Class 20 diesel locomotives were built in 1957-1968 by English Electric as Type 1 and they are known by railway enthusiasts as “Choppers“, a name derived from the distinctive beat that the engine produced when under load which resembles the sound of a helicopter. The DRS ‘Flatrol’ atomic flask wagon weighs more than 50 tonnes, and transports usually not more than 2.5 tonnes of spent nuclear fuel.
Scale model 1/144 (N scale).
DRS Nuclear Flask Train
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DRS Nuclear Flask Train – Paperdiorama.com