The aerial tram is one of the original aerial cable transit types. Generally aerial trams are two-vehicle, two-station systems with non-detachable grips.
While they are limited in their capabilities, what they can do, they do well. Essentially aerial trams can reach high speeds and are therefore really good at moving people between two points over shorter distances. (At longer distances the two cabins become less efficient.)
Because vehicles are attached to their haul rope (propulsion cable) with non-detachable grips, as the two opposing cabins enter the stations, the entire system is brought to a full stand still. The two cabins shuffle back and forth between the two stations, hence why aerial trams are also known as reversible tramways. This also make turning and mid-stations mear impossible.
Grip: Unlike a gondola (MDG, BDG, 3S) an aerial tram utilizes non-detachable grips. This means cabins cannot detach from the cable, which makes turning near impossible and intermediary stations rare.
Speed: Systems can operate as fast as 12 m/s, which is equal to 43 km/h.
Capacity: Cabins can be small or large, holding as few as 6 or as many as 200 riders at one time. Yet, because there are only two cabins per system, this amounts to no more than 2,000 people per hour per direction.
Towers: Styles vary greatly. One of the most visually striking and iconic towers is part of the Portland Aerial Tram.
Cost: Although cost is very dependent on location, situation, and customization, generally the cost for an aerial tram is generally between $10-30 million (US) / km.
Note: Cost estimates given are for informational purposes only. Actual costs can vary dramatically for individual systems.
The original Roosevelt Island Tram in New York City was an aerial tram. Constructed in 1976, the system operated for over 40 years before it was overhauled in 2010 as a dual haul aerial tram — a configuration that the same as a standard aerial tram in all ways except that the two vehicles operate on independent loops. Rather than being attached at opposite ends, one car can be closed for maintenance or during times of low ridership, while the other vehicle continues to operate. For this reason, dual haul aerial trams can operate around the clock.
Note: Systems are rarely, but can be built with only one vehicle. Also rare but technically possible, aerial trams can have more than two stations. Because the system must stop fully at each station this would be most viable if the mid station was exactly between the two end stations so vehicles only came to a complete stop in a station.
The Gondola Project has profiles on several aerial tram systems, including:
If you’re looking for the original post on aerial tram technology, you can find it here.