A thought I have over classification systems (of all sorts) is that someone comes up with a nice logical system - but once exposed to reality there are things that don't quite fit, leading to anomalies, and then people forget or never understood the underlying logic, leading to more of them... so the best thing is to accept things as they are, without worrying...
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Question About TOPS Subclass Numbering
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This is the right answer.
The Chief Mechanical and Electrical Engineers (CMEE) Department and the Operations Department had different subclass lists that they used internally. This was only exposed when the decision was made to comprehensively renumber the loco fleet. The revised subclass list used from early in 1974 was a compromise negotiated between the two departments. The result is pragmatic not logical.
IMHO - idea only - no fact - is 41 - if anything - was more likely to have been D800-802 - those three were different in many ways to D803 onwards.Regarding the question of 'class 41'; I have in front of me the Railway Observer (quoted in my earlier post) listing the then new codes. As D7666 states, it's not on the list.
The observation I'll make is that there are several gaps in the numbers, but I can see some logic for it;
Class 31 is 1470 hp, 32 is vacant then 33 is 1550 hp. 34 is missing, then 35 is 1700 hp.
Similarly, class 40 is 2000 hp then 42 is 200/2200/2400.
I think a gap is just to separate power; if 41 is.a gap because the D600s were intended, there should also be candidates for cl 32 and 34. if anyone can come up with type 3 classes withdrawn just before the scheme was introduced, I'd be interested to hear what they were
If, in an early draft, 41 had been allocated and then the class withdrawn I would suggest that the other numbers would be moved up to close the gap.
On the subject of coupling codes I remember at the time on a Freedom of Scotland bash that the NB type 2a - D6100 - had varying coupling codes - oranger star and white diamond from memory (sorry if that's wrong, it was 60 years ago). I mean the ones before rebuilding.
Merle Haggard
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The class divisions do have an h.p. factor, and making the 2000 h.p. Warships class 41 would be logical - but that would also include D803-29. Class 42 is unique in containing three different h.p. ratings In other cases basically similar locos had different classes based on h.p. e.g. 24 (1160), 25 (1250) and 44 (2300) and 45 (2500). The fact that the list in the R.O. (presumably a BR list verbatim) has columns Class, Type, H.P. and Numbers suggests that H.P. was an important factor in the scheme.
But that is just an idea, like yours.
D801 was withdrawn in 08/68, D800 and D802 in 10/68 and D830 in 03/69. All were reported in Railway Observer two months later, and all were shown as class 42.
Well you see, even that varies from what sources you look at.
D800s. hp @ rpm
Maybach MD650 | D800 type | 1200 @ 1500 | 1150 @ 1500 | 1135 @ 1530
MAN L12V18\21B | D833 type | 1100 @ 1500 | 1056 @ 1500 | 1100@ 1530
Paxman 12YJX | D830 type | 1250 @ 1500 | 1200 @ 1500 | 1135 @ 1530
UIC rating [metric bhp] and speed [rpm]
British Standard rating [British bhp] and speed [rpm]
WR setting [British bhp] and speed [rpm]
So you see, as Swindon set up engines, there were only 2 horsepowers, and all the rpms 1530 not 1500, and not much of that actual data agrees with IA ABC Books Of Numbers.
There is SO much minutiae in all this that just does not fit either exact BR classification or OCD compartmentalisation.
None of this is new. Kettles could be worse. Far worse. e.g. LMSR Jubilees. 191 locos. Most spotting books will only tell of one type. There were actually 5 basic types AS BUILT with different wheelbases, different boilers, different grates, five different weights, and that is before looking at tenders. Over time there were 5 different boiler types in 8 different heating surface versions, different tubes, different flues. Net result there were 19 different diagrams issued for them again before looking at tenders.
Black 5s : 9 different boilers, and 11 versions when you just look at valve gear and with/without roller bearings and bearing type.
What it comes down to is no numbering or classification system can handle all this in a practical way - and it is all far far more complex than trainspotting conventions believes. This is why companies have asset databases, be it paper records of the past or computer files these days.
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Merle Haggard
Established Member
The 'The Book of the Warships' (Orwell Press ISBN 978-1-906919-11-5) has a lot of detail - including pages of lists of experiments and mods. Worth getting if you're interested, and I mention it because 'The Book of the xxxx' series is about steam loco classes apart from this one so might have gone under the radar. Too late at night for me to study to see what it says about power ratings, but likely to be in there somewhere. Getting off-topic I know, but interestingly details the cause of rough riding - the German designers had made a miscalculation in the geometry of the arrangement forming the virtual bogie pivot (they couldn't have a real one because of the mechanical drive).
I have it.
That is not where the tekkie gen comes from but from a much earlier work.
I also have the equivalent (and deeper) German language books on V200s (and V160s) (on which Warships (and Hymeks) were based) and also on the V80s which preceded the V200s and where much of the development was done.
Fairly well read around the subject TBH.
Clarence Yard
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As I stated on another thread, I used to work for the man, who as a very senior clerk in the CM&EE BRB pre 1969, was involved in the drawing up of the class numbers.
He told me it was done in hp order but, on request, the small sulzers were grouped by builder, not in strict hp order. Grouping by overall type seemed to be a preference. Individual locos with a different hp to the rest of the main class were ignored, for reasons of simplicity. Initially, there were no sub classes.
Everything that existed in 1965/6 would have been allocated a class number. Shunters of different builds were grouped, such as in class 05. He did say they were gaps in the DML numbers for possible future builds.
Unfortunately the surviving CM&EE papers of the period don’t seem to deal with this matter so I suspect we will now never know the evolution of the list preceding the list which appeared in that RO. We can guess but we could be very wrong!
He told me it was done in hp order but, on request, the small sulzers were grouped by builder, not in strict hp order. Grouping by overall type seemed to be a preference. Individual locos with a different hp to the rest of the main class were ignored, for reasons of simplicity. Initially, there were no sub classes.
Everything that existed in 1965/6 would have been allocated a class number. Shunters of different builds were grouped, such as in class 05. He did say they were gaps in the DML numbers for possible future builds.
Unfortunately the surviving CM&EE papers of the period don’t seem to deal with this matter so I suspect we will now never know the evolution of the list preceding the list which appeared in that RO. We can guess but we could be very wrong!
This is a long shot but I'll ask anyway. The 9Fs and other late steam locomotives were withdrawn long before they were life-expired, and I personally believe that had the 9Fs in particular not been withdrawn they could in theory have been used until the late 90s. Obviously that is based only on age and not based in reality, but it's made me wonder what would have happened if steam locomotives lasted a few years longer. Are you aware of whether there was any thought put into steam locomotive classifications beyond the generic Class 98 numbering in the event the planned withdrawal of them was delayed enough that steam locos would need to be given proper TOPS numbers?
norbitonflyer
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Intriguing - so as well as 10001 (withdrawn 1966) this brings several shunter classes into scope (Data from "Diesel & Electric register, by Andy Chard: corrections welcome): unless stated all tghesed classes went extinct in 1967
D2400 etc - Class D2/5 Barclay 0-6-0 (same 204hp Gardner engine as classes 03-06: note that the Barclay Class 06 was an 0-4-0) extinct 1969
D2500 etc - Class D2/7 Hudswell Clarke 0-6-0 (same engine as classes 03-06) - end cab
D2510 etc - Class D2/12 Hudswell Clarke 0-6-0 (same engine as classes 03-06) - centre cab
D2700 etc - Class D2/1 North British 0-4-0 diesel hydraulic (Paxnan 200hp) extinct 1968
D2708 etc - class D2/10 North British 0-4-0 diesel hydraulic (MAN 225hp) extinct 1968
D2900 etc - Class D3/1 North British 0-4-0 diesel hydraulic (MAN 330hp)
D2950 etc - Class D1/1 Hunslet 0-4-0 (same 153hp Gardner engine as the Barclay Class 01)
D2957 etc - Class D1/3 Ruston 0-4-0 (Rustion 165hp) extinct 1968
D2999 - Class D2/11 one-off Beyer Peacock/Brush 0-4-0 diesel electric (National of 200hp)
D3117 etc - Class 3/3 Crossley-engined variant of Classes 08/10:
D3152 etc - Class 3/5 Variant of Class 10 with BTH electrics:
12003 etc - Class D3/7 LMS design with jackshaft drive:
15000 etc - Class D3/9 LNER design,
15100 etc - Class D3/10 and D3/11: GWR designs
Even if you group classes with the same engine, wheel arrangment and transmission together (and that includes what became classes 03-05) you have fifteen classes to fit where there was only space for twelve.
For completeness, the other pre-TOPS shunter classes are as follows
D1/2 - Class 01
D1/4 - Class 02
D2/2- Class 03
D2/3 - ?
D2/4 - Class 04 (D2200-14)
D2/6 - Class 06
D2/8 - Class 05 (D2550-2573)
D2/9 - Class 05 (D2574-2618 - none of these received TOPS numbers as they were all withdrawn by 1968)
D2/13 - Class 04 (D2215-2341)
D3/2 - Class 08 and 09
D3/4 - Class 10
D3/6 - 12000 etc LMS 1936 design: all withdrawn by 1962
D3/8 - Class 11
D3/12 - SR design 15201 etc all withdrawn 1964
D3/13 - Class 12
D3/14 - 15004 LNER design with Brush engine, withdrawn 1962
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Merle Haggard
Established Member
Just wish there was all this information available when they were still about, could have appreciated things more.
But perhaps more knowledge would spoil the spotting fun; I saw a lot of Black Fives, even recorded 45401 at Northampton a few weeks before its demise (the first to be condemned - after a collision). What I didn't know then was that Crewe kept two spare Class 5 frames to speed up turnarounds so if one came into the works needing frame welding for cracking around the hornblocks ( a common problem) the loco leaving the works carrying that number would have a different, ex spare, frame (one off another loco previously in & already out the works and now repaired) - as well as different boiler and tender but possibly the same running plate, cab & smokebox. So I was fooling myself with what I was actually seeing.
A list of these codes appeared at the back of IA ABCs of diesels and the combined volume in the days before the 1968 scheme . They were described as 'Eastern Region Diesel Locomotive Classification' and were obviously based on the earlier G.N./L.N.E.R. system. Main line locos were also included, it's a long list! As an example - and to answer one of our questions - the basic B.R. '350' shunter was D3/1 and the engine/electrical variations were D3/1A, D3/1B etc. The first one or two digits were the hundreds of hp; the low power shunters using the 10s of hp - eg the 153 hp Hunslet/Gardners were 1/15, the 165 hp R&H 1/16 and the 170 hp YEC 1/17. Slight flaw in that D2953-6 although shown as 153 hp were 1/12 - were the engines in these de-rated - you might have expected 1/15A? But note that there were lots of gaps because the /nn no was significant not sequential. Don't go looking for the mysterious 1/1
Also, there was no D prefix to them.I have never ever heard anyone inside or outside the industry use them! - E.R. was the only English/Welsh region I never worked on, though.
norbitonflyer
Established Member
Thewre were several different systems used in the first twenty years of BR. So DEJ3 became D3/8 became 3/8A became Class 11
yeh but it makes for excellent bandwidth wasting wibble
So I will :
More speculative wibble, but if one looks at kettles than were still in traffic in 1968, it does more-or-less-but-not-exactly work that their 5 digit numbers fit -
9F 92000
8F 48000
7P6F 70000
4MT 75000
4MT 43000
5MT 44000/45000
5MT 73000
There was only a tiny duplication of those individual kettle numbers that were the same as diesel locos took up from 1973.
Pedants please note the more-or-less-but-not-exactly wording there is no need for lists and lists of every duplicate.
Of course, if steam had lasted longer, there may well have been more of the newer types around e.g.
4MT 76000
4MTt 80000
4MTt 42000
etc
Again there are few potential individual duplicates - and again there is no need to list everyones pet class that might have survived - or try and figure out how to deal with GWR locos *** - the point is overall few classes and few direct conflicts in 1968, and those that were could simply be shifted within their blocks - or - more simple - as kettle 5 digits already existed, ensure that renumbered diesels / electrics were in different ranges i.e. to avoid 76000 kettles then EM1 maybe 76501 upwards, and so on.
Before anyone dives in and says you can't have two types with one TOPS XX number - well they did - exactly upthread with series 05 that covered different types, same principle applies, just the loco types are more diverse.
Cue mountains of wibble ..................................... and anyway don't take this post /too/ seriously.
*** actually add a 9 prefix /almost/ solves it all
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Perhaps all this a reflection of the fact that BR did not come up with a 'future proof' numbering/classification system back in 1948/49, but rather opted for a simple renumbering based on adding some multiple of 10000 for the 'big 4', and leaving some 10000 number blocks free (some of which proided too many numbers, others too few), and no general reclassification ... one of my idle speculations is what such a scheme might have looked like.
yeh but it makes for excellent bandwidth wasting wibble
So I will :
More speculative wibble, but if one looks at kettles than were still in traffic in 1968, it does more-or-less-but-not-exactly work that their 5 digit numbers fit -
9F 92000
8F 48000
7P6F 70000
4MT 75000
4MT 43000
5MT 44000/45000
5MT 73000
There was only a tiny duplication of those individual kettle numbers that were the same as diesel locos took up from 1973.
Pedants please note the more-or-less-but-not-exactly wording there is no need for lists and lists of every duplicate.
Of course, if steam had lasted longer, there may well have been more of the newer types around e.g.
4MT 76000
4MTt 80000
4MTt 42000
etc
Again there are few potential individual duplicates - and again there is no need to list everyones pet class that might have survived - or try and figure out how to deal with GWR locos *** - the point is overall few classes and few direct conflicts in 1968, and those that were could simply be shifted within their blocks - or - more simple - as kettle 5 digits already existed, ensure that renumbered diesels / electrics were in different ranges i.e. to avoid 76000 kettles then EM1 maybe 76501 upwards, and so on.
Before anyone dives in and says you can't have two types with one TOPS XX number - well they did - exactly upthread with series 05 that covered different types, same principle applies, just the loco types are more diverse.
Cue mountains of wibble ..................................... and anyway don't take this post /too/ seriously.
*** actually add a 9 prefix /almost/ solves it all
I think it is only the Austrians who have a scheme that can look back to the 19th Century - despite a few changes to take account of the anschluss period, and computerisation, it is a clear development of that drawn up in 1904, which in its turn, was a development of that drawn on the formation of the kkStB in the mid 1880s. But it has still suffered from the issues I mentioned in my previous post.
If only we did have network electrification and loads of electric locos to have filled the 20000-29999 block ....................
The missing 38 & 39 is presumably simply explained that there were not enough different Type 3s to require them. Doesn’t explain the missing 49 - class 50s were type 4s!
where have you obttained the implication 3x must mean Type 3 or 4x must mean Type 4.
Merle Haggard
Established Member
At the time, what became Class 50s were widely known on the L.M. as 'Type 4 1/2s'...
thedbdiboy
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An entertaining thread which proves that whatever the intention originally, there was never any absolute consistency as to what constituted a sub-class, a new class or indeed how they should be numbered. Indeed the only constant once TOPS numbers were applied to locos (and later rolling stock) is that each item needs a unique number.
100 Class 86 (E3100) locos were built. By the time TOPS renumbering took place, 57 had been fitted with Flexicoil suspension and SAB resilient wheels; three were fitted with the forerunners of Class 87 bogies and associated equipment, and 40 remained in 'as built' condition. The as-built ones became 86/0 and numbered 86001-86040, the Class 87 fore-runners were classified 86/1 and numbered 86101-103. The remainder became class 86/2 but were numbered starting at 86204 onwards. neither 86/1s nor 86/2s ran in sequence with any of the old E31XX numbers so that decision was somewhat arbitrary. Later some of the remaining 86/0s became 86/3s when fitted with SAB resilient wheels, before all 86/0s and 86/3s became 86/4s, which were identical to 86/2s except that they had MU gear fitted. And that's all before some of them became 86/5s or 86/6s....
100 Class 86 (E3100) locos were built. By the time TOPS renumbering took place, 57 had been fitted with Flexicoil suspension and SAB resilient wheels; three were fitted with the forerunners of Class 87 bogies and associated equipment, and 40 remained in 'as built' condition. The as-built ones became 86/0 and numbered 86001-86040, the Class 87 fore-runners were classified 86/1 and numbered 86101-103. The remainder became class 86/2 but were numbered starting at 86204 onwards. neither 86/1s nor 86/2s ran in sequence with any of the old E31XX numbers so that decision was somewhat arbitrary. Later some of the remaining 86/0s became 86/3s when fitted with SAB resilient wheels, before all 86/0s and 86/3s became 86/4s, which were identical to 86/2s except that they had MU gear fitted. And that's all before some of them became 86/5s or 86/6s....
Merle Haggard
Established Member
It's often said that each number can only appear once on the TOPS system but I can say with certainty that wasn't the case.
When wagons were loaded onto TOPS - its original purpose, of course, being confined to freight - as cutover proceeded the prefix was ignored. The first of a new AB 35t glw type was 450000 - probably with a B prefix though this was not always carried by AB wagons. The LMS also built a batch of 3 plank open wagons, the first of which was numbered 450000. After 1948, it became M450000 and later very likely DM450000 as a spoil wagon.
To search for details of either wagon, 450000 was typed in (an F3 enquiry???) and I can say from personal experience that the details of one of the two wagons would appear, which one (they were quite different in characteristics) being apparently random - though it might have depended on which was most recently moved.
There could well have been many other duplicates, with series prefixed S, E, M, W and B all being independently created. the reason I made the enquiry was trying to locate the AB 450000 was for a display.
When wagons were loaded onto TOPS - its original purpose, of course, being confined to freight - as cutover proceeded the prefix was ignored. The first of a new AB 35t glw type was 450000 - probably with a B prefix though this was not always carried by AB wagons. The LMS also built a batch of 3 plank open wagons, the first of which was numbered 450000. After 1948, it became M450000 and later very likely DM450000 as a spoil wagon.
To search for details of either wagon, 450000 was typed in (an F3 enquiry???) and I can say from personal experience that the details of one of the two wagons would appear, which one (they were quite different in characteristics) being apparently random - though it might have depended on which was most recently moved.
There could well have been many other duplicates, with series prefixed S, E, M, W and B all being independently created. the reason I made the enquiry was trying to locate the AB 450000 was for a display.
TheHovisKid
Member
101 to 103 were briefly 201 to 203 as upthread, so those numbers not reused. AC locos and Peaks were renumbered as they went through works, others in order as they then were, not leaving gaps for losses and conversations before TOPS (mostly 27s, 31s, 33s and 47s?)
In any case, the E31xx numbers didn't reflect the build order.
86s had two types of motor ignoring 101 to 103) with /2 beings a little more powerful? Hence they remained separate (apart from the brief /5 first time round) from the others.
Conversations between /0 /3 /4 and /6 retained the last two numbers and wasn't MU dependant, lots of /0 had it, don't think 316 did
thedbdiboy
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They had the same axle-hung traction motors but unmodified 86s (86/0s) were restricted to 80mph because of the wear that these caused to the track. The Flexicoil suspension and SAB resilient wheels that 86/2s had allowed them to work to 100mph. The weren't fitted with MU equipment either (although later gained TDM jumpers for DVT propulsion).
12LDA28C
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Apart from the obvious exceptions (Class 20s being Type 1, Class 31s being Type 2, etc).
TheHovisKid
Member
282AZ @ 900 hp in some (became 0, then maybe 3, all 4, some 6)
282BZ @1,000 hp in the ohers (2, some 5 briefly)
412AZ @ 1250hp in the 87s, bar 101 which had BZ
Are the 08/0s not also an eclectic mix of train braking systems - I am reasonably confident that vacuum only, air only and dual all exist. I can’t recall how much this was true ex-factory however it would be an obvious sub class differentiator as it directly affects their tasking.The 90v vs 110v distinction in the large D.E. shunters seems to have been relevant to condemnation decisions. Around 1970 I used to see the stock changes lists which gave reason for condemnation and, for the D.E. shunters, it was either 'run-down condition' or 'xx volts'. This voltage was always the same, I think that it was the 90 variation but I'm not sure.
I kept (somewhere but can't find) an article about B.R. D.E. shunters in a trade magazine I used to see in the 1960's - I think it was called The locomotive Engineer. This referred to the rating being 400 h.p. (in most cases) but also some were 430 h.p. (or maybe 425??) . Shattered my faith in the accuracy of Ian Allan's A.B.C.s
randyrippley
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I've always assumed class 49 was DP2, and that 51 was Lion, 54 was DELTIC
also I'd assumed
38 = 10201-2
39 = 10203
36 = 10000-1
It's always seemed peculiar to me that classes 21, 22, and 42 were not split across subclasses: all had modernisation-era trial/pre-production batches which varied from the main production batches. Different versions of the diesels, different alignment of the transmissions, different gearbox ratios, different power outputs.
Another anomaly are the Peaks, where the modernisation-era trial batch (class 44) got not a different subclass, but a complete class to itself (vs class 45 for the main production). This is the only design where this happened. Anybody know why? What were the differences which made it necessary to split the 44s out? It can't be different power settings - as that wasn't regarded as relevant in the hydraulics.
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Merle Haggard
Established Member
No '350' was built with air brakes.
Many of the early ones did not have vacuum brakes and as a result did not have the large, louvred locker towards the front - though, in another example of 'the more you find out the less you know' some unfitted shunters did have them. Looking at both sides of the same shunter made the builders' logic even more inscrutable...
== Doublepost prevention - post automatically merged: ==
Indeed, sorry, remember now. Makes the 47 - 50 jump inexplicable
Regarding our exchange about The Book of the Warships, my previous regard for it as an accurate source of information has been demolished because I've just noticed that the cover bears the subtitle '(The Western Region D600/D800/D833 Class 41/42/43 diesel hydraulics)'. Doh!
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