23
Mar

2011

Cable Cars, Lesson 2: Single Loop Cable Shuttles

Post by Steven Dale

Mexico City Airport's Aerotén. Image via Sobre Mexico.

For our new readers: Despite the fact that systems like the planned London Thames Cable Car are often officially called “Cable Cars,” they are more often than not Gondolas. This can be confusing to cable transit novices. To make it easier: Cable Cars are supported from below (like cars) and Gondolas are supported from the top (like ski lift gondolas). This is an error of nomenclature, nothing more.

As I described a long time ago here, Cable Cars operate in a similar way to Gondolas. That is, they come in either continuously-circulating or shuttle-based configurations. For all intents and purposes, you can imagine shuttle configurations as being the ground-based equivalent to an Aerial Tram – the only difference being that Cable Cars can navigate turns easily whereas Aerial Trams cannot.

As such, shuttle based systems are – generally speaking – the simplest and cheapest Cable Cars to install. They suffer, however, from having relatively low system capacities (as measured in pphpd).

Like an Aerial Tram, a basic Cable Shuttle has only one rope loop. That means there can only be a maximum of two vehicles plying the line in question. Those two vehicles are also bound by each other. They operate in tandem; one vehicle cannot move without the other.

So while there may be a variety of different ways to apply a Single Loop Cable Shuttle (see image below), the system will always be characterized by low capacities; an inability to offer 24 hour service; longer wait times and; severe restrictions on intermediary stations.

In the event of a single track, single vehicle configuration, intermediary stations can be placed at whatever interval is desired.

Like all transit systems, the exact capacity of a Single Loop Cable Shuttle is a product of many factors. System speed, dwell times, number of stations, vehicle size and system length all factor into the equation and it is therefore impossible to provide any reliable benchmark for what such a system can carry. Each system would be unique unto itself.

Nevertheless remember: A single loop system is at the low-end of the Cable Car spectrum and it’s capabilities are limited in comparison to other Cable Car technologies. For example, Mexico City’s Aerotrén is a single loop, single track system with only one vehicle. Though it travels at a maximum speed of 45 km/hr, it currently only provides a system capacity of 540 pphpd.

Like an Aerial Tram, a Single Loop Cable Shuttle is therefore only appropriate in low-capacity situations where complexity is at a minimum.

Image by CUP Projects.



Want more? Purchase Cable Car Confidential: The Essential Guide to Cable Cars, Urban Gondolas & Cable Propelled Transit and start learning about the world's fastest growing transportation technologies.

Want more? Purchase Cable Car Confidential: The Essential Guide to Cable Cars, Urban Gondolas & Cable Propelled Transit and start learning about the world's fastest growing transportation technologies.

Comments

  1. I presume other lessons will follow describing the other vehicle/guideway/rope loop/station location options that exist and that allow for higher capacities... More can be found here in this very Doppelmayr (DCC) -centric wiki page. http://en.wikipedia.org/wiki/Cable_Liner
  2. @ BC, Regarding other Cable Car techs: We'll definitely be rolling out more primers on the other Cable Car systems. Problem is, like the aerial technologies there's at least half-a-dozen, and it takes more time than I have.
  3. To increase confusion: Sometimes you find a Single Cable Liner Shuttle with a cable drum, winding the cable (without a loop). Or you find a Single Cable Liner Shuttle with a counterweight on a carriage rolling on rails (inclined elevator).
  4. @ Guenther, I'm not so much worried about those issues. Those are very specific matters that really on the engineers need to know about. But for the decision-makers, researchers and planners who actually approve these systems as public transit it is imperative that they know the difference between an Aerial Tram and a Gondola and a Cable Car. We've seen too many times where reports have been written that confuse the technologies.
  5. A problem is, not all manufacturers use the same translations: Tricable Gondola Detachable or Tricable Ropeway Detachable ? Another complicated definition means you have two tension ropes and one traction rope, but there are only two different rope types, so it is a Twocable Ropeway (Arthur Doppelmayr) or a Bicable.... Very confusing. For example, a data transfer cable is another different cable. If it is fixed at the gondola, only now you have a TRIcable... And is a "haule-rope" a "carrying-hauling rope" or a "haule-cable"? Or is a "tower" a "support" ? §;o( Crazy ! We must find in a library the "Legal Glossary of ropeways" available in German, French, Italian, English, Slovenian, Spanish and Catalan. published by the O.I.T.A.F.; http://www.oitaf.org booklet nr. 19;
  6. I'm excited to see you getting back to the technology primers. Lessons on cable cars have been conspicuous in their absence for a while and I look forward to seeing more.
  7. Thanks Erik! It's difficult balancing the tech-primer needs while also balancing link bait and philosophical needs as well. Thanks for sticking with us though. If ever you get frustrated about a lack of something (or too much of something else) feel free to send us an email!
  8. @Gunther, regarding "“Legal Glossary of ropeways". I went to OITAF website and politely asked for this document referencing this website. They sent me a copy. It is more a translation guide than a glossary and simply lists the translation across languages. So for Gondola lift, it has: Kabinenumlaufbahn, Télécabine, Cabinovia a moto continuo, telecabina, Krožna kabinska žičnica, Telecabina, Telecabina It also has this disclaimer: The glossary is meant as a simple survey of legal terms most frequently used, a glossary that does not claim to be comprehensive nor correct in as far translations are concerned. Due consideration ought to be given to the fact that national legal systems differ one from another and legal concepts used may therefore have a differing meaning or are likely to receive a differing interpretation. Authors decline any responsibility related to the use of the glossary. If there is a specific term you want me to look up & post, I can do so but I don't think this document is going to solve our nomenclature problems.
  9. The OITAF folks recommended the following standard for terminology: DIN EN 1907 "Safety requirements for cableway installations designed to carry perons - Terminology" German version EN 1907:2005. See: http://www.techstreet.com/standards/DIN_EN/1907?product_id=1251651 They don't own that doc so they can't give it to us.