...but the biner was only through the rubber tip of a petzel spirit and not through the actual draw...

I don't think this is really feasible. If this were the case, I don't think the rubber piece and carabiner would stay on the draw while bouncing around on a harness, let alone when clipping a rope to it.

If you loop back over one side of the sling and clip it back through the carabiner it looks like it's OK, kind of. In reality the rubber string is the only thing holding weight.

At the top of Rico is a small ledge to stand on and clean. If you're not fully weighting the system these rubber strings will hold about 15 pounds before breaking. I'm guessing they were able to hold just enough weight to feign security while she untied to feed. Until just enough weight was added to break.
I know this is hard to visualize. It took us about 30 minutes to figure it out. Check out this video for a clear visual:

http://www.ukclimbing.com/videos/play.php?i=20

I don't know how to make it 'clicky'.
Again, there is some level of speculation but with the evidence at hand this seems to be the most likely scenario. Now sure it seems like this could be possible on one side but two?

This is where the tragedy truly lies. The fact that this happened on both slings simultaneously is one in a million.

She had two thin dyneema slings girth hitched to her harness

One possibility is if she were carrying her slings doubled on her harness

Could you explain how you double girth-hitched slings?

Wow! super sad events.

If you want to fix dedicated biners to slings use hockey tape and wrap it through the biner and then back around the sling and then through the biner again and back around the sling. Dedicated biner is now fixed on the sling in a way that it can not get in a funky possition.

When I came across the blurb in the new NRG guidebook about how NRG has had many close calls but no fatalities yet......

tradmanclimbs - that's great advise. If the leader is rigging to lower off there is no need at all for a signal from them until they are ready to lower. I watched it happen last time I was climbing in Vegas. Leader gets to the top, clips in and yells down to his belayer that he's off. Belayer confirms and takes him off and goes over to put on his shoes (or whatever). A minute later the leader yells down, "Ready to Lower" and comes within 3 seconds of decking.

Go to my blog (http://blog.trango.com/) where I posted method I use to rig a sport route that solves many problems. I'd love to hear what you think.
Mal

jay. I did not see how my tape system could replicate by looking at the petzle sketch? I think I see what you mean but it would be very obvious.

This is my first time posting on here but I had to say something since this is something I can relate to.

Could it be possible that the problem happened even before she left the ground? I mentioned this accident to someone and said something about the slim chances of both biners accidently looping back thru. He promptly put on his harness, stuck a couple of petzel rubber grips on two slings with biners and girth hitched them to his harness. As he went to clip the biners to the back of his harness there was enough slack in the slings that the biners (quite easily) looped back thru the sling.

At that point a light bulb went off. Often, when I girth hitch my slings before I climb, I'll get halfway up the route and notice one (and a few times both) of my slings dragging down. It's always been a mystery to me how this happened (I obviously wasn't thinking hard enough about how it would happen). They would be "attached" when I started (or so I thought). I don't use the petzel band on my long slings so it's never been an issue, but it certainly would have been if I had.

You might be on to something.

Jay

Assuming that these configurations are equally likely, the probability of both slings becoming configured in the failure configuration is just 1 in 4.

I just pulled one of those off of a friends sling yesterday. She had it installed correctly, but wanted to use the biner in the end for something else. She pulled it out leaving the String on the runner. I could see how you might clip into that incorrectly upon a later date.

I agree that it is unsatisfying to suppose that each mis-configured sling an independent event with a 1-in-1000 chance of happening. But then again, a systematic error alone doesn't completely explain the accident either:

I suspect that most climbers, usually, test their anchor system with more than enough weight to break a Petzl STRING (Petzl appears to capitalize the product name) in this configuration, before committing to it.

Even allowing for the possibility of some systematic error on her part...

I think that one also needs to also suppose that Karen adopted her flawed routine recently enough that she had not yet discovered this possibility.

Also, although it is a bit of an aside, if one wishes to apply more precise statistics, it is worth noting that repeatedly doing something that is unsafe in a way that allows a single anchor sling to fail like this with probability p, gives a probability of p/(2-p) that both STRINGs break, when at least one of them finally does break. (That's assuming that every time one weights the anchor, both slings are weighted enough that any mis-configured STRINGs do break.) So, even repeatedly clipping anchor bolts in a way that gives a 1/2 chance of clipping each bolt in an unsafe way (such as what Jay describes) will, 2 times out of 3, result in only one of the STRINGs breaking.

Never girth hitch or tie knots with those skinny dynema/spectra slings. They can act like a wire saw and cut through themselfs or nylon.

I may be missing something.

No, no one tests their connection to a sport anchor, ever. At most, you inspect the bolts, but you assume implicitly that the draws or slings you're connecting to the anchors are 100% reliable. The only way to test the slings would be to rely 100% on the belayer, but it's the other way around: you use your complete confidence in the slings (and the bolts) to test the belayer!

Knots in dynema slings typically reduce their peak strength by almost half. While it most likely wont kill you it is best to be avoided.


I'm sorry Jay but you do seem to make baiting comments with regularity. I most certainly do test my connections to sport anchors for body weight before going off belay.

There have been numerous death reported on this site when people fail to test their new safety attachment with body weight before removing their other safety. This happen alot in rappel accidents.

So do you also test your harness, your rope, and every carabiner on your rack before you rely on them, or do you actually assume that these elements of the protection system will work as advertised, and as they have every other time you've relied on them?

Jay

No, no one tests their connection to a sport anchor, ever.

Never untie from the rope, even when threading the shuts at the top.

No.

But I'm not sure why that is relevent.

Because her connector to the anchor fails. No one checks their connector to the anchor.

You can't check every element of the system. You have to assume that some element is the bombproof gold standard. The only way to check that the connectors are ok is to rely 100% on the belayer; but, in my opinion, the belayer is much more likely to fail than two independent connections to the anchor. So, by testing the anchor by reference to the belayer, you would actually be increasing the chances of an accident occurring.

Knots in dynema slings typically reduce their peak strength by almost half. While it most likely wont kill you it is best to be avoided.

I wholeheartedly disagree.

No, no one tests their connection to a sport anchor, ever. At most, you inspect the bolts, but you assume implicitly that the draws or slings you're connecting to the anchors are 100% reliable. The only way to test the slings would be to rely 100% on the belayer, but it's the other way around: you use your complete confidence in the slings (and the bolts) to test the belayer!


I think that sherpa79 has identified, as confirmed by ensonik, a highly plausible way that the slings could have become configured in this failure mode. The mechanism is systematic insofar as it involves clipping the "Stringed" biner into a gear loop, and random insofar as happening to catch a single strand of the sling while clipping.


I think that one needs to consider that Karen might have adopted a flawed routine recently, but the fact that—if sherpa79's mechanism (or one similar) is correct—there can be a large random element to the mechanism, could mean that Karen had been following the same practice for a long time. In sherpa79's mechanism, for instance, one could clip the Stringed biner to their gear loop many times without ever catching the correct single strand needed to cause the failure (and it is just one of the strands; catch the other, and you're fine. And moreover, whichever strand you catch, the result looks similar, so actually having caught the wrong strand before, and having experienced no problem, could lead one to shrug off the dangerous configuration.)


Maybe it's the beer I just drank, but I don't follow this at all. If the probability of making an error with either sling is p, and the errors are independent, then the probability of making an error with both slings is p^2.

Jay

No, no one tests their connection to a sport anchor, ever.

Jay, anyone who does not weight their attachment to the anchor before yelling Off and again weight their rappell before unclipping from the anchor is liveing on borrowed time.

Possible that you sport climbers get into a few bad habits due to the routine of yo yo ing?

strings and like devices place a serious flaw in the system when attached to any sling that isn't stitched shut like a dog bone.

I wholeheartedly disagree. Knots will decrease the strength of any sling. A dyneenma sling is rated to around 22 KN, a force I do NOT want to ever feel. In fact, half of that will probably cause your body damage. There is no reason to avoid using material other than 7mm nylon cord for applications such as anchors, which require bends and knots in the rope. People do this all the time, and it is safe. Feel free to back up your reasoning with something, I offer this

http://www.alpinist.com/doc/ALP18/newswire-dyneema-broken-sling-report

Although that really shouldn't be needed.

First of all, my condolences to Karen's family and friends.

Second, knots in nylon slings have been found to slightly increase their strength as demonstrated by DMM: http://www.dmmclimbing.com/video.asp?id=5

Jay, anyone who does not weight their attachment to the anchor before yelling Off and again weight their rappell before unclipping from the anchor is liveing on borrowed time.

Possible that you sport climbers get into a few bad habits due to the routine of yo yo ing?

Hmm. Clearly, there has been a miscommunication. By "test", I just mean, "weight". Are you saying that you are always able to stand at the anchor without weighting either your anchor draws or the rope?

Certainly most sport anchors get tested by way of weighting them. But I have never consciously thought of this as a testing process. For instance, when I can stand at the anchor and thread for lowering without weighting the anchor, I don't purposefully weight it to test it; I check the bolts as best I can, and double check my connection to the anchor before going off belay. Apparently, this revelation has raised a few eyebrows: a few people have commented that they always purposely weight the anchor before going off belay, and one has intoned that I am living on borrowed time.

Jay

jay, this has nothing to do with trusting the gear unless the gear is obviously suspect. It is a physical test to make sure that you are clipped in properly.

Weighting the anchor before you yell OFF...gives you a much greater margin of safety.

I don't need a physical test to see if I'm clipped in properly. I can verify that visually.


Actually, I don't see the logic behind testing the anchor before going off belay. Let's say I've just led a sport route, and I have clipped into the 2-bolt anchor using two redundant and independent connections (ie, quick draws). If I were to now test the anchor before going off belay that would imply that I trust my belayer and the single bolt below the anchor more than I trust a redundant connection that I myself made to a two-bolt anchor. To my way of thinking, the latter is more reliable than the former, so it doesn't make sense to use the former to test the latter. The same logic applies when I am ready to lower. I use the anchor to test the belayer; not the other way around.

Jay

What i am getting at is testing the belayer, the anchor, and your connection to the anchor and the whole system.

Again jay, I am testing the entire system not just one part of the system.

jay, I trad, Ice, aid and sport climb. I do not change my procedures all that much from style to style.. I keep the same drill and keep it simple but obviously there are going to be some differences due the changing situations.

Regarding sport climbing, chances are very near 100% that the top bolts will be good so the test is purely about makeing sure that your connection to those bolts is correct.... Chances are very good that had Karen weighted her slings before going off belay we would not be haveing this conversation which makes your resistance to this concept somewhat puzzeling?

One of things you are suggesting is to use the belayer and the single bolt below the anchor to test a redundant connection to the anchor itself. The current accident notwithstanding, a redundant connection that I make to a solid two-bolt anchor is going to be more reliable than a belayer catching my fall onto the single bolt below. I don't see much value in using a less reliable system to test a more reliable one—and that is what you are suggesting, whether you realize it or not.

On most sport climbs, one has no choice but to weight the anchor before going off belay anyway, so the issue is largely moot.

Jay

Jay i don't think you are understanding what Tradman is saying.

He is talking about weighting your personal sling anchor before untying.

in steps...

Take: hang on rope, clip in with sling
Slack: loosen rope so that you are 100% on sling. this is when you are sure that your connection to the bolt is good.

One other critical thing that is being tested is makeing shure your belayer is on the same page and ready to lower you. By yelling Take after you have re threaded and BEFORE you unclip you are makeing certain that Jimmy is actually ready to lower you and not chatting up Suzy firm buns and thinking that you wrer going to rap instead of lower.

Again this should be first grade level sport climbing.

If you move a computer file from one drive to annother do you just look at the icon in the new location or do you physicaly open the new file before you delete the old file?

Everone except for you jay. And we all know that You know everything

Things are not always what they seem. That sling you just clipped to that big fat bolt may just be connected to your gear loop under your windbreaker instead of to your belay loop.

stuff happens. that is why simple tests are good.

I know the gear loop wouldn't break in a quick test but it does tug you in a diferent spot than your belay loop and give you a heads up... stuff happens....