/ 2 person glacier travel ropework

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RyanOsborne - on 24 Apr 2012
Apologies if this has been covered before, I can't find a definitive answer anywhere.

I'm heading to the Alps this summer as a two person team. I've been reading up on glacier rope work and crevasse rescue for two people, and there seems to be a consensus that with only one person catching a crevasse fall, it is a good idea to knot the rope. I've seen diagrams stipulating that for a team of two, spaced 15-20m apart, about 5-8 knots is about right.

It seems that traditional methods of getting someone out of a crevasse (prussiking up the rope or a z-haul system) become very cumbersome when you introduce knots tied in the rope.

Would a better option be to tie the knots at a closer distance (say 1-1.5m) so that the person in the crevasse could use them to climb back out to the surface, instead of using prussiks? i.e. clip a sling to the knot tied above you, step up into the sling, clip your harness to the knot, then repeat.

This is just an idea, and I'm happy to be shot down if it's unsafe.

Kid Spatula - on 24 Apr 2012
In reply to RyanOsborne:

I've always wondered this. I've never used a knotted rope in two man groups, as me and my partner are roughly equivalent in weight. I think you have to strike a balance really. More possibility of "finding" a crevasse, knot the rope. Less likely, or crevasses obvious don't.

Off to do the Weissmies this year, which seems to be a bit more crevassey than what I've done before so would be interested in the answers.
cb294 - on 24 Apr 2012
In reply to RyanOsborne:
One standard procedureinvolves a 60 m rope, 10 m between climbers (knotted), 20 m coiled on each end. In case of crevasse fall, arrest with help of knots, put in anchors (ice screw, T anchor with axe, whatever works), and rescue partner with a 2:1 pulley (pulley lowered to climber, other end going through Kong Duck or similar fixed to anchors).

CB

Milesy - on 24 Apr 2012
What if your second has become unconcious or is too injured to assist in a hoist or to get themself out? You are then trying an unassisted hoist with even more drag and friction than normal.
MG - on 24 Apr 2012
In reply to cb294:
> (In reply to RyanOsborne)
> One standard procedureinvolves a 60 m rope, 10 m between climbers (knotted), 20 m coiled on each end.

The 20m coiled is enough, and no more, to reach the climber in the crevasse and back. Any rope stretch, knots, difference in path length and you will struggle to set up a 2:1 hoist. Just a thought.

I would be interested to hear of anyone who has genuinely managed to haul someone out of a crevasse unaided as a two-man team.

MG - on 24 Apr 2012
In reply to RyanOsborne:

> Would a better option be to tie the knots at a closer distance (say 1-1.5m) so that the person in the crevasse could use them to climb back out to the surface, instead of using prussiks? i.e. clip a sling to the knot tied above you, step up into the sling, clip your harness to the knot, then repeat.

It doesn't sound entirely unreasonable although the only person I know who has really fallen into a crevasse (incidentally expect, he says, to fall about 8m in even with a tight rope etc.) found that the rope cut in a long way at the lip. I suspect this might make climbing out on loops tricky.

jon, who may appear shortly, mentioned an interesting system a while ago where you tie on with knots on one strand of the rope spaced say 15m while the other strand is longer, say 30m, with no knots. Each climber carries coils of the longer strand to keep it out of the way. The knotted strand helps stop any fall while the unknotted one can be used for hoisting etc. Makes sense to me.
The Ex-Engineer - on 24 Apr 2012
In reply to RyanOsborne: Most of the time I wouldn't bother with knots. However, on a wet glacier with a known risk of very large crevasses I'd probably have two knots in the rope towards each end or where there was a big mismatch in weight I'd have two knots on the heavier climber's end. Bypassing the knots when hauling doesn't make things that much harder provided you practice it and have things setup with that in mind.

My logic is that I am far much more worried about breaking bones in a big fall rather than having to work a bit harder to get out again.
birdman - on 24 Apr 2012
In reply to The Ex-Engineer:

Yeah i concur, a couple of knots relatively close together at either end of the rope will mean that the knots should bite into the lip of the crevasse. Make sure that they care close enough to be used as aid in climbing out and that the loops is just large enough to take a karibiner. This will save a lot of time having to set up prussics and hauling systems.

Not sure how easy it is to haul someone out using an unassisted hoist if there are knots in the rope lower down which have bitten into the snow on the crevasse lip?

For unassisted hoists as the person doing the rescuing it's all about getting the load off you early on and making anchors / system that works first time.
Mountain Llama - on 24 Apr 2012
In reply to RyanOsborne:

Hi Ryan

I was lucky enough to spend 2 weeks in the alps with plas y brenin back in 2005, so I use the method they taught for glacial travel - approx 12m rope between u and take equal coils with prussik on. No knots and use pulley system for hauling or prussia up the rope.

Having hauled someone out of a crevase and prussiked out myself under mock conditions at la luete, all I can say is that its a easy to prussac out compared with hauling by a long way.

IMHO knots on the rope don't offer a great advantage over the risk of them catching on stuff as u walk along plus bypassing them for hauling etc sounds v difficult in an already tight situation. Wet glaciers - don't usually rope up cos u can see the cravases and the ice tends to be hard so a few knots will have little effect.

Which ever way u decide make sure u both know wat ur doing and have a practice b4 u go.

Good luck with ur trip, were u going?

Cheers Davey
jon on 24 Apr 2012
In reply to Mountain Llama:

> Wet glaciers - don't usually rope up cos u can see the cravases

No Davey, you've got it the wrong way round. You mean a dry glacier.
Mountain Llama - on 24 Apr 2012
In reply to jon: oops!
AdrianC - on 24 Apr 2012
In reply to RyanOsborne: For a 2 person team I'd suggest putting some knots in the rope - I usually just put one about 3 - 4 m from each climber and maybe one in the middle if I'm feeling worried. They do make life a lot easier for the person left on the surface. For sure they mean that the accident rope (the one you caught the fallee on) is not much use for hauling with but then 1. It is probably quite well buried in the lip anyway and 2. You're probably going to use a drop-loop system in summer - so it is irrelevant once you start hauling.

15 - 20 m spacing is quite a lot. If you're in an area with really big slots you might need to be that far apart but 10 - 12m is more common.

In reply to MG - it is perfectly possible to get the other member of a 2 person team out of a slot. You're right that with 50m of rope (20,10,20) things are getting tight and in that scenario carrying a long sling and using a double-mariner system (5:1) is a better option as it is very rope-efficient.

With 60m of rope a drop-loop with a 3:1 pulley, giving 6:1 works well. You can also do it with a simple 3:1 but you need to construct a very low-friction system for that to work.

The big thing with all these systems is to spend the time to prepare the lip - dig away any overhanging snow and put an anchored axe across where the haul rope will go to reduce friction and prevent it cutting into the lip.

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