Diesel locomotive break down. Hydraulic transmission for locomotives was developed in Germany. There is still debate over the relative merits of hydraulic vs. electrical transmission systems: advantages claimed for hydraulic systems include lower weight, high reliability, and lower capital cost. By the 21st century, for diesel locomotive traction worldwide the majority of countries used diesel–electric designs, with diesel hydraulic designs not found in use outside Germany and Japan, and some neighbouring states, where it is used in designs for freight work. In Germany and Finland, diesel–hydraulic systems have achieved high reliability in operation. In the UK the diesel–hydraulic principle gained a poor
TU10 diesel locomotive used, although most of them have been replaced by TU7 diesel locomotives or TU7A diesel locomotives. The production of narrow gauge locomotives was discontinued in the 2000s because of the demise in narrow gauge railways in Russia, such as forest railways, peat railways and industrial railways, and this led to a lack of suitable new or second-hand locomotives for the children's railways. The Kambarka Engineering Works began in 2008 with the development of a modern diesel locomotive especially for use at children's railways. Based on the experience with older models, the following innovations were implemented: The locomotives have two equal