British Rail Wiki

Total Operations Processing System, or TOPS, is a computer system for managing the locomotives and rolling stock owned by and/or operated on a rail system. It was originally developed by the American-based Southern Pacific Railroad and was widely sold; it is best known in Britain for its use by British Rail (BR) and its successors.

The main parts included: Locomotive/ Unit Numbers, Coach Numbers, Wagon Numbers, Coach Coads, Wagon Coads and Headcoads.

Sample Output[]

This is a typical report that a TOPS clerk could generate. The train in question is a 25 wagon freight train travelling from Over & Wharton, near Winsford, to Reading West Junction, Berkshire.[1]

K383400 0010 2837 22/10/86 U483 ON N199 BY KO
LOCO       25901
LOCO       25908
37015 OVER&WHAR                         1520     025 000    71212
65700 BESCOTYD    NRP        1707 EST   1709 EST 025 000
74260 READINGWJ  DETAIL      2007 EST            025 000


Each locomotive and Wagon had a number and a TOPS Pannel, meaning a driver, shunter or gaurd could tell what was to make up there train. Here are some images of TOPS Pannels:


Class Range Type Horsepower Previous Numbers Image
01 - 07 Shunters Under 300 D2000 - D2999
08 - 13 300 - 799 D3000 - D4999
SAM 0458.JPG
14 - 20 Type 1 800 - 999 D9500 - D9999, D8000 - D8999
21 - 31 Type 2 1000 - 1499 D5000-D6499, D7500-D7999
SAM 0014.JPG
33 - 38 Type 3 1500 - 1999 D6500-D7499
40 - 54 Type 4 2000 - 2999 D1-D1999
SAM 0602.JPG
55 - 60 Type 5 Over 3000 D9000-D9499
70 - 74 DC Electrics
76 - 93 AC Electrics
SAM 1012.JPG
97 Departmental
98 Steam
SAM 0032.JPG
99 Ships

Multiple Units[]

Each unit was made up of a certain amount of Coaches with there individual designations. Here are the main range:

Class Type Image
100-114 Diesel-Mechanical 'Low Density' passenger units (i.e. few doors per carriage) - mostly short (57'0") frame, but Class 114 are long
SAM 2180.JPG
115-127 Mixture of 'High Density' (i.e. doors to every seating bay) and 'Cross-Country' (long distance) passenger units - long (63'6") frame
128-131 Parcels units - mostly long frame, but Class 129 are short
140-144 Second generation railbus (4-wheel) units ('Pacer')
150 - 159 Second generation bogie units, Sprinter
165 - 166 Second generation bogie units Networker
200-207 Diesel-Electric First generation units
253 - 255 Express units
300-312 AC Electric First generation units
313 - 325, 334, 365 Second generation units
370 Express units
SAM 1022.JPG
920-935 Departmental units Southern Region departmental units
936-939 Other departmental electric multiple units
950-960 Other departmental diesel multiple units (since the privatisation of British Rail, this series has included electric multiple units)

AC electric multiple units AM1-AM11 became 301-311 in order (in fact the AM1 units had already been withdrawn, so Class 301 was never actually used). The 1xx and 2xx series were originally arranged so that driving motors, driving trailers and trailer cars all had their own individual class numbers (presumably because these units were more prone to being reformed), but this was subsequently revised so that each type of unit had a single class number, as allocated to the driving motor car.

Whereas within most ranges class numbers were allocated sequentially as new types were constructed, the Southern Region adopted a more complicated system for their electric multiple units, with the second and third digits indicating in more detail the type of unit. Second digits were allocated as follows:

Class Type
40x Southern Railway-designed units
41x 1950s British Railways-designed units
42x 1960s British Railways-designed units
43x 1967 Bournemouth Electrification units
44x 1970s British Railways-designed units
45x 1980s British Railways-designed units
46x 1990s Networker units
48x Underground ('Tube'-sized) units
(also temporary formations and, later, 'Gatwick Express' units)
49x Unpowered trailer units (later 4x8)

Third digits were allocated as follows:

Class Type
4x0 Express units with buffet (later 4x2)
4x1 Express units
4x3 Four-car outer-suburban units
4x4 Two-car outer-suburban units
4x5 Four-car inner-suburban units
4x6 Two/three-car inner-suburban units
4x7 Special purpose units (e.g. first 'Gatwick Express' units)
4x9 Single car units

Coaches & Wagons[]

A: Hauled passenger carriages
B: Bogie Steel wagons (excluding coil-carrying wagons until 1984[2])
C: Covered bulk wagons (except CA: goods brake vans)
D: Diesel Multiple Unit carriages
E: Electric Multiple Unit carriages
F: Flat wagons
G: High Speed Train carriages
H: Hopper wagons
I: Ferry wagons (International wagons)
J: Private owner bogie wagons (bogie steel coil wagons until 1984[2])
K: Private owner special wagons (2-axle steel coil wagons until 1984[2])
L: Advanced Passenger Train carriages (includes Eurostar and Siemens Velaro)
M: Mineral wagons
N: Hauled non-passenger carriages
O: Open wagons
P: Private owner 2-axle wagons (originally all private owner wagons)
Q: Hauled departmental (non-revenue) carriages
R: Railway operating vehicles: Barrier wagons, Adaptor wagons, Runners and Diesel Brake Tenders
S: 2-axle steel wagons (excluding coil-carrying wagons until 1984[2])
T: Tank wagons
U: International hauled coaching stock (Uncovered bulk wagons until 1984[2])
V: Vans
W: Flat wagons
X: Unused (Exceptional and Special use wagons until 1984[2])
Y: Departmental bogie wagons
Z: Departmental two-axle vehicle (carriage or wagon)

The second letter gave more detailed information, different for each series. The tables below list the variations for carriages:

   A Series
AA: Corridor
AB: Brake Corridor
AC: Open (2+2 seating)
AD: Open (2+1 seating)
AE: Brake Open
AF: Driving Brake Open
AG: Micro-Buffet
AH: Kitchen Buffet
AI: Open (2+2 seating) - end of Mark IV rake
AJ: Restaurant Buffet
AK: Kitchen
AL: Open (2+2 seating) - with disabled persons' toilet
AM: Restaurant
AN: Miniature Buffet
AO: Private Owner
AP: Pullman Kitchen
AQ: Pullman Saloon
AR: Pullman Brake
AS: Sleeping
AT: Royal Train
AU: Sleeping (with pantry)
AV-AY: Barrier vehicles
AX: Generator Van (Until 1987: Narrow gauge)
AY: (Until 1987: Narrow gauge Brake)
AZ: Special saloon
   D and E Series
xA: Driving Motor
xB: Driving Motor Brake
xC: Non-driving Motor
xD: Non-driving Motor Brake
xE: Driving Trailer
xF: Battery Driving Trailer
xG: Driving Trailer Brake
xH: Trailer
xI: Battery Driving Motor
xJ: Trailer Brake
xN: Trailer Buffet
xO: Battery Driving Trailer Brake
xP: Driving Motor (Diesel Mechanical Multiple Unit only)
xQ: Driving Motor Brake (Diesel Mechanical Multiple Unit only)
xR: Non-driving Motor (Diesel Mechanical Multiple Unit only)
xS: Driving Trailer (Diesel Mechanical Multiple Unit only)
xT: Trailer (Diesel Mechanical Multiple Unit only)
xU: Trailer Brake (Diesel Mechanical Multiple Unit only)
xX: Non-passenger Driving Motor and single-car passenger DMMUs
xY: Non-Passenger Non-driving Motor
xZ: Departmental stock
   G and L Series
xC: Motor
xE: Driving Trailer
xF: Barrier Vehicle
xH: Trailer
xJ: Trailer with Guard's compartment
xK: Trailer Kitchen with Buffet
xL: Trailer Kitchen
xM: Trailer Kitchen with Lounge
xN: Trailer Buffet
   N Series
NA-NI: Gangwayed Brake vans
NF: Brake van (non-gangwayed)
NG: Car-carrying flat wagon
NJ-NK: General Utility van
NL-NM: Newspaper van
NN: Courier vehicle
NO-NQ: Parcels van
NR: Container van
NS: Post Office Sorting van
NT: Post Office Stowage van
NU: Post Office Stowage Brake van
NV: Car-carrying van
NW: Bullion van
NX: Motorail van
NY: Exhibition van
NZ: Driving Van Trailer
   Q, Y and Z Series
xA-xC: Ballast and sleeper wagons
xD: General materials wagon
xE: Runner wagon
xF: Ballast hopper wagon
xG: General materials wagon
xH: Spoil wagon
xI: Crane
xJ: Tracklayer
xK-xM: Ballast wagon
xN: Steel wagon
xO: Crane (travelling)
xP: Staff or dormitory vehicle
xQ: Tool vehicle
xR: Stores or materials vehicle
xS: Operating vehicle (e.g. barrier, generator)
xT: Brake van
xU: Brake van plough
xV: General equipment vehicle (e.g. flat wagon)
xW: On-track plant, saloon or self-propelled vehicle
xX: Specialist equipment vehicle
xY: Electrification equipment vehicle
xZ: Miscellaneous vehicle (e.g. snowplough, unpowered former locomotive)

The final letter indicated the braking arrangements. Nowadays almost all stock is air-braked, but when TOPS was introduced there was much greater variety, which made marshalling trains more complicated and this information essential. The letters were:

A: Air brake only
B: Air brake plus through vacuum pipe
D: Electronic control
E: Electro-pneumatic brake
F: Vacuum brake (AFI equipment) [AFI: Accelerator Freight Inshot - a rapid-acting vacuum brake[3]]
G: Vacuum brake plus through air pipe (AFI equipment)
H: Dual brake (AFI equipment)
O: Unfitted (handbrake only)
P: Unfitted with through vacuum pipe
Q: Unfitted with through air pipe
R: Unfitted with through air and vacuum pipes
V: Vacuum brake only
W: Vacuum brake plus through air pipe
X: Dual brake (air and vacuum)
Y: Unfitted (Civil Engineer's self-propelled stock)
Z: Automatic brake of unknown working order[3]


  1. South Devon Railway newsletter 8
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Marsden, Colin J. (1984). BR and Private Owner Wagons. Rolling stock recognition. 2. Shepperton: Ian Allan. p. 6. ISBN 0-7110-1403-5.
  3. 3.0 3.1 Hendry, Robert (2003). British Railway Goods Wagons in Colour 1960-2003. Hinckley: Midland Publishing. p. 94. ISBN 1-85780-170-9.