The new M52 metro line in Amsterdam is 9.7km long, 7.1km of which runs underground. If a train breaks down, help is needed quickly. To this end, two Mercedes-Benz Unimog road-rail trucks are on standby ready to help. Working in tandem, these Unimog road-rail vehicles are powerful enough to pull even the heaviest 200-tonne metros out of the tunnel up the four-percent climb. 

This tandem operation has been possible since Amsterdam‘s GVB transport company received their second Unimog road-railer. Like the first vehicle delivered in 2017, the current truck is also a U 423 model capable of delivering 170kW (231hp) and 900Nm of torque. In order to apply the power to the rails effectively, the vehicles are equipped with a torque converter clutch. The rail guidance system necessary for rail transport and the control for tandem operation are from Zagro in Bad Rappenau. 

The new Unimog U 423 with a closed box body, a wagon brake system and hydraulic re-railing equipment is a flexible multi-purpose vehicle for GVB Amsterdam that is used for a huge variety of operative and maintenance tasks. The 2017 Unimog U 423, on the other hand, is equipped with a loading crane instead of a box body. It is used by GVB for renewing points, for example, or towing machinery. 

GVB, the Amsterdam municipal transport corporation, runs underground trains, trams, city buses and the city ferries. The company transports 227.1 million passengers per year, and with a staff numbering about 5000 it is one of Amsterdam’s major employers.