the majority of men but the good 'uns and truly bad would stand out - albeit for differing reasons.

 

But to that you can add, albeit mainly in later years, vagaries in loco condition and performance due to poor maintenance of lack of servicing staff or the efforts of good sheds compared with bad, vagaries in the weather, vagaries - albeit usually minor and of very limited effect - in rolling stock, variation in the quality of the coal and so on. The only truly comparable figures come from stationary test plants where mainly of the vagaries are either eliminated or carefully controlled or from carefully controlled road testing which mitigates some of the vagaries and takes note of the others. But finally good enginemen would always know a bad loco or class of locos from the sheer amount of shovelling if little else, and if a particular class persisted in delivering nowt but hard work its reputation could well be sealed.

[Guest Max Stafford]

I suppose it should also be considered that due to the nature of the engineering and individual fettling required in works, each engine was virtually bespoke. Automated production line technology and computer engineered tolerances as we recognise them today simply didn't exist and this probably meant subtle, if minuscule differences between individual machines that could nevertheless have an effect on the performance of that machine.

If you understand what I'm getting at...!

 

Dave.