British Rail Class 73 facts for kids

The British Rail Class 73 locomotives are special trains that can run in two ways! They are called electro-diesel because they can get power from electric rails or from a diesel engine. This makes them very useful because they can travel on tracks that have electricity and also on tracks that don't.

Quick facts for kids British Rail Class 73
Class 73, no. 73201 at Woking. This locomotive was used by South West Trains as a “Thunderbird” to rescue failed trains.
Type and origin Power type Electro-diesel Builder 73/0: British Railways’ Eastleigh Works 73/1: English Electric at Vulcan Foundry Build date 1962, 1965–1967 Total produced 49
Specifications Configuration: ​  • Whyte Bo-Bo  • UIC Bo'Bo' Gauge 4 ft 8 1⁄2 in (1,435 mm) Wheel diameter 3 ft 4 in (1.016 m) Length 16.36 m (53 ft 8 in) Loco weight 73/0: 76.30 long tons (77.52 t) 73/1: 76.80 long tons (78.03 t) Electric system/s 660–750 V DC Current pickup Third rail Prime mover English Electric 4SRKT Mk II Traction motors 73/0: EE 542A 73/1: EE 546/1B Train heating Electric Train Heating Train brakes Vacuum, Air and Electro-Pneumatic
Performance figures Power output Electric (continuous): 1,420 hp (1,059 kW) Electric (one-hour): 1,600 hp (1,193 kW) Engine: 600 hp (447 kW) Tractive effort 73/0 (electric): 42,000 lbf (186.8 kN) 73/0 (diesel): 34,100 lbf (151.7 kN) 71/0 (electric): 40,000 lbf (177.9 kN) 73/1 (diesel): 36,000 lbf (160.1 kN)
Career Axle load class Route availability 6

Class 73, no. E6013 (73107) at Rowsley South, on the Peak Railway on 17 April 2003. This locomotive was on loan from Fragonset Railways, and has since returned to main-line service.

Class 73/1 73101 in BR blue livery

About the Class 73 Train

The Class 73 is a very special type of train called an electro-diesel locomotive. This means it can use two different ways to get power. It can run on electricity from a special third rail, or it can use its own diesel engine.

How it Works: Electric Power

When the Class 73 is on tracks with a third rail, it gets its power from there. This is a common way for trains to get electricity in some parts of Britain, especially in the south. Using electric power makes the train very strong and fast.

How it Works: Diesel Power

If the train needs to go on tracks that don't have electric power, it can switch to its diesel engine. This engine lets the train travel anywhere, even on lines that aren't electrified. However, the diesel engine isn't as powerful as the electric motor. This is why these trains usually stay on routes that have the third rail.

Why it's Unique

The Class 73 is the only train of its kind still running in Britain. Before 1977, there was another type of electro-diesel train, the Class 74. But after those were retired, the Class 73 became truly unique. Its ability to switch between electric and diesel power makes it very flexible for different railway lines.

Who Used These Trains?

Many different railway companies have used the Class 73 over the years. Some of them include:

• British Rail
• Eurostar
• Gatwick Express
• Network Rail
• South West Trains

These trains have been used for many jobs, from pulling passenger trains to rescuing other trains that have broken down.

Images for kids

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  A British Rail Class 73 with a parcels van and carriages under British Rail carrying the mail in 1986 through Clapham Junction.

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  Dover Western Docks Sidings in 1982 under British Rail.

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  Eurostar Class 73 73130 at Finmere in preservation hauling 4CIG 1753 on an open day at this former Great Central station site in 2016.

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  73211 with a Gatwick Express train at Horley in April 2001.

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  73107 is on display at Long Rock Depot open day, along with freshly painted 50049 and 50007.

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  73966 in Caledonian Sleeper livery at Fort William Station.

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  No. 73951 (previously 73104 and E6010) at Eastleigh works on 31 October 2015 following conversion to Ultra73 specification.

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  No.E6006 in preservation at Bridgnorth on the Severn Valley Railway

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  73210 and 73136 at Dereham on the Mid-Norfolk Railway