Wagon TOPS codes

TOPS (Total Operations Processing System) was introduced by BR in 1972 to improve the management and control of its rolling stock.  Previously wagons had a telegraph code name, although traffic vehicles lost there code names with the introduction of TOPS engineers vehicles retained theirs alongside their TOPS Code.  Under TOPS each wagon or coach is allocated a four letter code although only the first three letters are displayed on the vehicle.  The code is broken up into the following subtypes.

CKINDX - first 2 characters
GENKOC - first character (i.e. ZUV)
BRAKTY - third character (i.e. ZUV)
CARKND - TOPS displayed code (three letter code)
AARKND - Fourth character (not displayed on stock)

The letters are defined as follows:

First Character (GENKOC)

A. coaching stock - passenger carrying
B. bogie steel carrying
C. covered (bulk carrying), also revenue brakevans
D. diesel multiple units
E. electric multiple units
F. flat wagons
G. high speed trains
H. hoppers
I. internationally registered vehicles
J. bogie private owner wagons (was Bogie steel coil)
K. bogie special wagons (was 2-axle steel coil)
L. previously allocated to APT stock (R.I.P.)
M. mineral wagons
N. non-passenger carrying coaching stock
O. open wagons
P. privately owned 2-axle wagons
Q. departmental coaching stock
R. railway operating vehicles
S. 2-axle steel carrying wagons
T. private owner tanks
U. nightstar (EPS) stock, previously allocated to uncovered bulk carriers
V. vans
W. miscellaneous wagons
X. not in use, previously allocated to special wagons
Y. bogie departental vehicles and track machines
Z. 2-axle departmental wagons

Second character

Defines the above codes into particular types

Third character (BRAKTY)

A. air braked only
B. air brakes and vacuum piped
F. vacuum brake (AFI type)
G. vacuum brakes (AFI type) and air piped
H. dual air and vacuum (AFI type) brake
O. unfitted (handbrake only)
P. vacuum piped
Q. air piped
R. dual air and vacuum piped
V. vacuum brake only
W. vacuum brake and air piped
X. dual air and vacuum braked
Y. unfitted (self propelled civil engineers vehicles)

Fourth character (AARKND)

Supplements the CARKND code, allowing the identification of specific variations of wagons. The letter is not used on the actual wagons, but only appears on computer records and offical diagrams.

Wagon number prefixes

In addition to a TOPS code and number many vehicles had and have a prefix to the number to identify their ownership.  All traffic wagons built by British Railways/British Rail after nationalisation and prior to the introduction of air braked were all prefixed with a 'B' while air barked vehicles in revenue service have no prefix.

Numbers on traffic wagons which were absorbed from the big four were prefixed with 'E' for LNER, 'M' for LMS, 'S' for Southern and 'W' for GWR.

Departmental vehicles prefix this initial builder perfix letter with a 'D' giving: 'DB' BR built departmental, 'DE', 'DM', 'DS' and 'DW'.  Air braked BR built vehicles carry a 'DC' prefix.

Finally departmental affiliation, ownership, is shown by another third prefix letter.  These are shown in the list below, if the third letter is absent the vehicle belongs to the civil engineers department.

A-- Mechanical & Electrical Engineer (M&EE)
B-- British Rail Telecommuncations (BRT)
C-- British Rail Engineering Ltd. (BREL)
K-- Signal & Telecommunications Engineer (S&TE)
L-- M&EE Electrical Construction Deptartment
R-- Research Department
T-- Traffic Department
Z-- Public relations and Publicity

Thus following this convention is can be seen that SEng's Rectank ADB531001 is a BR built wagon which was allocated to departmental use for the Mechanical & Electrical Engineer.

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Last modified: 11/30/02