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Is there any good reasoning why some lifts spin clockwise and some spin counter clockwise?

I've noticed some areas almost or all of their lifts spin one direction, such as killington almost all of their lifts spin counter clockwise, then bradford (if any of you have even heard of it) all their lifts spin clockwise.

I really cant think of much of a reason why, unless it's 90 degree loading and the line would be directed toward one side.

shade for the load / unload ramp. would be one reason. (i'm guessing)

Can the grips only operate in one direction?
(say, if you wanted to use a replacement grip from another lift on a lift that went in the opposite direction, would it still work well? It looks like the new DoppelmayrCTEC grips have the tyre plate sloped down more on one end than the other, and the needles curve upward on the trailing edge but not the leading end) I think you can, but that was interesting to see the CTEC grips obviously geared towards one direction. Here's a crude drawing to explain what I'm saying  ctec_diagram.jpg (21.57K)
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Also, are the towers stronger on the heavy side or anything, or does it not matter?
(Reason for that question is that DV might want to do 90 degree loading for Sultan this summer, but it turns the opposite direction. They're probably reusing the towers, but after 24 seasons with the heavy side on the left, would it be a problem to switch it to the right? (or maybe a benefit?) Again, I don't think it would be a problem, but I don't know much)

This might be a good question - if they want to install a line turn (i.e. the ones on Baldy at Snowbird, Silver Strike at DV and The Canyons Cabriolet) does the heavy side have to be on the outside of the turn?
(another thing that might require Sultan at DV to rotate the other direction)

Loading and unloading are really the only reasons to have a lift rotate one direction over the other. Tower loads can be adjusted and there is no one side stronger than the other. Grip needles curve upwards because of rope sag and depression sheaves (and when we rebuild them we put the least curved one in the front to avoid possibly catching on depression sheaves). Traction plates are either bi-directional or can be reversed. The turns mid-line you're describing can be made regardless of lift rotation. Shade has nothing to do with rotation. I think I've addressed all of your points, Tyler and Jeff.
As far as loading, yes, 90-degree loading does determine the direction of the lift because of where the maze needs to be. Unloading affects rotation because if you can, it's better to have the carriers swing around the bullwheel away from most of the skiers. This means that if most people unload to the right, you want the lift to swing to the left or counterclockwise.

Yeah, it would depend on which side it would be easier to load from, factoring in traffic and terrain.

Loading and unloading are really the only reasons to have a lift rotate one direction over the other. Tower loads can be adjusted and there is no one side stronger than the other.

Also if the lift is traversing a side hill the "ski under" effect and clearance issues will effect rotation.

How does a ski resort decide whether a chairlift should run with clockwise rotation or counterclockwise location? I assume part of it has to be location.

Funny enough, the random questions thread had me thinking of asking the same question! All other things being equal, is there a preference?

I believe it has to do with how the location and how the queue is set up.

Though I have seen some lifts where both clockwise and counterclockwise would work, although they chose a certain rotation for whatever reason. The Kensho SuperChair is one example. I think the Keystone high speed quads are all this 'they could have set them up either way and the queue would be the same'. With Vail, the only ones that are forced to a certain rotation because of location would be the Skyline Express, Teacup Express, Mountaintop Express and Highline Express, due to their bottom terminals.

If either works I'm assuming the resort has a preferred direction, so they can keep maintenance more simple. Snowbird is a good example of this. MBX and Gad 2 could have worked either way, but almost all of the lifts at Snowbird go clockwise so those go clockwise too.
This post has been edited by SkiDaBird: 26 April 2014 - 11:54 AM

Killington sets all their queues up so that they have to be counterclockwise or that either way would work, and then they just install the lift counterclockwise anyway. They do not have a single clockwise lift in their entire history.

snoloco, on 26 April 2014 - 01:04 PM, said:

Some lifts have to go a certain direction due to 90 loads and unloads or midstations. 5 of the 8 HSQs in LCC have to go in the direction they do.

90 degree loads/unloads only ever get utilized if there is a space issue at that terminal. The Lower Beaver Creek Mountain Express lift, for instance, uses a 90 degree unload because the terminal is wedged between the Bachelor Gulch Express lift and the bottom terminal of the Upper Beaver Creek Mountain Express lift. Therefore it has to run clockwise. The Imperial Express SuperChair has to use a 90 degree unloading and clockwise rotation due to limited space at that point on the Peak 8 ridge.

As for Snowbird, they have 90 degree unloading on the Baldy Express, Little Cloud Express and Peruvian Express. They also have 90 degree loading on the Mineral Basin Express. Alta has 90 degree loading on the Sugarloaf Express.

Snowbird has 90 degree unloading on Baldy and Little Cloud because of limited space on the ridges and Peruvian has 90 degree unloading because it ends directly in the mountain.

DonaldMReif, on 26 April 2014 - 02:48 PM, said:

MBX does not have 90 degree...
You are thinking of Peruvian
This post has been edited by SkiDaBird: 27 April 2014 - 08:36 AM

Not terribly relevant, but I have always wondered why every aircraft carrier ever built (I think) has been "right hand drive". (i.e. the control tower is on the right hand side of the ship.)

Now it makes sense for countries like Britain, Japan and Australia that have that have cars with steering wheels on the right to apply the same concept to their aircraft carriers. But I would have thought that countries like the United States and Spain that have their car's steering wheels on the left would have aircraft carriers with the island on the left too.
This post has been edited by Bogong: 12 May 2014 - 05:03 AM

There are several theories regarding the positioning of the island on an aircraft carrier. Among the most pertinent: propeller rotation (torque) gave aircraft a little sway to the left (as most single engine aircraft propller rotates clockwise). Aircraft also turn left when missing a landing, by convention. Once they've build it like this, they've got to keep to this design as to not confuse the pilots.

But, there were at least two aircraft carriers that sported a port side island: the Japanese Akagi and Hiryu (WWII). Didn't helped too much.

All of Stratton's lifts are counterclockwise except for Tamarack. It is their oldest lift and was installed before the mountain was counterclockwise dominated. I think that when they installed their gondola, fixed grip quads, and 6-packs, they decided to make them all counterclockwise to make maintenance easier. Tamarack would work with both rotations, but it was installed when there were both clockwise and counterclockwise lifts on the mountain in more equal numbers.
This post has been edited by snoloco: 11 May 2014 - 12:02 PM

From a mechanic's perspective it makes no difference which direction the lift rotates. It's almost always loading and unloading configuration that matters.