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Gear Failure on West Face Leaning Tower results in whipper.
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By dp-
May 8, 2013
Before the draws were extended, were they tripled or doubled to shorten them? Tripled ones extend cleanly; doubled ones extend with a loop around the spine of one of the biners. Loading them with the wrap seems like a bad idea.

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By bearbreeder
May 9, 2013
dp- wrote:
Before the draws were extended, were they tripled or doubled to shorten them? Tripled ones extend cleanly; doubled ones extend with a loop around the spine of one of the biners. Loading them with the wrap seems like a bad idea.


it was the rope end that broke on both of the lower pieces ... so the wrap is irrelevant, as when you extend a draw itll be the piece side that has the wrap if anything ... the rope side will almost always be "clean" since you are clipping a single strand

the other thing to note is that the first piece was NOT a backclip, which by definition would mean the rope would unclip itself off the biner in a fall ... the biner was still attached to the rope ... i suspect the biner and sling got loaded into a position or against something where it unclipped itself

again ... where any of the biners loaded against/into a crack or some other feature?

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By dp-
May 9, 2013
bearbreeder wrote:
so the wrap is irrelevant, as when you extend a draw itll be the piece side that has the wrap if anything ... the rope side will almost always be "clean" since you are clipping a single strand.


Right...Assuming they were extended like most people do with the loop on the gear/bolt end. On the other hand, they are reported to have been dyneem slings so I wouldn't expect them to have be doubled up.

Probably a false trail since I don't know anyone who doubles their runners anymore. I only thought of it b/c there was speculation about torsion and the photo looks like there was a break where the twist usually stacks up.

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By ahh
From Bay Area
May 9, 2013
dp- wrote:
Right...Assuming they were extended like most people do with the loop on the gear/bolt end. On the other hand, they are reported to have been dyneem slings so I wouldn't expect them to have be doubled up. Probably a false trail since I don't know anyone who doubles their runners anymore. I only thought of it b/c there was speculation about torsion and the photo looks like there was a break where the twist usually stacks up.


The slings were tripled into a draw.

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By Garrett Harmsen
From Charlotte, NC
May 9, 2013
CraigS. wrote:
After reviewing the added picture of the fractured surface, the angle of the fracture, some examples from my "Failure Analysis of Engineering Materials" book, and the BD blog listed above . . . my mildly educated SWAG would be failure due to torsional stress with the gate closed that started at a notch as one person mentioned from clipping to a bolt or other similar damage. Please take this with a grain of salt as I am only looking at pictures, reading, and reviewing. I did not sleep at a "Holiday Inn Express" last night either, but I was a reliability engineer in a processing plant for a few years and had to make similar analyses. Usually, though, most of my failures were from either chemicals or improper installation/use.


I could be wrong but doesn't the 45 degree failure plane indicate that a tensile force caused the failure? Pretty sure a torsional failure would leave a horizontal failure plane for a ductile material like aluminum. This seems more likely as the climb was overhanging and not much could have trapped the biner to cause a torsional force. Somehow the gate must have opened...

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By Greg D
From Here
May 9, 2013
Out of the blue.  Photo by Mike W. <br />
The Stoned Master wrote:
Ill take this opportunity to inquire: why are wire gates superior for crossloading, etc? I use strictly wire gates myself but am unsure why they are tougher than the non-wire gates?


The wires are made of steel. Very hard to break the actual gate. Solid gates are made of alloy. They can snap . Also, the wire gates tend to have more tension. Hence, less likely to come open from whiplash and gate flutter.

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By wankel7
From Indiana
May 9, 2013
Will S wrote:
were all Mammut biners. Those Moses superlight wiregates were blowing up left and right a few years ago. I'd chalk the whole deal up to freaky anomaly...but I also wouldn't be climbing on Mammut biners anytime soon either.


I did some googling because my rack is held together with Moses biners ...

Thread with two responses from Mammut...the initial response and then a detailed one.

supertopo.com/climbing/thread....

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By justing
From Santa Cruz, CA
May 9, 2013
Arrow
The thread wankel linked to had a quote from a fellow from BD stating

"I always face the gate on the bottom (ie. rope) biner the opposite direction of the way I'm climbing (ie. route goes left, I face the gate to the right)"

Is this what others do? Maybe I'm misunderstanding what he means, but I would have supposed that this increases the likelihood that the gate comes in contact with the rock and opens in a fall.

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By csproul
From Davis, CA
May 9, 2013
Summit of Wolf's Head with Pingora in the background
justing wrote:
The thread wankel linked to had a quote from a fellow from BD stating "I always face the gate on the bottom (ie. rope) biner the opposite direction of the way I'm climbing (ie. route goes left, I face the gate to the right)" Is this what others do? Maybe I'm misunderstanding what he means, but I would have supposed that this increases the likelihood that the gate comes in contact with the rock and opens in a fall.

Think right and left, not facing out or facing in. When you clip a bolt you face the lower biner away from the direction of climbing to minimize the risk of the rope falling across the gate and unclipping itself. A much smaller concern with a flexible runner and biner free to rotate clipped to gear than with a rigid draw and rope-end biner fixed with a string.

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By rgold
From Poughkeepsie, NY
May 9, 2013
The traverse out to the Yellow Ridge on the Dogstick Ridge link-up.  Photo by Myriam Bouchard
If you trace through the various threads on biners breaking, back to Chris Harmston's comments from rec.climbing, you discover that biners do break and this current instance is not the first time there have been multiple breaks in a single fall.

It is nearly certain, except in cases everyone has been taught to avoid (such as levering a biner over a horizontal edge), that broken biners result from open gates. Gates can be opened (1) by direct contact with a rock feature, (2) by hooking on a bolt hanger, (3) by momentum effects when a biner strikes the rock, (4) by the somewhat mysterious phenomenon of "gate flutter" in which the combination of rope stretch and running rope sets up vibrations that periodically open the gate, and (5) by being in a cross-loaded position that applies the load directly to the gate.

Direct contact, either with rock or bolt hanger hooking, can often be anticipated and adjustments made. Momentum and flutter openings can be reduced, but not eliminated, by using wire gates on the rope end. Cross-loading is very rare because the biner is usually able to orient itself under load.

Gate flutter seems to be enhanced if there are multiple gear failures and so may be an explanation for otherwise mysterious breakage during zipper falls. If the belayer is off to the side of the climbing line or if the rope zig-zags and the draws are loaded sideways from the fall line, or if the placements are on an overhanging wall, it may be more likely that the load will occur closer to the gate closing and further from the spine, in which case the biner can break well below its open-gate rating.

There is little or no solace for climbers to take from this, in the sense that there isn't much we can do to prevent the rare but by no means impossible scenarios such as the one in this case. Of course, gate-open failures can be prevented by using locking biners and/or doubling up biners. Modern light locking biners weigh no more than the standard biners of a few years ago, and make sense on particularly critical placements. In particular, it makes sense to use locking biners on the critical placement that protects the belay from a factor-2 fall, and on a protection piece at the start of a big runout. But no one is going to use them for a whole string of protection and/or aid placements, and so I suspect we will continue to hear about failures such as the present one---although, one fervently hopes, not very often.

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By Will S
From Joshua Tree
May 9, 2013
^^^
While I rarely use it, about 5 years ago following the example of a partner, I rigged a quickdraw with lightweight lockers on each end. Typically I'll use it on a pitch where the first piece is a bolt or fixed gear and it is a ways to the next piece, or if there is known long runnout between pieces. When you just cannot afford to have the last piece unclip or fail, it's nice to have that locking draw.

I might only use it 5 times a year, but in those 5 cases I'm real damn glad to have it.

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By Locker
From Yucca Valley, CA
May 9, 2013
...
Said it before, saying it again. I didn't get this nickname for no reason.

;-)

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By rgold
From Poughkeepsie, NY
May 9, 2013
The traverse out to the Yellow Ridge on the Dogstick Ridge link-up.  Photo by Myriam Bouchard
Speaking of testing protocols, there is at least one set of tests that suggest gate-closed strengths are "25 to 50 percent lower" then the rated values (now always obtained by static loading) when the load is dynamic rather than static. sciencedaily.com/releases/2009....

If this result is verified in further tests, the implication would be that gate-closed failures are well within the possible range of climbing dynamic loads.

Edit: Speaking again of testing protocols, the result above appears to be a false alarm; see theuiaa.org/upload_area/files/....

Interestingly, the article claims that gate flutter is an artifact of a testing system in which the falling weight rides on guide rails, and vibrations from the the weight, if their frequency happens to be close to the natural frequency of the gate, results in gate flutter. The point being that a honestly free-falling weight does not create such vibrations.

The article also claims that if a free-falling weight is used, the static test is actually more severe than the dynamic test, not less.

Note that even if it turns out that gate flutter does not occur "in the field," there is still the chance for "inertial gate opening" if the biner strikes something during the loading phase.

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By Matt N
From Santa Barbara, CA
May 9, 2013
OTL
In the era of 2000 fps high speed video cameras - perhaps some observations should be made. Would probably be cool to watch how draws and biners behave in various falls. Could be done at a sport crag fairly easily.

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By Taylor Bentz
May 13, 2013
My $0.02

I have noticed that when hanging on Mammut solid gate biners, my body weight alone (145lbs) is enough to make the gate hard to pull back, and it will not engage properly again while I am weighting the biner. This is the case only with Mammut solid gate aluminum biners in my experience, and applies to every single one I've ever done this on.

Given that I know this is a standard QC test (I think BD uses a 250lb post factory weighted-gate-opening/closing test on every one of its biners upon ex works), I am left to conclude that Mammut's standards for these biners' gate functionality while weighted is not as stringent as BD's.

Don't take my word for it, but maybe it would be prudent to hear from Mammut on this?

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By Optimistic
From New Paltz
May 14, 2013
Taylor Bentz wrote:
My $0.02 I have noticed that when hanging on Mammut solid gate biners, my body weight alone (145lbs) is enough to make the gate hard to pull back, and it will not engage properly again while I am weighting the biner. This is the case only with Mammut solid gate aluminum biners in my experience, and applies to every single one I've ever done this on. Given that I know this is a standard QC test (I think BD uses a 250lb post factory weighted-gate-opening/closing test on every one of its biners upon ex works), I am left to conclude that Mammut's standards for these biners' gate functionality while weighted is not as stringent as BD's. Don't take my word for it, but maybe it would be prudent to hear from Mammut on this?


Not sure if you saw the Mammut response in the supertopo link up thread. It does not specifically address the issue you observed, though. I think there is some contact info with Mammut reply, maybe you can email them and share their response?

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By jktinst
May 15, 2013
Taylor Bentz wrote:
My $0.02 I have noticed that when hanging on Mammut solid gate biners, my body weight alone (145lbs) is enough to make the gate hard to pull back...

I admit that the thought of this much flex on a biner is unnerving but wouldn’t that mean that there’s a lot less chance that a hit or rattling on the biner during a fall is less likely to flick the gate open ? Of course it'll depend on whether the hit happens before or after the loading.

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By Christiney
May 17, 2013
I would STILL use the gri-gri regardless of the impact force, but I wonder if a yates screamer had been in use, one of the pieces might have held.

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By Superclimber
May 17, 2013
Good God and holy fuken shit! Glad ya'll are ok.

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