H-Bahn
Since 2011 Air Train International has been marketing the system in China and as of May 2013[update] there are proposals to build lines in Shanghai and Wenzhou.
The system can operate on a schedule or on-demand, whereby a passenger requests a carriage by pushing a button, similar to summoning an elevator.
The carrier is a hollow rectangular box girder with a slit in the bottom through which the cabin is suspended at the running gear, whose two axles carry the load with a rubber wheel on both sides providing both suspension and propulsion.
Each running gear is equipped with two motors, which are connected in parallel via their armature circuits (4-pole separately-excited DC machine with contraflexure poles).
Switching is done with the help of the horizontal guiding wheels, where short blades on both sides of the common section of the carrier move as a channel of the same width as the carrying box to the left or right, while a long blade between the two forking guideways moves right or left to provide the horizontal guidance into the intended direction.
A test line was opened on 21 July 1975 in Düsseldorf by the former transport minister Hans Matthoefer with a length of 180 metres (approx.
The first publicly funded overhead railway has run since 1984 at the University of Dortmund, where it initially just connected the north and south campuses with a single line.
The cost was approximately DM 24,000,000 (€12,270,000), of which 75% was funded by the German Federal Government, 20% by the state of North Rhine-Westphalia and 5% by the city of Dortmund.
The longest span between support pillars is 38.5 metres (126.3 ft), where it crosses the university road, which bisects the two campuses.
The existing system was renovated, and equipped with technology which allowed determining the train's location with a much higher precision — within 3 cm (1.2 in).
Further extensions to the H-Bahn network were being considered, but were not cost-effective enough: A nearly identical monorail system called SkyTrain transfers passengers at Düsseldorf Airport, which opened on 1 July 2002 after almost six years of construction.
