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Crevasse rescue pulleys
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By kparry
Sep 20, 2013
We've been practicing setting anchors and pulleys and general crevasse rescue techniques for an upcoming trip on Alaska. As we problem solve each new situation we got to thinking about a block pulley system (like is used for a main sail on a small sailboat). It's small, relatively light and can be set up on a single anchor location. Can this be used as an alternative to setting up a "Z", or double z, system to haul out big loads/people? Pros? Cons? Thanks for your input

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By wfscot
From Boulder, CO
Sep 20, 2013
In theory, yes, but how would you reset it once you have collapsed the pulleys?

The advantage of the Z-pulley system is that it's very easy to reset once it has been collapsed. In most real-world rescue situations, you will need to do this at least once.

Along these lines, I did a bunch of testing with my team prior to Denali last year and was amazed at how much easier it was to haul using a Z with a traction device (Petzl Micro Traction in our case) vs auto-minding pulley and prusik. The difference is the ability to rest between pulls. Even with a optimum length (i.e. as short as possible) prusik, you have to give up quite a bit to get it to bite, making resting in between pulls much more difficult. I would estimate it was something like 50% easier.

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By Eric and Lucie
From Boulder, CO
Sep 20, 2013
There is already a pulley system like that made specifically for climbing by Mammut: mammut.ch/en/productDetail/221...

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By Mark Pilate
Sep 20, 2013
wfscot - They would re-set their system the same as re-setting a "Z", no matter the advantage system you create, you still need a lock-off point (personally, I just use a reverso-4 in guide mode) and a Tibloc/prussik to set/re-set the pull rope.

But as pointed out, Mammut has exactly what the OP is looking for in a lighter weight package.

Personally don't think its needed, but to each his own system

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By hikingdrew
From Los Angeles, CA
Sep 20, 2013
dorky helmet
One issue with purpose made crevasse kits is that all the gear is in one place, so if the guy carrying it falls in, well... When we trained up there we had each member carry 2 pickets, a pulley or two and a couple prussiks and biners. That way, you could construct 2:1, 3:1, 6:1 regardless of who fell in.

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By Mark Pilate
Sep 20, 2013
the simplest way is to just grab the rope and yard 'em out hand over hand...'course you need a set of pipes like mine and they don't come easy.

For y'all I recommend you festoon your harness with traxions, tiblocs, prussiks, slings, pickets, and other rescue accoutrement...and clank your way across the glacier in teams of 5.

Or tie overhands in a long rope to max the friction and limit the drop -- anyone ever do this?

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By hikingdrew
From Los Angeles, CA
Sep 20, 2013
dorky helmet
We tied overhands on bights for 2 person rope teams...

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By wfscot
From Boulder, CO
Sep 20, 2013
Mark Pilate wrote:
Or tie overhands in a long rope to max the friction and limit the drop -- anyone ever do this?


I could easily be mistaken, but my understanding is that this is pretty much the standard in Europe. Extra rope is then carried to do a simple dropped-loop haul after the (shorter) fall. Honestly, I'm pretty sure that haul would be easier than a Z using the incident line (shorter 2:1 where the edge can be optimized vs a longer 3:1 with an entrenched edge).

But if you still need a capture device in addition to the block pulley, then why are we having this discussion? I challenge you to get lighter and simpler than a Z using 1 micro traction + 1 pulley and prusik (or tibloc).

And if you've got 5, brute force away. If you're <= 3, though (which is way more fun), brute force over an entrenched edge just ain't an option.

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