Sugarloaf Double Double. Image via Livejournal.
Yesterday I asked readers to check out this link that led to a picture of a double-double chair lift at Sugarloaf resort in Maine. I asked readers to discuss why such a system is important to the world of Cable Propelled Transit and Urban Gondolas.
As the system in question had recently been involved in an accident, I’m sure many thought that was what I was looking for. Admittedly, that was a bit of a red herring, and not what I thought to be most important. Of all the answers, I think Chip’s came closest, but really didn’t get to the heart of what I was after.
Here’s my interpretation:
Within the comments of a previous post, I discussed the idea of being able to theoretically double capacity of a gondola line by using the same tower infrastructure to carry two separate loops. (I also suggested tripling a line could be possible. I suspect, however, that was overzealous and wishful thinking on my part, but I digress).
Some rightly suggested that because such a thing had never been attempted before, it might arouse suspicions and worries.
And yet here in Sugarloaf we have a system from the 1970’s that demonstrates that the concept is not so outlandish. It suggests that there is actually an historical precedent for such an idea.
Now of course a double-seater chairlift is a different beast than a gondola system. Nevertheless, it doesn’t take much of a mental leap to move from two loops of chairlifts on the same tower to two loops of gondolas on the same tower. The concept is equivalent in spirit if not exactly in execution.
Yes, there is the question of the double-double’s aesthetic. The aesthetics of CPT are already questionable. Building something like this would likely restrict even further the kinds of environments where an urban gondola transit system could be successfully implemented.
Nevertheless, finding a real-world example of how twinning/stacking two loops on the same tower infrastructure can – in essence – double the capacity of a gondola transit line is important. Suddenly an MDG’s upper limit isn’t 4,000 pphpd, it’s 8,000.
Beyond that, the reason I brought attention to this image is much the same reason I brought attention to the slim-profile high-speed angle station found at Grindelwald First. Both systems have a unique curiosity that hold potentially major implications for Cable Propelled Transit systems. And like the Grindelwald First system, I “discovered” it purely by chance – were it not for the recent accident at Sugarloaf attracting my attention to the system, I was unlikely to ever stumble across such a system.
We shouldn’t be finding these things out by accident.
Combined, the two major manufacturers of ropeways have built over 20,000 systems around the world. That’s a lot. Meanwhile, many of those systems were built by subsidiaries and lesser companies that were scooped up in the mergers and acquisitions craze the industry went through in the late 1990’s.
How then does one keep track of and catalogue each system? How many other curiosities exist out there that no one – not even the industry itself – knows about?
Better yet: How many other curiosities exist out there that hold no interest to the cable industry whatsoever yet have mass implications for the urban market?
The last thing anyone wants to do is go step-by-step through every single one of the 20,000 plus systems that have ever been built, but I suspect that may be the only way to find out.
Time to get cracking!
And to all the Canadian readers out there: Does anybody but me find it hilarious to call it a double-double?
8 Comments
Forget a double double, let’s strive for a triple triple
Creating a database of CPT systems sounds like a fun project to me. I wish I had the time to do it.
So the point of double cable would be to have half the spacing between cars without needing to increase the amount of towers? Would load times between the cars still be decent? You also mention skipping stations but how much time is saved when the cars are still stuck behind one another, an animation showing how multiple lines work would be helpful.
@ Seth,
I think the point would be to effectively double capacity. There’s also the potential for trunk lines as Chip alluded to earlier.
I didn’t follow the discussion on the Toronto post (having never been there), or I’d probably have provided a similar link. If capacity is the only issue, it’s a lot simpler to design for higher-capacity carriers; this is why quads are pretty much the standard these days and double-doubles aren’t being built anymore. The situation where shared towers makes sense is if you’re building a system where two lines start from the same point and diverge at a subsequent station.
The spacing would be the same as on a conventional ropeway of the same type; these are two independent systems that share a set of towers.
Note that Sugarloaf has two of these; the one in the image in this post is Spillway, where the accident happened. The previous day’s image was of Double Runner, which is visible in today’s picture running up from the base area; the longer side’s upper terminal is just to the left. (Sometime in the last couple years, Sugarloaf painted their lift towers white; this picture is from before then.)
There are a couple of lift-database sites, none of them particularly complete. The ones I’m familiar with are skilifts.org and lift-world.info.
@ Chip,
I was actually referencing your comment from the “Do You See What I See?” post.
I”m really interested in what you just said about diverging lines. Does such a thing exist? Where. I know skilifts.org and lift-world.info, but a lot of the database is lacking info and doesn’t provide visualization.
What I meant was that I missed the discussion on parallel lines, or I’d have mentioned the shared-tower configuration then; it’s also why I didn’t entirely get the “do you see what I see” post.
I don’t know of an example of shared-tower lifts diverging onto different alignments; the only such installation I’ve seen that wasn’t a fixed-grip chairlift was a pair of 4-passenger MDGs at the La Ronde amusement park in Montreal, built for Expo ’67 and long since dismantled. But there’s no technical reason why it wouldn’t work.
FYI: http://www.flickr.com/photos/vonroll/2685354621/#/photos/vonroll/2685354621/lightbox/