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HighTraverse
Trad climber
Bay Area
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"nothing we do is routine." boy, ain't that a trap awaiting all of us!
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rgold
Trad climber
Poughkeepsie, NY
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As often happens, language that once had a precise but restricted meaning gradually gets used in wider contexts and so loses meaning.
"Gate flutter" originally referred to very rapid small amplitude gate vibrations observed on high-speed video during some drop tests. Of course, the fact that the gate was even partially open for a fraction of a second, reduced the carabiner strength considerably.
It later became unclear whether gate flutter ever happens in the field, because it turned out that it was associated in the tests with the fact that the weight that was dropped rode in tracks, and some of the weight-track vibration interaction was transmitted to the rope and carabiner. When the dropped weight was entirely free, the gate flutter was no longer observed.
A second and completely different phenomenon is what, for lack of a better term, I'd call "gate rebound," which is an inertial phenomenon that occurs when the carabiner smacks into something and the gate keeps moving. This is easily demonstrated by smacking the back of a carabiner against your palm. The linked video shows it too, and I don't think it really matters how the carabiner is held. In any case, you don't need to have a video to know that the lower the mass of the gate, the less inertial effect, i.e. the gate will open less and snap closed earlier.
Forgetting about gate flutter, which probably doesn't happen, the usual results of gate rebound would be the breaking of a carabiner forced to endure a big load load in gate-open position. This is more likely for long runners, which provide more opportunity for the rope-end carabiner to swing into the rock hard. Still, I think it is unlikely that the rope or the sling would unclip from a gate rebound, though it is certainly possible, and of course it is even more unlikely that the rope or slings would unclip twice.
I suspect the main problem was caused by pieces blowing. There is high-speed video that shows the suddenly slack rope snaps back, going through gyrations and configurations as it does so, possibly producing the kinds of kinks and/or turns that could unclip the rope or even the sling from a carabiner without any kind of gate rebound going on.
Of course, these distinctions have no real practical value. Locking or doubled carabiners (or, if they'll fit, doubled draws as they do on the rings in the Elbsandsteingebirge) are the solution no matter what the cause. Ever since Trango came out with the original small light lockers, I've always had three or four among the free carabiners I carry---there's very little weight penalty for this. I've also sometimes racked an alpine draw with light lockers on both ends---the Granny Draw.
Sometimes it is obvious that a piece is mission-critical and deserves the locking biner treatment, but not always. Perhaps one lesson from the Crill tragedy is that the first good piece below any string of more questionable placements should be so equipped---if you are able to predict ahead of time what that anchor piece should be.
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crunch
Social climber
CO
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From Crunch:
The two biners stayed attached to the rope.
This is one part that is unclear. Before the rescuers loaded Wayne into the litter, the rope was cut short by the rescuers as it was wrapped around him and all tangled up. Minutes after the rescue left, the two Neutrino's were found sitting at the base. So they could have been attached to the rope...or not. We will never know the answer to this.
Thanks FrankZapp. I misunderstood this bit.
So, we do know that the Neutrinos did come unclipped from the slings. Possibly they also came unclipped from the rope. But for them to come unclipped from both slings and rope would be far fetched, even by the freakishly unlikely knowns of this accident.
So tragic, and on top of that, so hard to know exactly what can be learned (which is typically the one positive to come out of these horrible accidents--a lesson that may prevent further accidents)
I think maybe I'll be heading to Neptunes this afternoon to buy some beefy nylon webbing slings--to be kept resolutely slung over my shoulder--and to go with them, some lightweight, locking, free biners.
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snowhazed
Trad climber
Oaksterdam, CA
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This accident happened right before I got on Heart of Stone- many of the runouts involve traversing and so the slings were extended, I found myself opposing gates on a few bolts. Took no extra gear, just pilfered biners off my other slings, and used those single biner slings with cam placements. The piece of mind was instrumental for helping me succeed
Hope Wayne recovers
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Dingus McGee
Social climber
Where Safety trumps Leaving No Trace
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Assumptions lead everywhere and anywhere.
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Gilroy
Social climber
Bolderado
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From what I've read about the accident and reading everyone's comments, it appears to me this dreadful accident resulted from the slings looping and opening the gates. But that's just my opinion.
Carrying some lighter lockers - or doubling rope end biners - for critical placements begins to sound like a good idea.
What High Traverse said. +1
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NutAgain!
Trad climber
South Pasadena, CA
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Big +1 on using lockers or doubling 'biners for critical placements. Huge lesson I learned the hard way.
I fell and the rope came undone from the 'biner with a loooong way to the next piece below, and I took a long freefall, bounced off my shoulders and back of my helmet, and another long freefall and woke up on the ground but with rope stretch taking some of the force. I'm pretty sure it was my hand instinctively grabbing at the sling as I fell past it that caused the rope to come off the wiregate 'biner, but a locker or doubled 'biner would have spared me that disaster. Then again, maybe it would have just made the sketchy piece yank out?
The new catchphrase: "DFD" - Don't Forget (to) Double"
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WBraun
climber
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This whole discussion centers on preventing future accidents by looking for potential subtle problems that can be caused by gear.
What is really weird is this year in Yosemite we've had more climbers taking falls where they've hit the deck then at any time in history.
Most people will immediately "assume" it's because of more climbers or n00bs.
These where not n00bs.
There was something the air this year .....?
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NutAgain!
Trad climber
South Pasadena, CA
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Ho man, in a flick of a keyboard, locker turns a dark moment into a laughable one! Divine comedy.
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ericthemantis
Sport climber
Provo, UTq
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Jan 20, 2015 - 03:40pm PT
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For all you dissin on my youtube video, I don't work for a wire manufacturing company, and the video is not "100% misleading". It was just a simple experiment my friend and I undertook while in the possession of a high speed camera. We held the biners in a bunch of different ways, hitting it on our hands and on a wood block. How we held it definitely affected the magnitude of the gate movement I am sure, but the big take away is that a wire gate biner can still open on impact. We were curious, and our curiosity was satisfied.
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two-shoes
Trad climber
Auberry, CA
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Jan 20, 2015 - 03:52pm PT
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But, don't non-wire gate biners open even more readily with kinetic impacts than do wire gate biners? I believe this was what was being touted when wire gate biners were fresh on the market a number of years ago.
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Ben Emery
Trad climber
Australia via Bay Area via Australia...
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Jan 20, 2015 - 05:56pm PT
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Out of interest, is having the biner clove hitched to the dental floss sling a viable approach to reduce the biner shifting around as you climb above it/fall?
Seems it would make it less likely to cross-load etc, but perhaps a reduction in strength of the sling outweighs any advantage.
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ericthemantis
Sport climber
Provo, UT
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Jan 20, 2015 - 07:21pm PT
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@two-shoes, yeah I would definitely agree with you. I just feel like I had been led to believe that wires don't really open at all. At the same time though, for it to happen, you need a big fall, solid impact point, 90 degree impact etc. I climb on wires and solids. The wires are lighter, so I prefer them, but now recognize that the risk level is also probably the same between the two imo
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