Overview
An aerial tramway consists of one or two fixed cables (called track cables), one loop of cable (called a haulage rope), and two passenger cabins. The fixed cables provide support for the cabins while the haulage rope, by means of a grip, is solidly connected to the truck (the wheel set that rolls on the track cables). An electric motor drives the haulage rope which provides propulsion. Aerial tramways are constructed as reversible systems; vehicles shuttling back and forth between two end terminals and propelled by a cable loop which stops and reverses direction when the cabins arrive at the end stations. Aerial tramways differ from gondola lifts in that gondola lifts are considered continuous systems (cabins attached onto a circulating haul rope that moves continuously).
Two-car tramways use a jig-back system: A large electric motor is located at the bottom of the tramway so that it effectively pulls one cabin down, using that cabin's weight to help pull the other cabin up. A similar system of cables is used in a funicular railway. The two passenger cabins, which carry from 4 to over 150 people, are situated at opposite ends of the loops of cable. Thus, while one is coming up, the other is going down the mountain, and they pass each other midway on the cable span.
Some aerial trams have only one cabin, which lends itself better for systems with small elevation changes along the cable run.
Read more about this topic: Aerial Tramways