Redundancy: Not in fashion these days?
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I was at a short "demo" of self-rescue techniques the other day, where one employee of a local guide company showed a few "tricks". He was a big fan of the "quad" (fig. 4 in rockandice.com/climbing-new… ), but also said he was perfectly happy with a single sling sliding-X with no knots (fig. 2 in the above link) clipped to two bolts as was one of the attendees. |
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Redundancy is reduced in importance when the individual component is so strong that its likelihood of failure approaches zero. |
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The real problem is making catechisms out of lists of desirable features. Redundancy is desirable but not always achievable, and in some situations of far less consequence then others. In other situations, redundancy can be situation-dependent, with the possible need for speed conflicting with the extra time needed for backing things up. |
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I once built a rescue anchor off the wheel of a fire truck using a 4" nylon strap. I was very OK with a single anchor point. |
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Firestone wrote: Ill just leave this here.Yup, which is why I said "unless the party is genuinely concerned..." The party in question had plenty of reasons to be concerned, they were doing a climb below major chossy gullies on a super warm winter day when there had been very cold and wet freeze-thaw cycles earlier in the year, so falling rock was predictably an issue. |
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RG do you have simple method for useing just the rope as an anchor when leading multi pitch in blocks? When leapfrogging I use the rope as the anchor but not when leading in blocks. |
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Firestone wrote: Ill just leave this here.If the rock had landed a couple inches lower hitting the knot or been a little wider hitting both stands the redundancy would have made no difference. They were VERY VERY lucky. This single example which is unlikely to happen again is not a strong argument for or against anything other than moving the anchor to a more sheltered position. |
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Nick Goldsmith wrote:RG do you have simple method for useing just the rope as an anchor when leading multi pitch in blocks? When leapfrogging I use the rope as the anchor but not when leading in blocks. Christopher Gibson wrote:Place a second carabiner below the carabiners that you tied the rope into and have your second use those when they get to the anchor for their end of the rope just as the leader did, now their in the anchor just as you were, when its time for you to start climbing again have your second put you on belay and grab your carabiners and go.If I'm going to do all the leading, I usually use some kind of cordelette. I very rarely do the blocks thing, but there too the cordelette seems most efficient for longer routes. For shorter routes where time is less critical and the second is of equal or better ability, I do almost what Christopher suggests above, except that the second carries their carabiners and sets up their anchor when they reach the belay. I think this is better, because it means the leader doesn't have to have double the number of belay biners when he or she arrives at the stance. And frankly, the extra amount of time consumed (assuming the second is competent at rigging) is very small. If the second has an installed tether (which I have continually argued is a good idea), then they tether in as soon as they reach the belay, hand over the rack collected on a single over-the-shoulder sling, and then build their belay anchor with the carabiners they are carrying, under the leader's anchor, while the leader is re-racking. After that, if the rope has been piled on a ledge, the second re-piles the rope. (If the rope has been flaked over the tie in, then we usually just "flip" the stack onto the second's tie in.) If the party is using a guide belay plate of some sort, then the second doesn't need a tether for this process (I still think it is a good idea to have a tether for other uses), the leader just ties a backup knot and "parks" the second on the loaded belay plate, which is retrieved after the second has built their anchor. |
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Um ? I said what I did , is that What to say to this ? |
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rgold wrote: The party in question had plenty of reasons to be concerned, they were doing a climb below major chossy gullies on a super warm winter day when there had been very cold and wet freeze-thaw cycles earlier in the year, so falling rock was predictably an issue.This goes to show me that even the pros can make mistakes. If the falling rock was predictably an issue then why did the climbers think the single sling was okay? Now that we know that even in unlikely circumstances a block can potentially damage an anchor catastrophically will you think twice about that one sling between you and the deck? climberpat wrote: If the rock had landed a couple inches lower hitting the knot or been a little wider hitting both stands the redundancy would have made no difference. They were VERY VERY lucky. This single example which is unlikely to happen again is not a strong argument for or against anything other than moving the anchor to a more sheltered position.Moving the anchor to a different place wouldn't have helped because neither climber expected a big block to pull on them. Luckily there were limited knots in the sling or else it wouldn't matter where the block hit. I have a good feeling that a lot of people are under the impression that slings are bomber and that limiter knots are either overkill or weaken the sling. |
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Scott O wrote:I once built a rescue anchor off the wheel of a fire truck using a 4" nylon strap. I was very OK with a single anchor point. It all depends on context, but if an individual component is bombproof (a rope, a belay loop, a belay carabiner), it doesn't have to be redundant. A sliding X with a good sling is fine. The real risk the knots protect against is extension rather than a concern about redundancy, but even that is theoretical with well placed bolts.There are three things that are important - judgement, awareness, and assumptions. Judgement in what is appropriate for the current situations ("context") and risks. For example, if a thunderstorm is soon to hit, faster, simpler, "less safe" methods may be appropriate because the biggest risk is from lightning. Awareness in that you are CONSCIOUSLY changing methodolgies because of the current situation. Be AWARE that you are accepting more risk, or you are changing the types of risks, and aware of what those risks are. Be aware of the assumptions you are making, like "well placed bolts." How do you know they are "well placed bolts?" The single anchor on a fire truck was very strong, but there have been incidents where somebody jumped into the truck and started moving the truck - were the keys left in the ignition? The thing that happens may not be what you expect. Todd Skinner died when his belay loop failed. Black Diamond recently recalled many of their carabiners. Flaws in equipment are often not revealed until failures in the field by people using the equipment. So, my default is to have redundancy in my system. There are many arguments on MP on what is "best," and people get insulted if you choose a system different than theirs. Just because somebody chooses a system different than theirs doesn't make theirs wrong or that you are stupid because you didn't choose theirs. I use equalettes and sometimes just a cordlette. I use a quad on two bolt sport anchors. I don't use sliding x's because testing shows sliding x's lock when shock loaded and so they don't equalize. Equalettes do not equalize the load in many situations, but do provide redundancy. Take what you like and ignore the rest. The best system for YOU is the one YOU understand and that works for the kind of climbing you are doing. "Understand" means you know the advantages, disadvantages, assumptions and risks of the system you use. AND you know how to rig the system. |
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Just take 5 seconds and tie two knots in it...every time. No judgement needed. I do it 100% of the time and haven't had a forced bivy due to wasted time yet! |
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Arlo F Niederer wrote: there have been incidents where somebody jumped into the truck and started moving the truck - were the keys left in the ignition? The thing that happens Todd Skinner died when his belay loop failed.Black Diamond recently recalled many of their carabiners. Flaws in equipment are often not revealed until failures in the field by people using the equipment. So, my default is to have redundancy in my systemsIt is very important to be sure to say that T Skinners belay loop failure was due to the physical process of WORK, extreme use, and the lack of a second piece of cord or tape. It was not due to product deficiency. Nor did it happen during the proper use of the belay loop. |
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Michael Schneider wrote: It is very important to be sure to say that T skinners belay loop failure was due to the physical process of WORK, extreme use, and the lack of a second piece of cord or tape. It was not due to product deficiency. Nor did it happen during the proper use of the belay loop.I used two examples - one with old gear (Todd), and one with new gear (Black Diamond carabiners). Todd ASSUMED it was O.K. - if you don't inspect your gear then you are assuming it is good. My point about being aware of the assumptions you are making - we often make assumptions without even realizing it. It's OK and necessary (climbing rope) to have a single point of failure in the system. But you must inspect all the single failure elements! If Todd had redundancy he would still be alive. We assume that new gear is good, but even that assumption may be false. I'm not a worrywort, but I try to be aware of the risks and reduce them if I deem it necessary. Redundancy reduces the risk of manufacturing defects - which are rare - but the consequences are bad in case of a failure. |
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Firestone wrote: This goes to show me that even the pros can make mistakes. If the falling rock was predictably an issue then why did the climbers think the single sling was okay? Now that we know that even in unlikely circumstances a block can potentially damage an anchor catastrophically will you think twice about that one sling between you and the deck? Moving the anchor to a different place wouldn't have helped because neither climber expected a big block to pull on them. Luckily there were limited knots in the sling or else it wouldn't matter where the block hit. I have a good feeling that a lot of people are under the impression that slings are bomber and that limiter knots are either overkill or weaken the sling.It is important to place your anchors considering the rockfall potential. I try very hard to place bolted anchors in protected locations such as under an overhang, where there is a turn in the route or a couple of feet off to the side of likely rockfall. I also try to place trad anchors in relatively safer positions and have bypassed the documented locations and bolted anchors because of the rockfall danger. The point is to anticipate rock fall and do what you can to mitigate the danger. I understand that you believe that you are significantly safer by tieing limiting knots in the sling and I agree that the knots make the anchor marginally safer (not enough for me to care either way). However the climbers who survived because of those limiting knots were extremely lucky; not alive by any skill on their part. Almost any change in the belay anchor position, belayer position, weight of the rock, energy the leader applied to the rock... could easily have changed the outcome for the worse or better. I believe your are much better off looking holistically at the situation and there are often other changes that have a much greater impact on safety than limiting knots. This may be the only example of where limiting knots made a difference. Certainly the only example I have heard of. I regularly climb routes with high rock fall potential. Moving the anchor to a 'sheltered position' makes all the difference. It is also important to only place gear in solid rock. Don't place gear behind loose blocks!!! As far as redundancy goes. Redundancy is nice but if you examine the process of climbing a pitch (especially first ascents, but also many established climbs) there are lots of times when the failure of a single piece of gear will be disastrous in case of a fall. Watch someone climb a pitch and imagine them falling at every move and their last piece of gear failing. How often will they hit the ground? Falls can be disastrous even with no failures (X rated climbs). Many climbers are alive today because they did not fall at a critical point. |
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Dana Bartlett wrote:A sliding X with two bolts? Why?I don't like sliding X but how do you have a single bolt sliding X? The point is auto auto balancing between 2 points but it comes at the loss of redundancy. Yes I would agree they are pointless because the sling itself I would assume fails more often than the bolt. |
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I don't think Dana was implying you should use a sliding X on a single bolt. Rather, the point was that each bolt is solid enough to hold without equalization. |
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Dana Bartlett wrote:A sliding X with two bolts? Why?Not equalization, speed, especially if the two bolts are not at exactly the same horizontal level. Don't get me wrong, I don't use sliding X's for anything, but that's why some folks might. |
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RG, thats kind of what i thought. we did a lot of fast and light this summer and both used the rope to anchor when leapfrogging but were reduced to useing slings when one of us did not feel up to the next lead. a lot of that time you saved gets lost when one person gets sick or otherwise feels they can't take their lead and the rope is all tied up in the anchor. |
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Nick Goldsmith wrote:a lot of that time you saved gets lost when one person gets sick or otherwise feels they can't take their lead and the rope is all tied up in the anchor.Simple solution to avoid that. Swap ends of the rope. Also means that you don't need flip or re-flake the rope. Shouldn't take much over a minute. Obviously at least on person needs a sling to make themselves safe while they untie. I use the rope for the anchor 95% of the time. Even if I'm leading all the pitches then I will still do so. The main times that I don't use the rope is when there is a bolted belay and my 120cm nylon sling will do the job. (Though me leading all the pitches normally means my partner is significantly lower ability so the expectation of rapid belay changeovers and fast climbing is not there.) |