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Rail Data > Data > Codes
Codes Index
The lists in the Codes section are (perhaps unsurprisingly) to do with the codes used to convey information about items of rolling stock. Each list can be accessed using the menu on the left, or the links in the table below, which also gives an outline of what is included.
TOPS / Class
The TOPS computer system was introduced by BR in the early 1970s and brought in a whole new array of type classifications. Locos and multiple units were given numerical classes, while wagons had alphabetic codes (referred to as TOPS codes). The list on this page includes all known TOPS class and type codes. The list includes sub-codes such as loco and multiple unit sub-classes and wagon sub-codes.
Designs /Diagrams
The list on this page is to do with the technical classification of rolling stock. Prior to the advent of the TOPS computer system, rolling stock to any particular design was allocated a common diagram number. TOPS brought in a more detailed breakdown of variations, the most detailed being known as design codes. Separate classification schemes were used for international rolling stock. Also included in this list are some of the diagrams used by the pre-nationalisation companies, with more to be added over time.
Pools
The introduction of sectorisation to BR during the 1980s saw all rolling stock being allocated to a given pool for accounting purposes. Four-letter codes were used, where the first letter indicated the owning sector and the other three giving details about the depot and/or traffic allocation. Similar codes had already been in use for wagons for some time, though these were made up of more numerical digits. The list on this page includes all known pool codes. Because the meaning of a given code could (and did often) change over time, the main list shows only the most recent definition for each code. Earlier definitions can be found by viewing the pool detail page.
Locations
Most rolling stock is allocated to a 'home' depot, responsible for its basic maintenance. In the steam and early diesel era, BR had shed codes made up of two digits and a number (eg 52A). Under TOPS these were replaced by 2-letter codes (eg GD). Codes in both series were liable to be changed and re-used. Because of this, the main list here is based on the name of the location rather than its coding. Wagons were not generally allocated to a particular location, although they would be allocated to a pool.
Prefixes
A lot of rolling stock carried prefix letters in front of the stock number, these normally indicated the owning region, department or company. Any single prefix could have different meanings, depending on what type of stock it was applied to. For example, an M-prefixed coach would be one allocated to the London Midland region, while an M-prefixed wagon would be one that had been inherited from the LMS, or (later on) a wagon owned by Mainline Freight. Prefixes were often changed, so a lot of the data on this website omits them, referring just to the numerical portion. The list on this page show all known codes and what they indicated.
Fishkinds
This curiously-titled page lists all known codes in the 'Fishkind' series. For many years BR used the names of different types of fish to differentiate different types of engineers wagons, this simplifying the specification of train requirements in telegraphs and so on. The system remains in use to this date, although some of the remaining codes are not actually painted on the wagons involved. It is also notable that the scheme has been expanded to include animals other than fish (for example Heron and Osprey).
Coach Types
All coaching stock on BR (including those formed into multiple units) is allocated a type code based on a combination of letters which describe the key features. These ranged from a single letter (e.g. C for Composite) up to six or seven letters (e.g. a BDTSOL was a Battery driving Trailer Second Open with Lavatory). The list on this pages shows all known codes and what they meant.
Liveries
This page (not yet available) will list the various standard liveries applied to rolling stock over the years.
Dimensions
This section is not really to do with codes but I couldn't think of anywhere better to place it. This page lists a variety of dimensions for selected rolling stock. In most cases the information is related to a particular diagram or design code, and the information can also be found by looking at the design detail page. Relatively few dimensions have been inputted so far but many more will be done in due course.
Drawings
Another section that doesn't really fit anywhere better. This is not actual drawings, but references to where drawings can be found. These can be in books, magazines or on other websites. Drawings are linked to a particular type or design in the database, and an indication is given of the level of detail in the drawing and which views (i.e. plan, side, end) are included. As with the dimensions, not many have been entered as yet, but it is hoped to add many more soon.