Knot question

5:18 p.m. on February 28, 2014 (EST)
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This is sort of a follow up to my z-pully question last time. Anyone with knowledge of knots can feel free to help.

I will try to attach a link to a video I took of this knot. It is possibly an alternative knot to a butterfly knot when tying in to a rope team.

I don't recognize the knot so I didn't know if we made one up or if anyone else recognized it.

If we did make it up do people think at first glance that it looks safe? We will obviously test it as well.

6:09 p.m. on February 28, 2014 (EST)
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Watch "Knot question for rope team" on YouTube https://www.youtube.com/watch?v=H6ynm01eMbA&feature=youtube_gdata_player

5:27 p.m. on March 1, 2014 (EST)
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Check out this website about tying knots.

http://www.animatedknots.com/

10:00 p.m. on March 1, 2014 (EST)
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What are you wanting to do with this knot (actually, it is a hitch)?

It is a variation on the girth hitch, as you allude to in the video. There is an easier way to tie the hitch, that is less prone to error. It is fairly easy to make an error that leaves you detached from the rope at a critical moment, so I suggest you not rely on this hitch. From your earlier questions relating to crevasse rescue, I am guessing that you are still seeking a solution to the problem you encountered with the prussik jamming against your tie-in butterfly when you are setting the first anchor after a crevasse fall.

I would strongly suggest you get a copy of Andy Selters "Glacier Travel & Crevasse Rescue" (Mountaineers Press). Read it several times through to understand it thoroughly. Then hire a guide (IFMGA or  least AMGA certified in glacier travel) for a thorough 1-on-1 session. Keep in mind that you are learning life-critical skills. There are a couple of other good books with clear discussions of crevasse rescue.

A big advantage to using a known and vetted source like Selters plus 1-on-1 instruction from a certified guide is that you will be using the same procedures as people from other parts of the country and even other parts of the world. Things work better when everyone involved is on the same page. It is bad enough when people use their own versions of commands (e.g., on a sport climb, you often hear "Got me?", "Take!", "Done!, Lower!" all for the same thing, and even worse on a busy sport area or gym when you don't know over the cacaphony whether that is "Joe" or "Sam" or "Mary" calling "Off Belay")

Last summer in Peru, we had 2 guys who were supposed to help with getting some of the grad students up the mountain to collect samples who disagreed with our designated safety director on how to handle a crevasse rescue. Those of us who had been on glaciers for years were of one accord, in agreement with our designated safety director, with the 2 being very adamant. They ended up getting booted from the expedition.

10:15 p.m. on March 3, 2014 (EST)
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Thanks bill for the response. I actually have taken a detailed 1 on 1 glacier travel/ crevasse rescue course from a certified guide...it's why I know enough about it to explore more options and see what works best.

Obviously if this knot doesn't work well in practice than we will stick to tried and true methods that are proven to work. I just enjoy exploring the options and seeing what else is out there.

I think we've managed to clean up the knot jamming issue by using a tibloc for the foot loops instead of the prussick. The issue still seems that the butterfly knot that leads to the fallen climber takes the load of weight and while loaded is a massive pain to untie so that the rope can feed through the pulley system.

Again, if need be, even though it's a pain, at least we know that the tried and true method works.

I wonder if this hitch would be very difficult to take off the carabiner once it takes a load since it self brakes? My guess is that it would muckle on to your locker like no other and taking yourself out of the system following the anchor placement would be nearly impossible as long as the rope remains loaded.

Thoughts?

8:33 p.m. on March 4, 2014 (EST)
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iClimb,

I am still puzzled here. If you have the rope set up right, with 1 butterfly for each climber to clip into with a clocking carabiner and the prussick on the side of the butterfly toward the other climber, then while holding the fall (in self-arrest position), you place the first anchor and slide the prussick away from the anchoring climber (toward the victim), the weight should be fully on the prussick and clear of the butterfly. Similarly, if the victim is going to prussick out of the slot, s/he will slide the waist-loop prussick up the rope away from the victim's butterfly knot (up toward the belayer), then step into the leg loops and start alternately shifting the waist and leg prussicks up the rope.  The important point here is that the prussick knots for both victim and belayer are between the two of them, hence between the butterflies.

I am assuming you are using the usual 3 prussick version of the Texas Kick setup - leg loop, waist loop, and pack loop.

For the C- or C-Z extraction (I am taking the 2-person rope, since that is what it sounds like you are contemplating - 3-person is much easier), the belayer's foot-loop prussick is used to anchor to two points (either flukes or pickets, preferably deadmanned) beyond the belayer, who then slides the knot away from him/herself toward the victim while still supporting the weight of the victim on her/his harness via the butterfly. Sliding the prussick toward the victim at this point is easy, since it is unweighted. It only takes a few inches of sliding the prussick to take the load, and then if the prussick has been properly tied and set, it takes only slight shift of position to transfer the weight of the victim fully onto the anchored prussick. At this point, the butterfly is now unweighted, so it can be unclipped and untied easily.

The next step is backing up the anchor, then setting the upper pulley on the anchor system at least a few feet above the prussick that now has the victim's weight, doing the welfare check while self-belayed with the pack-loop prussick, rigging the secondary prussick (the waist prussick loop) with the lower pulley, and beginning to haul. You can at this point convert the upper pulley to a self-ratcheting system or hand-shift the original footloop prussick to lock each sequence of raising the victim.

Here are some websites that illustrate the C-Z system fairly well:

http://newsfrompaul.blogspot.com/2005/09/crevasse-rescue-cz-haul-system.html

A 4-part set of videos:

http://www.youtube.com/watch?v=VbJ2Y3t_NkA

http://www.youtube.com/watch?v=Z07LXfplRNs

http://www.youtube.com/watch?v=EhlanzaBtp4

http://www.youtube.com/watch?v=sF4kETlz3kk

A somewhat amusing video that does cover many of the main points (from EpicTV): http://vimeo.com/57579643

And for the oldtimers who got here from the original rec.climbing.useful (one of the two predecessor forums that became Trailspace), here is High Ice Alaska's current website (John Bradford, who christened me with the "OGBO" appellation)

http://www.angelfire.com/ak4/HighIceAk/Why.html

10:18 a.m. on March 5, 2014 (EST)
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Should have mentioned, Ice Dawg, John Bradford's web name, started High Ice Alaska back in the 1990s.I think he still works at Alaska Mountaineering and Hiking, best climbing shop in Anchorage and probably all of Alaska. It is diagonally across from the REI on Northern Lights. For some reason , that REI has a major lack of climbing gear. But just walk a block to AMH.

9:21 p.m. on March 5, 2014 (EST)
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Thanks bill, helpful as always. I'll have to post a video of us practicing the rescue to show you what I mean by the loaded butterfly.

Yes the prussick would take the load once the anchor is set up, but the load that the butterfly takes pulls that sucker so tight and untying it after it was loaded just moments before was certainly far from easy during practice. That was what sparked us to try a new knot that once off the biner would just slip out of itself.

10:25 a.m. on March 6, 2014 (EST)
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One of the advantages listed in knots books for the butterfly is that it is easy to untie. Usually for a crevasse fall, you are traveling with some spacing between people on the rope, 30-40 feet. There should be very little slack between the climbers. When the victim falls in, s/he shouldn't drop very far. That plus the friction of the rope on the glacier surface and over the lip should no put much of a shock on the rope, so the butterfly should not tighten up much. The rope is dynamic after all, and when the belayer drops into self-arrest, that makes things even more dynamic. You would have to put a huge load on the rope to tighten it. Yes, there are the cases when you are descending a steep slope and someone drops into a slot. But in that situation, the whole group is likely to get pulled off, so you should be moving one at a time and belaying. Or you should be rigging rappels. Only time I have seen a butterfly get tightened so hard that it was hard to untie was in a direct shock-load. If I hang directly on a rope with a butterfly (even an Ice Floss single strand) and bounce, the butterfly is still easy to untie.

So how much of a free fall are you getting during the practice, how much weight on the victim, and how far across the glacier surface is the rope on? Other question is, if the drop is producing that much shock-loading, what is it doing to the victim? I hope you are not using a real person, if it is that much loading.

When you make your video, be sure to show everything you do to set up and to simulate the victim dropping into the crevasse. Something just does not seem right here.

1:19 p.m. on March 6, 2014 (EST)
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iClimb I see your point about trying to untie a loaded butterfly knot. 

I know that some people put several AB knots in between themselves and their partner hoping that the knots will add friction to the crevasse lip during a fall.   These people, I hear, use the loops in the AB as a place to pull from during rescue.  The book Bill mentions doesn't show that technique.  Neither does the Falcon book on Crevasse Rescue (I don't think MFOTH does either as I recall).  Still though, while setting up your Z-pulley, if you come up to a knot it should not take too much effort to pass it once you practice once or twice. 

The AB is pretty hard to beat though, trying to circumvent it seems like a solution seeking a problem.  

Pulling a carabiner out of a hitch to untie it will shock load the rope/anchor; we aren't supposed to do that. 

6:47 p.m. on March 6, 2014 (EST)
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The book Jeff mentioned is actually in 2 versions, both by Andy Tyson and Mike Clelland. Mike is the guy who draws those marvelous and very clear cartoon-like illustrations in a bunch of books on climbing, backcountry skiing, and ultralight backpacking, along with some othe outdoor topics. The first version is titled The Illustrated Guide to Glacier Travel and Crevasse Rescue, published in 2000 by Climbing Magazine. The second version, published first in 2009 was published by Falcon Guides, and is the one Jeff is referring to. You may very well find Mike's illustrations easier to follow.

Jeff suggests passing the knot around your pulley (or carabiner if you don't have pulleys). Passing knots is a skill all climbers should have in their bag of tricks, if for no other reason than to avoid getting into the Yates/Simpson Siula Grande situation.

Are you trying to untie the butterfly while it is loaded? If you set your anchor correctly, so the first prussick is between the butterfly that the belayer is clipped to and the victim, then tension the prussick onto the anchor gradually making sure the prussick does not slip up against the butterfly, you will be untying an unloaded butterfly, which should be pretty easy unless you have somehow shockloaded it. In which case the belayer is probably hurting badly.

Make the video you suggested, being sure to show all aspects of how you simulated the glacier fall.

4:45 p.m. on March 7, 2014 (EST)
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August 21, 2014
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