Class 87

The Class 87 was built for the extension of the electrification of the West Coast Main Line into Scotland and was Britain's first 5, 000hp locomotive [1]. The Class 87 was a development of the then standard AC electric locomotive the Class 86 and shared the same body shell but with redesigned bogies with Flexicoil suspension to reduce track wear [2] and frame mounted traction motors. The Class 87s were cleared to travel at up to 110 mp/h.

Number built: 36
Built: 1973-75
Builder: BREL Crewe / GEC Traction
Engine: 4 GEC G412AZ traction motors
Power: 5, 000 hp (3, 728 kW)

Thirty five Class 87/0s were built with a 36th locomotive being the solo Class 87/1 which tested a thyristor control system. The later Class 90 was a development of the 87 and indeed was at one stage to have been the Class 87/2. A small number are still in operation on the main line and some have been preserved. Quite a few have been exported to the continent and serve in Eastern Europe [3].
87 001 at the NRM

87 035 at Crewe Heritage Centre

Cab of 87 035

[1] Chris Heaps, BR Diary 1968-1977 (Ian Allan, 1988), p. 70
[2] Brian Haresnape, Electric Locomotives (Ian Allan, 1983), p. 69
[3] Colin J. Marsden, Traction Recognition (Ian Allan, 2008), p. 88

Class 73 [Updated]

Despite the fact that diesel locomotives often spend a fair amount of time operating along electrified routes it is unusual that British Rail only ever built 2 classes of electro-diesel locomotives that could operate both as electric or diesel locomotives. Both were based on BR's Southern Region of which the Class 73 is the only survivor [1]. A growing number have been rebuilt and upgraded in the last few years so they look set to remain in service for a long time to come.

The Class 73 is an electric locomotive designed to work with SR's 660-750v DC third-rail system. It also has a small diesel engine for operating on non-electrified lines or if the power is off. They are highly versatile locomotives that have served on a whole range of traffic in Southern England, being true mixed traffic locomotives they could be found on passenger and freight services. Their numbers were steadily reduced in the privatisation era.

Number built: 49, 11 re-engineered
Built: 1962 1965-67, Re-engineering from 2013-16
Builder: BR Eastleigh / English Electric
Re-engineering by RVEL Derby & Brush Traction
Engine: English Electric 4SRKT Mk II diesel
EE542A or EE546/1B traction motors
Re-engineered examples with 2 Cummins QSK19 or 1 MTU V8 diesels
Power: 1, 420 hp (1, 059 kW) - Electric
600hp (447kW) - Original EE diesel
1, 500hp (1, 119 kW) - Cummins
1, 600hp (1, 194 kW) - MTU

In the last couple of years however there have been 2 separate re-engining efforts to create the rebuilt 73/9 sub-class [2] (at one stage it was considered creating a new Class 75 but would have cost more in administration and re-certification [3]). The work includes replacing the original EE diesel with a much more powerful motor and replacing worn electrical and mechanical components. Eleven have been re-engineered to date in 2 phases. The "Phase 2" Class 73s with MTU diesels have had their third rail equipment removed [4]. As virtually "new" locomotives they will likely serve with Network Rail and other operators for a long time to come (they are expected to last at least 25 years). A number have also been preserved.

Sub-class Details
73/0 Original prototype batch, originally to have been called the Class 72
73/1 Main production batch, higher power output and speed
73/2 Modified for Gatwick Express push-pull duties (coupled to the Class 488 and 489)
73/9 Re-engineered and upgraded examples
73 952 at Kidderminster SVR

GB Railfreight 73 136 at Clapham Junction
Sideways view of 73 952

[1] Colin J. Marsden, Traction Recognition (2nd Edition) (Ian Allan, 2008) p. 82
[2] "Projects", RVEL <>
[3] "Re-engineered/tractioned 73s", WNXX Forum <>
[4] "Caledonian Class 73 contract nears end", Today's Railways UK, March 2016, p. 32

Class 143

The Class 143 was built at the same time as the Class 142 and is also a railbus design marrying a bus or coach type body (built by coach builder Walter Alexander) to a chassis derived from a freight vehicle. The Class 143 perhaps look a bit more like a train however compared to the 142, the body of which retained more aspects of its Leyland National bus heritage.

Number built: 25 2-car sets
Built: 1985-86
Builder: Walter Alexander / Andrew Barclay
Engine:Cummins LTA10-R per car
Power: 450hp (330kW)
Formation: DMS (Driving Motor Standard)+DMSL (Driving Motor Standard Lavatory)

Originally the 143s worked for British Rail's Provincial Sector and the Tyne & Wear PTE. In the privatised era they are operated by First Great Western (GWR) and Arriva Trains Wales. Like the 142s their original transmission has been replaced with a Voith hydraulic one. As with the other railbus designs the 143s are probably in their final years now with withdrawal planned for the end of the decade.
ATW 143 614 at Cardiff Central

ATW 143 606 at Cardiff Queen Street

Class 377 [Updated]

The "Electrostar" Class 377 is the largest fleet of EMUs built since rail privatisation and has replaced 4-Cig and 4-Vep EMUs on commuter services around London and rural services in the South East. Although their class number is in the 3xx series most collect electric current via the 750v DC 3rd rail system though some have pantographs. These can also collect current from 25kV AC overhead lines for cross-London services and can venture up as far as Milton Keynes and St. Albans. Some Class 377s have been converted from the similar Class 375 as detailed below.

Number built: 211 sets (plus 28 sets converted from Class 375)
Built: 2002-
Builder: Bombardier Derby
Engine: 6 or 4 Bombardier traction motors
Power: 2, 120 hp (1, 500 kW) or 1, 341 hp (1, 000 kW)
Formation: Driving Motor Composite Open (DMCO)+Motor Second Open (MSO)+
Trailer Second Open (TSO)+DMCO

They are in service with Southern and Thameslink and more will be built over the next few years. The fleet is split into a number of sub-classes.

Sub-class Details
377/1 Original, third-rail DC 4-car operated by Southern
377/2 Dual voltage 4-car operated by Southern and Thameslink
377/3 Third rail DC 3-car units converted from Class 375s operated by Southern
377/4 Third rail DC 4-car operated by Southern
377/5 Dual voltage 4-car operated by Thameslink
377/6 Third rail DC 5-car operated by Southern
377/7 Dual voltage 5-car operated by Southern

Southern 377 612 at London Bridge

Southern 377 440 at Clapham Junction

Southern 377 701 at West Brompton