The Multiple-purpose Vehicle or MPV is a purpose-built departmental derivative of a diesel multiple unit. Twenty-five two-car units were ordered by Railtrack to enable it to replace its varied collection of ageing departmental vehicles, many of which were converted from redundant passenger stock.
The vehicles were built in Germany by Windhoff. The design is based on the Windhoff "CargoSprinter" units that are operated by Deutsche Bahn (Germany) and CRT Group (Australia). Normally a unit consists of one powered vehicle fitted with twin 265 kW (355 hp) Railpac diesel engines,[1] semi-permanently coupled to an unpowered slave unit without engines (effectively a driving van trailer). The later orders for the South East of England and for overhead line replacement are instead composed of two powered units, to give better acceleration and top speed.[1] When first built there were problems with the vehicles being 'out of gauge' when running empty.[citation needed]
The concept of the design is that each vehicle has a driving cab and an under floor engine/transmission with Multiple unit (MU) control. The majority of each vehicle is a flat load bed that can carry combinations of 10-foot and 20-foot modules that are secured using the locking system for ISO standard containers. Modules can be changed as required to suit current requirements.
