The VT 105 was a project for a lightweight articulated diesel train for intercity service jointly carried by the Bundesbahn, the German Sleeper and Dining Car Company (DSG) and the German Federal Post. It was designed by the office of Franz Kruckenberg and used many experiences in lightweight construction he had gained in the construction of the Rail Zeppelin and the SVT 137 155.
The trains featured a power car on each end and five trailers which were articulated on common bogies. The bodies were constructed of aluminium alloy. Each power car had two 118 kW MAN bus engines for propulsion which worked through a hydro-mechanical gearbox onto the leading two-axle bogie. Their power was later increased to 154 kW what increased top speed from 120 to 160 km/h. To provide head end power, each power car also had a 92 kW truck engine.
Of only two trainsets built, one was VT 10 501 that had been paid for by the Bundesbahn. It was used for the daytime “Senator” service and had five trailers which stood on one-axle bogies. The VT 10 551, paid for by the DSG, was intended for the nighttime “Komet”. It originally had five trailers which rested on two-axle Jacobs bogies. Later it was augmented by a sixth trailer.
After their first publicity tours in 1953, they were put into commercial service. Due to a multitude of failures, they often stood in the shop for repairs. 501 was retired in 1956 and 551 in 1958. A third mail train was only planned, but never built. In the end the maintenance was too expensive with six engines per train.
