BR Std classes numbering

One thing I have always wondered about, with the numbering of the std classes, why weren't certain number series used eg: 74xxx, 79xxx, 81xxx, 85xxx etc

Were these number series reserved for proposed designs that never left the drawing board?

 

Or possibly to leave room for classes they thought they might build more than 1,000 of... Goodness knows they had enough classes as it was...


[half a day Later]
- 72/3xxx - presumably would replace 330 Halls, 800 odd Black 5, 600 odd Bx.
- 78/9xxx - might just have been to start the tanks at 80000
- 80/1xxx - presumably 300 odd GWR large prairies, 500ish LMS 4MT, plus various LNER and SR large tanks.

Both of those seem good for over a thousand once the pre nationalisation classes were extinct around the 1980s or 90s... Which, I submit tells us a lot about the quality of planning from the Riddles team if they really thought steam might last that long...

 

And starting at zero, e.g. 70000. When you start to number something you start at one, not zero, don't you?

 

The GWR and LMS did it and probably a lot of the other companies did it as well.

 

The early diesels numbers ended in zero ie 5500, 9000 etc wasn't until TOPS came along that numbers ended in 001.

 

But he didn't have the foresight to leave room at the start for the 9Fs which ended up consigned to the WD series?

 

Or so it fits the pattern:
7xxxx = Passenger/mixed traffic tender engines (only 71000 can be described as a purely passenger engine)
8xxxx = Mixed traffic tank engines
9xxxx = Freight engines (whilst the WD 2-8-0s weren't built by BR, they serve the purpose of a BR standard 8F hence why BR didn't built any)

 

I often think that, prior to TOPS numbering, enthusiasts have always been more concerned about numbering systems than the railway companies ever were!

 

Yes but... Its what happens at the other end.
The GWR used to start classes at xx01, but when they built the hundredth it got a bit confusing - eg 2701 to 2800 were 0-6-0ST, 2801-> were 2-8-0 freight. So they started numbering classes from xx00.

I don't know about that, in spite of the potential disruption to records of renumbering they all did it from time to time, sometimes with peculiar results. Holcroft has quite a bit to say about SR renumbering after the Grouping.

Another example: when the GWR absorbed all the Welsh lines they carefully numbered the loco stock in groups with locomotives of the same wheel arrangement together, and then, it seems, locomotives of the same power and boiler pressure. Quite logical, in terms of having locomotives of similar capability grouped together.

Except that some classes were split apart because some locos on some lines had old boilers running at reduced pressure, which Swindon wouldn't stand for so repaired the boilers properly and ran them at design pressure. Then they started a program of reboilering with GWR boilers, so within a few years the carefully sorted groups were pretty much meaningless...

 

Referring to Jimc's "half a day later" post above, I have just had a quick read of "British Railways Standard Steam Locomotives" by E S Cox, a book that I would consider as the definitive work on the 12 new Standard classes. Cox appears to be silent on the actual numbers to be built, and whether as they were built that older similar pre-nationalisation types would be taken out of service.
In some cases there was a shortage of suitable loco types, but with others the idea was certainly to allow the scrapping of many very much older types.
In fact from 1948 to 1954 bear in mind that some 1550 new locomotives were built to existing pre-nationalisation specification, alongside the new Standards.
Given that only 999 new Standards in total were built I doubt that the gaps in the numbering system, ie no "81xxx" locos, was in fact leaving room for more than 1000 of any one class to be built.
The only cancellations mentioned by Cox are the 15 further "Clan" 4-6-2's, and a batch of ten class 4 4-6-0's ( presumably 75xxx) for the Eastern Region, but were further batches of other Standards cancelled? Can anyone help with this?

46118.

 

I doubt more were cancelled, but I'm sure many planned were not authorised.

 

77020-24 and 82045-62 were cancelled. They are mentioned on quite a few drawings.

 

The pre nationalisation types would certainly come out of service eventually, so there was no good reason not to leave room in the numbering scheme for their eventual replacements, whether they would be required in 1967 or 1997. Its not as if there's really a downside in leaving large gaps if you have a big enough number space. In my own experience (with private IP addressing) I've run into much more awkwardness where gaps between different series were too small than I have where there were large gaps between series.

 

Thinking off the top of my head my thoughts are that the classes beginning with 74000 and 91000 were proposed classes that never happened. Classes 81000 and 83000 were I suspect just tactical gaps should a new class have been introduced at some point. See below for a full breakdown.

Passenger Classes

70000, 71000, 72000, 73000 all allocated
74000 could have been the proposed Class 5 with the crosti boiler?
75000, 76000, 77000, 78000 all allocated
79000 onwards unallocated

Tank Engines

80000 allocated
81000 spare (future planning?)
82000 allocated
83000 spare (future planning?)
84000 allocated
85000 onwards unallocated

Freight Engines

90000 WD Classes
91000 Proposed 2-8-2
92000 allocated
93000 onwards unallocated

Paul

 

quite clearly had things continued there would have been more than a thousand 73xxx running into the 74xxx series.



Events overtook Steam (inevitably) and it never became a problem.

Having planned quite sensibly for steam, they then rather cocked it up for diesels.

 

79XXX were various types of DMUs built in the mid fifties.

 

different series altogether and prefixed with a regional letter

 

That's the carriage and multiple unit numbering system, separate from the loco numbering.

 

It depends.....

In mathematics and computing (the latter essentially growing out of the former), the number zero is a perfectly acceptable entity in its own right. A decimal number system can represent ten distinct entries through the use of 0 to 9 (the number 10 being the first entry of the second 'block' so to speak. The hexadecimal system (the base of all computer programming) features 16 distinct entries (0 to 9, then A to F) before you start the next set of 16 entries at 10. In a binary system you can only represent two entries, 0 and 1 before getting to 10.

As such having new railway platforms described as "Platform Zero" is not as daft as it first sounds and neither would be a locomotive numbered 0.

Its only really when you start getting into the realms of what might be described as 'human perception' does zero not seem a logical number because we associate the number 0 with nothing.