2 person Crevasse Rescue

[AlpineClimber]

So I've been seeing quite a few people on various glaciers this year, heading up in 2 person teams. While I am not completely opposed to this idea, it does raise some moderate concern on a rescue situation.

 

I consider myself fairly schooled in Crevasse Rescue and Z-Pulley 3:1 for 3 person teams for these types of situations, but it becomes much more difficult to conduct a self rescue if there are only two of you. (Consider last week's incident on the InterGlacier). What do most consider to be the best course of action, if there are not people around to conduct a "Brute Force" Pull? What if you don't have a cell phone?

 

Does anyone have pointers to the best methods to use to escape the rope if this becomes the case? My initial response would be try and secure an anchor.

 

Any feedback is appreciated.

[tread_tramp]

No Cell phone!!! My God; You just better not climb. The risk factor is way over the top.

[ryland_moore]

If you practice setting a T- anchor with your axe while holding your partner, you will see that it is not impossible. Once you are able to get your partner onto an anchor system and free yourself so you can set up an additional anchor and set up the pulley system, you can actually lift someone with a 6:1 ratio using a Z-C pulley system.

[pete_a]

have a plan figured out before your partner and you rope up, such as agreeing to just hold the weight of the fallen climber for ten minutes or so before trying anything, which allows the climber in the crevasse a little time to prussik their way out on their own. hopefully they're not too banged up to not help get themselves out.

If the time has passed and you have to extract them on your own, hopefully you have your picket(s) very easily accessible and can access them with one hand, as you'll have the other hand on your axe until you can get a decent anchor to transfer the weight to.

Once the weight is transfered, you'll need three of four items that can be used as anchors (even deadmanning stuff sacks or making bollards would work) cause if you're really going to try to haul the person out, you'll likely need to rig a double Z-pulley or C-Z to get a mechanical advantage that would allow a single person to haul another out.

Elaborate setups like that take a lot more time to rig and the prussiks/pulleys need to be re-set twice as often, but its probably the only way unless you're really strong or your partner weighs 100lbs.

[Lambone]

Whats the best anchor to set up to get the initial load off the arest/rescuer?

 

Ryland-what do you mean by the "T" anchor?

 

I've practiced this and found it very difficult to get a picket in if the glacier is solid at all....but not solid ice for screws...

 

I don't know, seems like getting that anchor in is the crux.

[AlpineClimber]

I would think a single picket driven down into the snow, and a prusik attatched to the runner on the picket would suffice.

[Lambone]

yeah, but ever try to drive a single picket straight down into hard snow, with one hand, while lying on your belly? Can't use your axe to drive it cause your arresting with your axe...

 

And if the snow is soft enough to just push it in with one arm in that weird position, will it really hold your partner?

 

Much easier said then done.

[AlpineClimber]

True Enough.

[jaee]

Lambone, by T I think he means a deadman anchor using the axe.

 

A single picket driven into the snow would be good only for the static weight of climber while you are escaping from holding the fall. Unless it took a hammer to drive that picket you'll want to add more points of pro to extract the fallen climber.

 

With a C on a Z you've got a 6:1. That means the forces on the anchor will be in excess of 6x the climber's weight. This is where you'll want to at least double up the pro. Typically you'll need to work harden the snow and place deadman anchors to handle the load. Again, if driven w/ a hammer a couple vertical pickets would probably do.

 

There's a slick method of the C on a Z where you just add a 3rd pully in the system w/ a prussik. This has to be reset more often but is much simpler than adding another anchor for the C.

 

Also, a releasable prussik (munter mule) on the main anchor is something that everyone should use, especially in situations where there is no other help available.

 

I'll try to dig up a pic of this setup.

[AlpineClimber]

Thanks Jaee

[Coondog]

I've practiced 2 man rescue w/ kiwi coils: found trying to wiggle out of pack while holding arrest, and pounding in a picket to be a pain... but workable on moderate terrain...

 

Z+C offered plenty of leverage to pull lightweight (ex-)girlfriend up; only have 1 pulley so used ovals for rest, which is more resistant so better for bulking up your upper-body.

 

And I carry at least one screw in case you come across steep, icy terrain in which it might be near impossible to get out of arrest to pound a picket...

 

my $0.02.

 

--cd

[cmor]

I've practiced 2 man rescue w/ kiwi coils: found trying to wiggle out of pack while holding arrest, and pounding in a picket to be a pain... but workable on moderate terrain...

--cd

 

I've found the same. Usually you can drop the coils which gets the weight centered lower, and then pound in an ice tool and transfer some of the load onto that using a prussik. That should free you up enough to dig a t-slot or pound in a picket. With a little practice its not too difficult. From there drop-loops or z-drags are simple to set up if needed, although your partner should almost always be able to self-rescue.

[Buckaroo]

""With a C on a Z you've got a 6:1. That means the forces on the anchor will be in excess of 6x the climber's weight.""

 

With a 6 to 1 ratio the pulling force is multiplied 6 times and the pulling rope movement distance is 6 times the distance the load is moved .

 

The anchors will only be loaded with the weight of the fallen climber plus the friction resisting upward movement.

 

The only time you might see 6x load plus on the anchor would be if the fallen climber got stuck and you were able to exert more than the weight of the climber on the pulling rope without the fallen climber moving.

 

Reminds me of the story on Denali. Woman fell in a crevasse they set up a Z pulley and pulled her up to the roof of the crevasse and she got stuck. No one was watching her and they exerted so much force it ripped her harness and she fell and died.

[dlofgren]

Andy Selters addresses this on pages 110-114 in his book, "Glacier Travel & Crevasse Rescue".

Go up to Alta Vista in the spring and practice what he says with a partner, one throwing him/herself over the bank, the other stopping the fall, putting in an anchor, transferring the rope to the anchor, backing up the anchor, setting up a Z, etc. The key is to PRACTICE.

My partners and I have found it's easiest to have the picket with a sling with two biners carried on the side of the pack, held by the compression straps, that can be reached over the shoulder, which can then be clipped to a Bachmann pre-tied to the rope, which can then be weighted (slowly/carefully), then backed up.

The key is to PRACTICE.

Each person needs to carry a minimum of TWO anchors and TWO pulleys and a Kiwi coil of enough length to form a decent Z.

The key is to PRACTICE. Did I say that already? :-)

Caveat: I've never had to pull my partner out of a real live crevasse (happy about that) so this ends up being my two cents worth.

I also agree with Pete A that the partners should have a plan to give the person in the hole the opportunity to prussic out or to climb out if possible.

[erden]

I favor more than two to travel on glaciers.

 

That being said, I have read of people who throw in a few butterfly knots on the line between the lead climber and the second. This jams in the snow as the line cuts through the edge of the crevasse, hence reducing the forces on the self arrest that the second has to hold.

 

Transitioning to building an anchor therefore is significantly easier. This I assume would work best if the fallen climber can self extract out of the crevasse. Otherwise one has to deal with passing the knots through the pulley system, not to mention the sawed off edge of the crevasse, and wonder if the same knots will be a hinderance to the system.

 

Erden.

[wormfighter6]

T anchor is BOMBER on hard sonw or ice you have to use your axe to dig into the packed snow or ice. Put your runner in the middle of the pick with a ramp in the dirrection of the pull. Re burry the picket, unless the picket can break through 1-2 ft of packed snow the person is going no where. I've practiced it before and used it in real life situations, with the adrilin (SP?) pumping it took about 45 seconds to dig down into the packed snow. once that is done you can get off belay.

[Dustin_B]

Why all this talk of 6:1 system needed? If you have a 200 lbs climber you are trying to pull up, a regular z-pulley makes that 66 lbs. Plus some friction, say you are hualing 80 or 90 lbs out of a crevasse. I'd say an average climber working on adrenelene could haul that person out, no? Yeah, I know that is pretty damn heavy but it seems possible.

[j_b]

Dustin: there is usually too much friction in the system for a single z system. a 1:6 advantage ratio is most often not enough.

 

as for setting up anchors in hard snow: if the snow is so hard that you could not pound in a picket or an ice axe with "relative ease" it usually implies that the danger is somewhat obvious and can be readily assessed/prevented. mishaps do happen, but usually it happens to the unweary or the tired. this said, a party of 2 has undeniably less capability for rescue, that is part of the deal.

[pete_a]

another argument for carrying an ice screw or two even on an all-snow-glacier slog route is if you're the one in the crevasse and are too beat-up to ascend the rope, you can at least try to sink in some screws into the crevasse wall, clip into them and get the weight off rope so your partner can have an easier time rigging a haul system.

[tomtom]

That being said, I have read of people who throw in a few butterfly knots on the line between the lead climber and the second. This jams in the snow as the line cuts through the edge of the crevasse, hence reducing the forces on the self arrest that the second has to hold.

 

Has anyone demonstrated that this actually works?

[Jason_Martin]

I just wrote about this stuff in the Axe Length post.

 

But to answer a few questions... Butterfly knots in the rope work great. I've tested them many times and they work like a charm.

 

The problem with the knots is that on a single team rescue, either you will have to haul past the knots which requires a great deal of practice, or your partner will have to somehow prusik past the knots which is not impossible, but almost; especially if the rope has done what it is suppose to do and cut deeply into the lip of the crevasse catching on the knot.

 

Someone wrote that it is possible to pull a person out with a Z-pully by itself. While this is true, it is hard. A few years ago I lowered someone down a crevasse for ice climbing practice. The person was over sixty feet down and couldn't climb out. I hauled part of the time with a z and part of the time with a C-Z. Part of the reason I used a Z alone is because he was so far down, and the way the 6 to 1 works is that for every six feet you pull, they only move one foot.

 

That said, I got so tired I had to add the C to get the guy completely out of the hole.

 

Someone else asked what a T slot is. This is the slot you dig to bury a picket in the snow. The slot is shaped like a T.

 

I believe that with practice and proper training, travelling on a glacier with a two person team is totally acceptable. Crevasse rescue requires practice. Putting together a C-Z in the backyard every two years is not practice. Playing with the system multiple times each season in the snow is the only way to truly create a solid understanding of what to do when the shit really hits the fan...

 

Jason

[dylan_taylor]

Butterfly knots work great in most summer cascades/Alaskan snow conditions, but not so well in soft (powder/slush) or rock-hard snow. They are a good last resort for two man teams, but that said, don't go hog wild and tie too many of them. I tie one 8-10 feet from me, and one 8-10 feet from my partner.

 

A couple of other tips: So far there has been much discussion of pickets used this way and pickets used that way. What about flukes? They are way easier to place when you are lying on your belly with the weight of your partner trying to drag you backwards. Plus, they are a dynamic anchor, and will self-adjust to meet your second anchor (a picket) if they are overloaded by a bouncing (prussiking) fall victim.

 

Pickets. To avoid trouble with taking them off your pack:

Rack up tp 2-3 of them on your strong side, clip a biner from the front picket sling to the upper part of the webbing which runs down your pack shoulder harness, clip each biner from the next picket in line below that. That way they are always easy to remove, even in awkward situations.

 

Pulley systems: The more I practice it, the more I think the 6:1 Z to C is a little overrated. I think a 5:1 is way better, especially when a dynamic rope is being used, along with biners as pulleys. In a lab, under static frictionless conditions, the 6:1 is obviously better, but notice that when you practice hauling someone out, you have to pull about 5-6 feet of stretch through the system. The 5:1 has less stretch, and only one prusik to reset, rather than two.

 

On forces. No properly set up pulley system should ever multiply forces on an anchor. The only way of multiplying forces on an anchor is to set up a haul so that you are pulling towards the crevasse. This is bad. Make sure you are pulling away from the crevasse.

 

On rigging yourself for glacier travel: The texas kick is great. But one system that allows you to set up swank rescue sysems is to attach a short cordallette for your feet, and nothing for your waist. Leave a waist-prusik sizes sling clipped through one of your two lockers on your harness, and clip a locker with a tibloc to the other end, and clip this to your gear loop. If you go in a hole, it is quick and easy to pop the tibloc on the rope below your leg prusik (depending on adjustment), and start jugging.

If you have to rescue, your leg prusik gets attached to your initial anchor with a munter mule if you can. A third prusik get added where your texas waist would have been put for a Z to C, and your tibloc prusik can be used to self belay to the lip, or, in the case where you are using butterfly knots, can be added into the system in between the top pulley and your leg prusik. Once the load is transfered to the tibloc (after your knot-pass), you no longer have to tend this prusik, just haul away.

[dlofgren]

In his emphasis on PRACTICE in the snow, Jason is right on. There you learn little things like slipping your Bachmann down the rope as far as you can before weighting it so it doesn't bunch up tight against your knot and make your knot nearly impossible to untie! Not that that's ever happened to me... And you learn how long to leave the loop on the Bachmann so you CAN slip it down the rope. And why you should not tie directly into the rope because even a butterfly isn't that easy to untie after being loaded, especially if it's twenty degrees with a thirty mph wind blowing and you have to take your liner gloves off to untie it and then your fingers are useless for however long it takes to warm them again while your partner is still in the hole and by then you're so chilled you're drooling and have forgotten how to set up ANYTHING because you haven't PRACTICED! And that's real life.

[Ricardo_Montalban]

On forces. No properly set up pulley system should ever multiply forces on an anchor. The only way of multiplying forces on an anchor is to set up a haul so that you are pulling towards the crevasse. This is bad. Make sure you are pulling away from the crevasse.

 

ok, i'll admit i'm a relative newbie on the subject, but this doesn't jive.

Direction of force: even with a basic z-system the forces are pulling towards the crevasse. you are pulling away from it, but the force on the anchor is coming from the secondary pully.

multiplied force: force of haulers X force (weight) of hualee. i know this is over simplified, and someone else would better exlpain it.

 

am i out in left field here?

[cj001f]

am i out in left field here?

Force is never multiplied on the anchor with a block and tackle (which is what a Z haul is, essentially

 

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