The Class 139 is unique on the British Railways system in being powered by a flywheel system. The flywheel stores energy. The flywheel is charged by a Ford diesel engine when the railcar is at rest, kinetic energy from the brakes and from downhill operation is also recycled [1].
WMR 139 001 at Stourbridge Town
London Midland at first, and currently West Midlands Railway operates the railcar along the short Stourbridge branch between Stourbridge Junction and Stourbridge Town[2]. Two Class 139s have been built. There was also a prototype built in 2002 which was used to prove the flywheel concept. It ran on a number of heritage lines for testing and was referred to as the Class 999.
Information
Number built:
2
Built:
2007-08
Builder:
Parry People Movers
Motor:
Ford DSG423 diesel driving flywheel
Power:
86 hp (64 kW)
Formation:
Driving Motor Second (DMS)
The Class 139 is a small railcar (less than nine metres long) though has seating capacity for over twenty people plus over thirty standing.
The Class 139 began operation on the Stourbridge branch in 2009 releasing a Class 153 for other duties. The Class 139s are not allowed on any other part of the network and have their own little "depot" at Stourbridge Junction [3].
