Aerial tramway

An aerial tramway or gondola is a form of public transport, where vehicles are suspended on aerial cables. They are most commonly used in mountainous areas where traditional roads and rails are difficult to lay. It is sometimes called a 'cable car' but should be distinguished from a cable car on rails.

Aerial tramways may function in several different ways:

• Perhaps most commonly, a car is suspended from a heavy-duty cable and pulled by another non-load-bearing cable. (Compare funicular.)
• A car may be attached to a fixed point on a cable loop, which is then fed through motorized pulleys at each suspension point.
• A car may have a self-contained motor, which propels the wheels or pulleys by which the car is suspended from the cable.
• A car may have a motor which draws power from electricity carried in the cable itself.

The electric version was originally called telpherage, and was invented by engineer Fleeming Jenkin. Smaller telpherage systems are sometimes used to transport objects (such as tools or mail) within a building or factory.

Examples

• In Squaw Valley ski resort, California, USA, the 'cable car' (aerial tramway) system takes skiers from the base to the mountain top. The cars are attached to a fixed point on the suspended cable loop. When one car is at the top of the mountain, the other car is at the bottom. In other places, e.g. Heavenly Valley ski resort just few miles away, a similar system is called a tram.

• The Roosevelt Island Tramway, Manhattan, New York, USA, although also interesting for tourists, is claimed to be the only aerial tramway in North America directed mainly at commuters.

• Katoomba Scenic Skyway cable car, Australia

• The Telpherage system in the repair sheds of the New York City subway (http://www.nycsubway.org/irt/irtbook/ch11)