A new concept is to use the multiple unit idea for freight traffic, such as carrying containers or for trains used for maintenance. The Japanese M250 series train has four front and end carriages that are EMUs, and has been operating since March 2004. The German CargoSprinter have been used in three countries since 2003.
Steam
The United Kingdom had various examples of Autotrain on branch lines, whereby a steam locomotive could be controlled by driving trailers at the opposite end of the train, or in the middle. This avoided the need to run around the locomotive at the terminals. These autotrains were limited to about two carriages, however the Great Western Railway's Autotrain system allowed a locomotive to be placed in the middle of a four coach train and controlled from the cab of either of the two outside carriages (Autocoaches). The CargoSprinter is a multiple unit (or articulated) freight car; it could also be thought of as a container truck that runs on rails. Built by the German company Windhoff, it is in effect a self-propelled flatcar for containers. It is intended to recapture some of the freight market back from road trucks, by making it economically feasible to carry small amounts of freight to the individual sidings of warehouses and businesses, without the complications and overhead of conventional locomotive-hauled trains. The unit consists of two driving and power units, each fitted with a full width cab and two Volvo truck engines for propulsion, which operate in a push pull mode, with up to seven trailers in between. The drive train is hydraulic via an automatic 5-speed gearbox, and has a maximum speed of 120 km/h. The complete train has a total power output of 4 x 265 - 1060 kilowatts and weighs 118 tons.
