Turning Lifts with Sheaves Instead of Stations

We’re used to lifts that run in a perfectly straight line between terminals but sometimes a lift just has to have a turn.  Common reasons for this uncommon occurrence include buildings in the preferred alignment and challenging property lines.  Most lifts with turns are detachable systems with angle stations which are very expensive.  But not all lifts that need to turn require loading or unloading mid-way.  In a handful of these cases, lift manufacturers have avoided the need for angle stations or extra bullwheels by designing towers with canted sheaves.

Look closely at the very top of Six Shooter at Big Sky. The last few towers are in a different alignment than the rest of the lift.

The first company to use this trick was Riblet with Chair 5 at Breckenridge way back in 1970 1986. Closely-spaced towers 10A, 10B and 11 have angled sheaves in a compression-support-compression setup.  I’m not sure of the exact angle of the turn on Chair 5 but its a couple of degrees.  (Edited to add later: the lower terminal and towers of Chair 5 were moved in 1986, 16 years after the lift was first built.)

If you look closely, the Baldy Express at Snowbird does not run in a straight line. Don't worry, this was by design and it's been done a number of times.
The Baldy Express at Snowbird also does not run in a straight line.  It’s by design!

Most of the lifts that turn using angled sheaves were built by Doppelmayr CTEC and its predecessor Garaventa CTEC and turn less than five degrees.  A turn is typically accomplished over three towers with the middle of the three being a depression assembly.  The Cabriolet at Park City (formerly Canyons) was the first modern lift with this setup and opened in 2000, connecting the main parking lot to village.  Its five degree turn was required due to private property lines and existing buildings.

Canted sheaved on the Cabriolet at Park City, a 2000 Garaventa CTEC Stealth detachable.
Canted sheaves on the Cabriolet at Park City, a 2000 Garaventa CTEC Stealth detachable.

A year after the experiment at The Canyons, Garaventa CTEC built another detachable with a turn for Snowbird.  The Baldy Express turns between towers 10 and 12 again due to private property lines.  The first six pack with a turn was the Six Shooter at Big Sky (formerly Moonlight Basin) which was built in 2003 and has a couple degree turn between towers 24 and 26.  I’ve heard Six Shooter’s turn was due to a surveying mistake that would have put the top terminal on Big Sky Resort’s property.  Doppelmayr CTEC engineered the turn rather than re-doing a bunch of tower bases.  The irony here is that ten years later Big Sky ended up buying the land and lifts anyways.

Six Shooter at Big Sky is a very long six pack with a turn about two thirds of the way up.
Six Shooter at Big Sky is a very long six pack with a turn about two thirds of the way up.

The 2004 Silver Strike Express at Deer Valley is the most recent lift built with a mid-line turn; it deflects 2.5 degrees from towers 5 to 7.  Silver Strike was the fourth detachable quad built to the top of Flagstaff Mountain with a very tight squeeze between the existing Northside and Quincy lifts.  The lower part of the line threads through multiple condos and hotels.  With constraints on either end, the only solution was to turn the line in between.

The most recent lift built with the angled sheave scheme is the Silver Strike Express at Deer Valley.
The most recent lift built with the angled sheave scheme is the Silver Strike Express at Deer Valley.

Of course, not all turns can be accomplished without angle stations and bullwheels.  Right next to the Cabriolet at the Canyons is the Red Pine Gondola, which makes a turn way too sharp to be accomplished with angled sheaves.  In this case, Leitner-Poma designed an angle station where cabins detach and reattach without the doors opening.  No doubt this was very expensive but the only solution for such a significant turn.

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5 thoughts on “Turning Lifts with Sheaves Instead of Stations

  1. Donald Reif August 14, 2015 / 12:29 pm

    The reason for Lift 5’s turn is because the bottom terminal was shifted about 100 or so feet south in 1986 when the first Colorado SuperChair was built.

    Like

    • Peter Landsman August 14, 2015 / 11:05 pm

      I’d forgotten that, thanks Donald. I will update my post.

      Like

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