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cliffhanger
Trad climber
California
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Nov 12, 2011 - 03:01pm PT
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Ed Hartouni
Trad climber
Livermore, CA
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Nov 12, 2011 - 03:58pm PT
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Good words on rappelling, certainly one of the more dangerous things we do. It is strange what we'll rap off of, and memorable.
The 2010 Accidents in North American Mountaineering (ANAM) lists 350 accidents with "immediate cause" being "Rappel Failure/Error" from 1951 to 2009, nearly 60 years, with an average being 6 such accidents a year. It is the 8th ranked "immediate cause" just after "Avalanche" which is rather strange since climbers have almost complete control over the rappel, while avalanches tend to have a large aspect of uncertainty not under the control of climbers.
Part of a good safety program is describing "lessons learned" regarding accidents and reading them! so go out and get that ANAM and you'll learn things you don't actually have to experience, and kudos for those willing to report their accidents too. There are four rappelling accidents described in the 2010 ANAM.
One thing I tell all my partners is that we depend on each other for our safety, if you don't understand something that you see in an anchor, ask about it. It doesn't matter how long I've been climbing or they've been climbing, take the time to get it right, double check, have you partner check, talk through what's going to happen, etc... as Jim said in the OP, there is no room for failure.
This has been a topic elsewhere on STForum before, but it is always a good thread whenever it appears.
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KabalaArch
Trad climber
Starlite, California
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Nov 12, 2011 - 06:41pm PT
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Diagnostic on the photo above:
The rope appears to be running through 2 chain links!
Neither of which shows too much diameter. The lowermost chain link is not even the diameter of a ring!
So, what did you think would happen? If you think the hangup was due to the tape at rope's end - back to your gym!
...if I don't hear any beta about the Muntner Mule, I'll have to assume no one here knows wtf I am talking about. In which case, you are all subject to a new thread.
..or, of course, you're always welcome to figure it out for yerself in the field.
Going back to study the photo, it looks like the rope has been threaded to create sort of an autoblock, causing the rope to become jammed between two chain links, of different lengths pulled tightly together.
For example, had the rope been fed through the left hand link, then the right- from above, and not from below, the RH link, it probably would not have pulled the 2 bottom links together in such a manner to pinch the rope.
Or, we might have thought of threading the cord in the opposite direction, counterclockwise, first through the shorter RH link, continuing left through the LH link.
Instead, it looks like the rope was fed right to left through the upper link; the rope pull doubled the right link onto the left to form a zee through the upper link, pulling the 2 chain links together to pinch the rope between the 2 bottom links.
So, I guess my 2nd op-ed is that the rope appears to have been threaded incorrectly; a classic "pilot's error."
BTW, the reason I always rig to pull on my 8mm pull cord is because I'd much prefer the thicker 10.5mm line to be the one which takes the doubled bend through the rap slings, rings, bells, whatever.
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clockclimb
Trad climber
Orem, Utah
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Nov 12, 2011 - 06:54pm PT
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Others have mentioned checking where the sling goes behind a rock for worn edges. In addition to wear I have seen many slings nearly chewn all the way through by rodents usually on the back side out of sight.
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HighTraverse
Trad climber
Bay Area
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Nov 12, 2011 - 06:57pm PT
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As you're climbing the route, be scoping out the rapp route. Where are the rap stations? How are the anchors at those stations? Where could there be trouble with overhangs, water/ice, loose blocks? If the rapp route doesn't follow the climbing route where DOES it go? Talk about it at the belay changes.
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pvalchev
Social climber
Mountain View, CA / Calgary, AB
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Nov 12, 2011 - 07:46pm PT
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Nice thread, could save a life. A couple of more things I don't see mentioned:
 When you arrive at the next station don't forget to clip in!! Even if there's a large ledge to stand on... though people have forgotten to do so while standing on teeny footholds/stances..
Especially when using an overhand to join 2 ropes of same diameter, it's recommended to leave a long tail (if the knot rolls)... but make sure when you grab the ropes to put in your belay device, you are not grabbing the tail! Usually the ropes are weighed so this is very unlikely (tails are not weighted), but almost happened to me once.
When rappelling on ice off an existing v-thread, double and triple check it, preferably build your own. But on some climbs in Canada there are sometimes huge nests of v-threads so people clip existing one(s) which is fine. Make sure you are not rappelling off the tail of a cord that has frozen into the ice - someone died on Selenium falls in Banff that way a few years ago (tail was frozen in / mistaken for the v-thread and pulled out on rappel)
Speaking of ice, consider just threading the climbing rope through the hole instead of special cord... if the ice is dry and there's no chance it'll freeze inside. One less point of failure and a nicer pull (less friction), bonus it doesn't pollute the environment (hiking up a drainage in the summer reveals lots of old cord on the springs..). Of course, a screw backs up the v-thread for the first person, second pulls it out (as previously discussed)
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rgold
Trad climber
Poughkeepsie, NY
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Nov 12, 2011 - 11:20pm PT
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I know two cases of an anchor that had been tested with a non-load-bearing backup subsequently failing for the last person after the backup had been removed.
In both cases, the anchor in question held when loaded from below but failed when a direct outward pull was applied. In both cases, the last person moved up to remove the backup and then pulled straight out on the anchor as they moved back down.
Another thing perhaps worth worrying about when using this technique. In brief, try not to load the anchor in a way different from the test loads.
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neebee
Social climber
calif/texas
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Nov 13, 2011 - 12:43am PT
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hey there say,donini... a post of life...
thanks for sharing.... though i don't climb i sure apreciate all this worth...
say, i liked seeing this part, highly so:
Be vigilant, be tough. Momentary discomfort is a small price to pay when your life is at stake
happy climbing, as these "lessons stay alive" in hearts, for all...
:)
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drljefe
climber
El Presidio San Augustin del Tucson
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Nov 13, 2011 - 10:28am PT
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More attention should be paid to knowing alternatives to your primary rap device, as dropping rap devices is pretty common .
Know how to make a carabiner brake, munter, and other alternatives.
And be afraid, be very afraid. It will save your life.
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Tony Bird
climber
Northridge, CA
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Nov 13, 2011 - 11:21am PT
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rgold, you are starting an endless argument. i agree, prussik backups are worthless against lightning strikes, rabid chuckwallas and anchors which dissolve. what they do give is a measure of mental comfort for the rest of what we're up against. your life does not constantly depend on what your brake hand is doing. i'm suggesting that if you make that a permanent habit it will free up some RAM, so to speak, and take some strain off that vigilance the OP is calling for. it's the sort of thing that pays off and you never realize it.
i put the prussik on a sling to my belay loop and slide it with my nonbraking hand well above and independent of the rap device. i let it grab at the least provocation, then usually leg up and take in the slack with the rappel device to release it. if you're hanging in space, there are ways of dealing with that too. such a rig could save you from rapelling off an unknotted end, especially if you're in the habit of letting it grab when you sense mister trouble. of course, you could pull a complete darwin and slide the prussik on off as well.
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drljefe
climber
El Presidio San Augustin del Tucson
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Nov 13, 2011 - 11:59am PT
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Stich, I agree about the pita, just listing it as an option.
I don't think many newer climbers know what to do if they drop their atc.
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Ed Hartouni
Trad climber
Livermore, CA
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Nov 13, 2011 - 12:42pm PT
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knowing options is important... remembering them correctly is more important...
here is one that can help out:
Dulfersitz... not something you're likely to do regularly, but if you don't have a belay device or anything else, you can still descend the ropes safely.
http://www.traditionalmountaineering.org/FAQ_Dulfersitz.htm
Illustration by Mike Clelland From Climbing Ice, Duane Raleigh, 1995
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George R
climber
The Gray Area
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Nov 13, 2011 - 01:03pm PT
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I don't find the biner brake to be a pita at all. It was my standard rap method for a number of years and I still occasionally use it. No more of a pita than modern tube type gadgets.
G
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jaaan
Trad climber
Chamonix, France
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Nov 13, 2011 - 01:12pm PT
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Going back to that photo of the rope jammed in the chain link. If it was really threaded in the manner that the result suggests, then it was only really threaded through one chain, as it passed twice through the left one. Of course in reality, if either of the anchors had failed, it would still have held. Maybe though it was threaded through both in a normal fashion, and it was the whiplash that jammed the end into the left link? Either way, the best thing to do when you unwrap your new rope is to pull all the tape off the ends...
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HighTraverse
Trad climber
Bay Area
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Nov 13, 2011 - 01:22pm PT
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Does anyone have experience with a carabiner brake rappel with wiregate 'biners?
I always carry a few ovals because I don't trust the wiregates for a brake. Classic 'D' biners work fine and safely but are clumsy to setup.
I too am concerned about a Munter unlocking a gate and haven't used it for rappel.
I generally don't use an autoblock, which I rig below my brake to my leg loop. This keeps it out of the rapp brake.
I don't hesitate to use it if I expect anything out of the ordinary. Rapping in the dark. Unknown rapp route. Bad weather. Fatigue. Overhangs.
Know how to wrap your thigh to temporarily free your hands.
If there's any chance of rapping off the ends I knot the ends. I like the "stop knot". As if you're tying a grapevine (aka double fisherman's bend) but without the second rope.
Excellent animated knots page
http://www.animatedknots.com/alpinebutterfly/index.php?Categ=climbing&LogoImage=LogoGrog.jpg&Website=www.animatedknots.com
Earlier in this thread I posted an excellent reference comparing the DIS-advantages of the Prusik, Autoblock, Bachmann and Klemheist.
Here it is again:
http://www.chockstone.org/TechTips/ProtectingAnAbseil.htm
Note that in these tests, the Autoblock was the most reliable.
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Ed Hartouni
Trad climber
Livermore, CA
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Nov 13, 2011 - 01:36pm PT
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learned the 'biner brake from the '72 Chouinard catalog:
http://www.climbaz.com/chouinard72/ch_page44.html
there is a lot of improvement on this system since that sketch was made... e.g. two 'biners to connect to your harness, opposing gates, two 'biner brake...
but the prussik backup was state-of-the-art then... and probably the most unused part of this system...
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KabalaArch
Trad climber
Starlite, California
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Nov 13, 2011 - 01:55pm PT
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- the Muntner Mule rig I mentioned was not intended for use as the primary rap device, but as a means to briefly hoist your full body weight a few inches above the anchors, just for enough time to clip into your rap device.
Rapping from overhanging sling belays is another proposition compared to rapping off a slab, or a vertical wall with a foothold at the stance.
OT-we always used a fisherman's bight, or a pair of figure 8's, to tie the two rap lines together. Mostly 'cause we were scared about the stability of the knots.
But Urmas demonstrated a neat knot to serve the same purpose - a simple overhand. See, no matter how the rope twists en rappell tout en suite, or when retrieving, the knot and its tails will always flip up and away from the stone. Minimizing potential hangups when the lines are pulled down.
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jaaan
Trad climber
Chamonix, France
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Nov 13, 2011 - 03:01pm PT
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The Munter hitch, as well as figure 8 rappelling devices, tend to introduce twists into each strand of the rope, as well as twist the two ropes.
Ignoring the fact that the photo above shows the rope running next to the screw gate (in fact in Stich's photo it would tend to tighten it, not unscrew it), holding the control end of the rope down by your side in a regular rappelling position does two things.
1) It ensures that the rope will twist and of course this is worse if using two ropes to rap with.
2) It reduces the amount of friction that a Münter hitch can apply.
The way to correct both of these things is to hold the control end of the rope up parallel with the rope going up to the belay. This is done by putting your left hand (say) around both ropes above the biner and feeding slack up to it with your right. This congiguration will not twist the rope and will also work with double ropes. Holding the ropes in this manner is so effective that you can stop simply by squeezing the ropes together with the control hand. It would certainly be my first choice...
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cliffhanger
Trad climber
California
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Nov 13, 2011 - 03:05pm PT
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The Munter Hitch seems like it puts alot of extra wear on the rope.
The Dulfersitz is not only painful, it is unsafe.
Even if you have just 1 biner, the carabiner wrap is much superior to the Dulfersitz.
http://storrick.cnc.net/VerticalDevicesPage/Rappel/Carabiner.html
Clipping the ends of the rap ropes to the harness is a sure way to avoid the ends getting jammed somewhere and you can't rap off the end.
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Texplorer
Trad climber
Sacramento
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Nov 13, 2011 - 07:15pm PT
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One of my favorite rappel anchors set up after a Redrock FA. Now I hear someone placed bolted anchors instead.
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