Why did the 20s outlast other classes?

[The Stationmaster]

Plain simple English Electric reliability, plus, as a pair, lots of tractive effort? They will also have benefitted from being lower geared than many of the comparable Type 2s.

 

Jim

 

Plus the pairs in which they worked gave extra Brake Force and braking weight - very handy when working freights.

[Phil Bullock]

And 8 traction motors rather than the 6 of a type 4....

 

Phil

[jim.snowdon]

As others have said, simple, light weight locos used in pairs on MGRs 2000hp spread over a pair with 8 traction motors able to put down power on dodgy track. A low speed Lugger, just what railfreight wanted. 25s ? Too many differences between a nominally single class, they were /0 /1/2 for a reason, not all worked together well. All 20s were the same, to use an Americanism KISS, Keep It Simple Stu*id ! BR clas 56, 58, 60 all got more and more complicated to be replaced by the simple 66.

It's not so much the power that matters, but the ability to put down 84,000lb of tractive effort on the rail and get the train on the move - horsepower is more relevant to how fast it can then move the train.

 

Jim

[coachmann]

Not a particularly exciting class, but they lasted long enough to become interesting.  20 044 and 20 134 reversing a train of empties into the yard at Chinley on 5th August 1977 prior to returning light to Toton....

[PatB]

Lima or Bachmann?

 

 

 

One of those photographs that looks like it's of a model railway.

 

 

 

 

 

Jason

Wrenn. If you look really hard you can see the body retaining screw in the roof .

[Dava]

A thing to look for is how long it took for a loco to go from green to blue. This was done at main works overhaul, and the longer between works visits, the cheaper and more reliable a loco is. The class with the last locos in green are the 40s, 20s, and the 08s. 

 

PS-The 47s dont count as they had major engine troubles requiring replacement. This was done early in their lives so reset the time between works visits.

Some 20s were so sun-bleached it was hard to tell. D8154/20154 on the GCRN had such a faded blue before withdrawal a year or so ago, still in BR livery, it was difficult to make out the blue was not green.

 

Dava

[The Johnster]

60mph in the 70s when I was a guard at Canton; I worked a class 8 train from there to Cardiff Tidal with a pair and a Gloucester driver once, and secondmanned him to Canton.  He claimed they were a bit rough at speed singly, especially light engine, and believed the weight was poorly distributed between the bogies, but better in pairs.  I doubt a single loco had the power to take any train much over 60mph anyway; don't forget 60 was still thought of as a fairly respectable speed when they were introduced, and more than adequate for their intended pick up and transfer freight/ecs work.

[Jim76]

Not a particularly exciting class, but they lasted long enough to become interesting. 20 044 and 20 134 reversing a train of empties into the yard at Chinley on 5th August 1977 prior to returning light to Toton....

WEB Class 20's Chinley 1.jpg

Hi Coachman, what working would've this been? Jim

[coachmann]

Hi Coachman, what working would've this been? Jim

I didn't ask. I was chatting in the signalbox when I was told these 20's were on their way off the Hope Valley line. Trains for Peak Forest had to reverse in Chinley Station yard in those days. I was invited aboard........It would have been rude to decline, although cabbing a diesel wasn't really my thing.

[25901]

Didn't the 25s develop body and cab rust issues later in life? 

 

Boy do I know that fact but that's another story. Having been on both in BR service, working on both in pres. and co-owning both too in pres. 20's always seemed hold themselves well but the 25's had a bit too much bounce at speed, remember been thrown out of the secondman's seat in a 25 going over a bad track joint at over 50 mph that didn't effect us in a pair of 20's a few weeks later.

[Jeff Smith]

I am not a D/E enthusiast nor do I know much about U.S. motive power despite living here, but mention of the 20s being out of date partly because of having only one cab makes me wonder why U.S. freight locos that I see in action are all single cab albeit with better visibility than a 20?

[cheesysmith]

In the USA they did/do accept poorer visibility from the cab. Norfolk Southern (NS) even specified their diesels to run with the long end forward, so you had to look along the entire length of the engine to see where you were going, on the theory that if you had a accident there was the full length of the loco and engine bay between you and whatever you hit. But it comes down to the trains in the USA being run with multiple locos, and if you have more than one on the front you can make sure you have a cab facing the right way, so why pay for more than one cab?

[SRman]

One other contributor to class 20 reliability that hasn't been mentioned was the lack of train heating. In many of the diesels earlier days unreliable steam heating boilers featured prominently in locomotive availability figures. Class 20s had no such problems because they didn't have steam heating boilers.

Of course, in later years when steam heating was superseded, many of the surviving types became more reliable (or more available, if you prefer), while earlier unreliable types had been withdrawn and scrapped - some such as the baby Deltics and Co-Bos were unreliable from the getgo, regardless of steam heating!

[Zomboid]

Deleted - Wasn't adding anything

Edited December 26, 2017 by Zomboid

[Clearwater]

A related question would be why so many other classes were commissioned once it was clear that a good, robust design had already been produced?

[Rugd1022]

A related question would be why so many other classes were commissioned once it was clear that a good, robust design had already been produced?

 

A lack of joined up thinking and an element of separation in the ranks between the regions I'd say, the WR were allowed to plough their own furrow with the Hydraulics despite reservations amongst the top brass, which probably wouldn't be allowed to happen today. The initial plan was to build a certain amount of pilot scheme locos and revue their suitability and reliability before placing larger orders, but this soon fell by the wayside when the order came from above to rid all six regions of steam as soon as possible. A combination of Modernisation Plan, the Beeching Report and the National Traction Plan overtaking each other in a relatively short space of time and changing commercial patterns meant that by the late '60s BR had too many different types of loco on its hands and wanted rid of the less reliable ones. Only a few years later in the early '70s the WR found itself with a chronic shortage of motive power which is why some of the Warships were given a reprieve in 1970. No Hydraulics were withdrawn that year but at the end of 1971 there was massive cull, yet they were still short of power for a year or two afterwards!

 

EE weren't without their problems but overall gave better service than the Sulzers and Maybachs in that short but fascinating period change on BR.

Edited December 26, 2017 by Rugd1022

[Foden]

Very true, but I suspect it was because that solid design could have, and probably should have been improved on with the other classes, but poor design and poor components negated that.

[Legend]

A related question would be why so many other classes were commissioned once it was clear that a good, robust design had already been produced?

I think it’s the need for constant development and always find something better. The Clayton was perceived to be that better loco mainly because of its central cab that gave improved visibility. And it probably would have been the new standard the 1 .....had it worked! Of course they were chronically unreliable and more Class 20s had to be built to replace them .

[Andy W]

There was a very senior BR engineering manager called Freddie Harrison who had an unreasonable dislike of English Electric diesel products, and did his very best to prevent orders going to them.

He's certainly to blame for the vast numbers of class 47s with their too-highly-stressed Sulzer engines, instead of at least a proportion of DP2s. You can see the battles he lost when non-EE products failed to live up to expectations - additional Class 20 orders when the Claytons were such a disaster; the Class 50s, when the 47s had to be de-rated; and the re-engining of class 30 to class 31 with EE engines,

[Clearwater]

Thanks - I’d forgotten the extent to which individual agendas prejudiced otherwise logical purchasing decisions...

[cheesysmith]

Try reading this page, especially the bit about the engines for the claytons.

 

http://www.paxmanhistory.org.uk/paxrailt.htm#ic125

[cheesysmith]

There was a very senior BR engineering manager called Freddie Harrison who had an unreasonable dislike of English Electric diesel products, and did his very best to prevent orders going to them.

He's certainly to blame for the vast numbers of class 47s with their too-highly-stressed Sulzer engines, instead of at least a proportion of DP2s. You can see the battles he lost when non-EE products failed to live up to expectations - additional Class 20 orders when the Claytons were such a disaster; the Class 50s, when the 47s had to be de-rated; and the re-engining of class 30 to class 31 with EE engines,

 

You have to remember that he sold the idea on the fact that engine overhauls at works was the same cost per cylinder so the Sulzer engines with only 12 cylinders were cheaper to overhaul. brush in the tender for the class 47 actually put forward a design using the 16 cylinder EE engine that would have been cheaper and lighter than the Sulzer version.

 

Sulzer were very conservative with the loadings/RPM of main bearings, so limited their engines until too late for BR requirements. They were still using 2 valves per cylinder, and did build a experiment 4 valve per cylinder engine with higher RPM but was overtaken by the need to solve the problems of the class 47s. If the R series engine had worked, you cold have had a straight 8 in a 33 with 2400BHP. 

[The Johnster]

Boy do I know that fact but that's another story. Having been on both in BR service, working on both in pres. and co-owning both too in pres. 20's always seemed hold themselves well but the 25's had a bit too much bounce at speed, remember been thrown out of the secondman's seat in a 25 going over a bad track joint at over 50 mph that didn't effect us in a pair of 20's a few weeks later.

 

Seconded with bells on!  Our Hymeks at Canton in the 70s were replaced by 25s, a very poor deal in my view.  The 00.25 Cardiff-Peterborough express parcels, which we worked to Gloucester and back with the same engine on the Peterborough-Cardiff balancing working, was an easily achieved 90mph delight with a Hymek, but a draughty, noisy, spine jarring, tiring nightmare with a 25 that struggled to reach the speed. and was diabolical once you got to 60 or above.  I wouldn't have called it bounce, as this implies that the springs didn't bottom out, which they bloody well did!  Few drivers were willing to push them to the limit; it felt and probably was dangerous...

[russ p]

I've ridden on some bloody rough 20s in my time some in the last few years

[The Johnster]

I've ridden on some bloody rough 20s in my time some in the last few years

 

Can't comment on 20s, the only ride I ever had was the one above from Cardiff Tidal to Canton, which was fine, but 25s were, in my limited experience, the worst riding main line loco I ever rode on (though I've heard hair-curling stories about rebuilt Royal Scots).  Only 08s were worse, and not by much!