A cable car is a type of ground-level streetcar powered by a steel cable running continuously beneath the street surface. The cable travels through a slot or conduit below the roadway, visible through slots in the street between the two rails of the track. The vehicle is equipped with a device called a grip, a clamp operated by the driver to hold or release the cable. When the grip engages the cable, the car moves with it; when released, the car halts on the brake.

This system differs from the electric tram in that a separate motor is installed on the car itself. Here the motor is a fixed central one, housed in a power station where large pulleys turn the cable. Consequently the cable motion is constant and cannot be varied. The main advantage is that the car can climb very steep grades where ordinary tram wheels would slip.

History

This system saw major development in the nineteenth century, especially in hillside cities. Before electricity and internal combustion engines, the main transportation options for urban streets were horses or rail-based transit, both of which struggled on hills. The cable car proved a solution. San Francisco in the United States is the most famous example, where the system still operates in parts of the city. Other cities had such systems in Melbourne, Dunedin, Chicago and elsewhere, but most were replaced by electric trams and buses in the early twentieth century.

Components of the system

The system consists of a power station, a continuous steel cable loop, guide pulleys and cable supports, a slot beneath the street, and cars equipped with gripping apparatus. The operator manages two critical functions: engaging and releasing the cable, and braking. At stations, cables must be disengaged, requiring the operator to release the cable and coast through the station—a procedure called 'let go.'

Terminology

NoteThe English term 'cable car' can refer to two different things: (1) the ground-level cable-driven car described here, and (2) an aerial cable-suspended car (aerial tramway or gondola). It is also distinct from a funicular, which uses two counterbalanced cars on a single cable on steep grades. Somali terminology for these distinctions has not yet been fully standardized, making explanation necessary.

Today operating cable car systems serve primarily heritage and tourism functions rather than general transportation. Maintenance costs and declining ridership have made new systems economically unfeasible, although cable technology remains widely used in aerial transport and mountain funiculars.

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