The Chicamocha Cable Car. Image via flickr user Squiggle.
Often system length is used as an argument against Urban Gondolas and Cable Cars as a viable form of public transit. And while it’s true that most Cable Car systems are rather modest in length, that doesn’t mean they must be modest in length.
That’s why we once wrote about the Norsjö Aerial Ropeway in Sweden. If you’ll recall, that system was 13.2 kilometers long but was part of a converted mining system from the year 1943. Owing to its mineral extraction origins, the system is incredibly spartan and slow (10 km/hr).
To demonstrate system length we need something a little more – how shall we put it? – current.
Witness, then, the Chicamocha Cable Car near Bucaramanga, Colombia. The system dates from 2009, was built by Poma, uses current MDG technology, has three stations and is a whopping 6.3 kms long – arguably one of the longest systems in the world to use current MDG technology.
Granted the system is in no way, shape, form or description urban (it’s the centrepiece of Colombia’s new Chicamocha National Park), but it’s impressive statistics should demonstrate to anyone asking that current cable technologies can span lengths previously unimagined.
Take a look:
13 Comments
What would be a fundemental maximum length for gondolas? I would think the design variable you’d eventually hit would be the “mom, I have to pee” factor. At around 20 minutes for a one-way trip*, we might be approaching this limit. Of course, the solution might be to build bathrooms into intermediate stations.
Want to see a real long-distance (though purely conceptual) gondola line? Try this. Replacing two of Seattle’s ferries with gondolas. Ok, getting across 5km of open water might be tricky.
* I can’t see the video, so sorry if my speed assumption is wrong.
Longest gondola concept in the world?
http://www.eurasiangondolas.com/-/
I suspect the maximum distance is a function of the amount of propulsive force that is required to put the cabins and haul rope into motion. There is obviously a practical limit, and I suspect that it is well before 10 km. But I don’t know. An interesting question, Matt.
Since the example above is over 10km, I’d assume the limit is well over that. And that’s assuming only one drive motor – you could up the length either by adding another motor on the other end or by breaking the system into two ropes (or one set of ropes per 10km, onward).
Sorry. I wasn’t clear. One set of ropes probably limits you to much less than 10k in most applications. But when you transfer between ropes with multiple drives you certainly do expand capabilities.
From what I’ve been told, the challenge is not so much one of engineering, but rather transportation.
When round-up on a spool, steel cables can be quite large (and heavy) beasts – especially when you’re talking about lengths that are a dozen kilometers long. The challenge, then is how does one transport such a large (and heavy) piece of equipment. For all intents and purposes, your maximum length is going to be a function of the infrastructure used to transport the spool available in and around the project site.
Some data from the past – material ropeway from Massaua to Asmara – Erithrea Africa
75 kilometres length (road 125 miles) , 13 stations, 3 diramations and 9 changes of direction , 30 ton/hour per direction load capability… and it was built by the Italians in 1934 !
The 1/4 ton waggons had “pegs” to choose the destination of the load…
At the time, the use of ropeways and cable transport was truly competitive because much cheaper to build respect railroads, and trucks were too costly and not enough reliable and fast to be used.
Into the cities we are fast reaching the same situation even if road transport (bus , vans , trucks, cars) is easy and relatively cheap … simply we (anywhere in the world) can not afford a further increase in road traffic, and are facing constant rise in the road-connected costs -either for users , time lost in jam, fuel, parking, insurance- than collectivity , road maintenance, cost of traffic pollution, new parkings etc.
We are used to consider gondola as ski lifts, but this is an error, because what we see as current limitations (dimensions, number of stations, load capability etc) derives not from intrinsic tech limitations , but just sport/ski business exigences like the skiers load capability of a track
A double-line gondola (two for each directions) now could easily pass the 8000 pphpd in a 12 metres wide corridor with just a 45% cost increase respect a 3000 pphpd MGD…
a 2S or 3S could well have 3 km and more span, its just a question of dimensioning
We will see very soon big improvements in this sector.
Isn’t it fascinating how the urban market is so far behind the mining sector was 70 years ago? I find it incredibly funny.
Maximum length is 5-7 km, because friction losses become too big, to move the long rope.
You seem to be contradicted by at least three examples on this post. Modern ball bearings are much, much better than technology used in the 30’s, yet they pulled a gondola 75km back then.
Guenther (and myself) are coming at this from a practical perspective. You will probably never see a passenger ropeway span over 10km on a single rope. There are a lot of reasons for this (ie. Operational reliability, maintenance, power factors and drive sizes, etc.
It is far preferable to have multiple drives and ropes, and to have cabins switch between them, when we start dealing with long distances. The only exception to this might be systems designed for seasonal or tourist applications.
Couldn’t agree more. I think the reason it’s important to show systems like this, however, is to counter common public perception.
Most people would probably not be aware of how one uses multiple loops to create a single long line – its almost too complicated to explain within a culture obsessed with sound-bites and elevator-pitches.
Instead, it’s easier to just say “look, here’s a long line” and leave it at that.
But again, I agree with you fully.
Attention : the length of a line is not connected to the length of the rope, in the past the 2S system was the standard for material ropeways also because the sustain ropes (thicker and harder to made) could be splitted in several units (with tensioning built-in the pylons) when the traction rope was easier to make longer.
With actual technology, the single-span/single rope max distance for a MGD is about 3,5/4 kms – but it depends on the line profile (a sawtooth profile will must be shorter due for attrition)
2S and 3S could be much more longer and solve long span issues like rivers or straits
Anyway , since we are talking about urban lines, will be necessary to have stations at short distance – 600 to 900 mts – so it wont be a problem
What I intended is that is already feasible – and anyway cheaper than alternatives, a network of several gondola connected as diramations or intersections with the possibility to route single cabins to different destinations/lines as well as give the possibility to choose the destination in a cabin, like choosing the floor in an elevator… if it was not made is just because not necessary, but this could be a big plus respect a LRT or Metro line.