Pilatus Railway

The first project to build the line was proposed in 1873,[2] suggesting a 1,435 mm (4 ft 8 ¹⁄₂ in) standard gauge and 25% maximal gradient. It was concluded that the project was not economically viable. Eduard Locher, an engineer with great practical experience, then proposed an alternative project with the maximum grade increased to 48%, cutting the distance in half. Conventional systems at the time could not negotiate such gradients because the cogwheel that is pressed to the rack from above may, under higher gradients, jump out of engagement with the rack, eliminating the train's driving and braking power. Instead, Locher placed a horizontal double rack between the two rails with the rack teeth facing each side. This was engaged by two flanged cogwheels mounted on vertical shafts underneath the car.

This design eliminated the possibility of the cogwheels climbing out of the rack, and prevented the car from toppling over, even under severe crosswinds common in the area. The system was also capable of guiding the car without the need for flanges on the wheels. Indeed, the first cars on Pilatus had no flanges on running wheels, but they were later added to allow cars to be moved through tracks without rack rails during maintenance. The line was opened using steam traction on 4 June 1889, and was electrified on 15 May 1937, using an overhead electric supply of 1550 V DC.

The government provided no subsidy for the construction of the line. Instead, Locher established his own company "Locher Systems" to build the railway. The railway was built entirely with private capital and has remained financially viable throughout its life.

The Pilatus Railway was named a Historic Mechanical Engineering Landmark by the American Society of Mechanical Engineers in 2001.[3][4]

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  Share of the Pilatus Railway Company, issued 1. July 1888; founder's share
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  The train ready to leave, 4 June 1889
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  Pilatus Railway Time Table from 1905
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  A railcar at the summit station
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  Alpnachstad station; note the inclination of the platform behind the building
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  The Locher system rack and pinion
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  A turnout consisting of a bridge that rotates about its lengthwise axle
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  Pilatus Railway Rotary Switch
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  The two row transfer table in Pilatus Railway, one edge also serving as a passenger platform

The line is 4.6 km (2.86 mi) long, climbs a vertical distance of 1,629 m (5,344 ft), and is of 800 mm (2 ft 7 ¹⁄₂ in) gauge. Because of the rack-system, there are no conventional points or switches on the line, only rotary switches (see photograph) and traversers. All rails are laid on solid rock, securing rails by high-strength iron ties attached to the rock, without using any ballast.

The line still uses original rack rails that are now over 100 years old. While they have worn down, it was discovered that this can be fixed by simply turning the rails over, providing a new wearing surface that would be sufficient for the next century as well. The cars' electric motors are used as generators to brake the car during descent, but this electricity is not reused — it is just dissipated as heat through resistance grids. Originally, the steam engines were used as compressors to provide dynamic braking, since the use of friction brakes alone is not practical on such steep slopes.

The line is operated seasonally: May to October. The cable-car, which approaches from the other side, runs all year except for a short maintenance period.

• List of mountain railways in Switzerland
• Rail transport in Switzerland

• Book Tramways and Light Railways of Switzerland and Austria, ISBN 0-900433-96-5, by R.J.Buckley, published by the Light Rail Transit Association, 1984.

• Media related to Pilatusbahn at Wikimedia Commons
• Pilatus Railway web site
• Scientific American 8/13/1904; The Mount Pilatus Railway, Switzerland