Discussion Topic |
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Paul Martzen
Trad climber
Fresno
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Topic Author's Original Post - Feb 20, 2015 - 10:57am PT
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This photo was posted on a canyoneeering forum. I told the owner to contact Petzl. His brief account is:
Second to last rap on Monkeyface with lock gate (no misuse) and semi-soft start, very likely shifted on it's side (gate towards me not out); my rain coat may have covered my view of it the rest of the way, otherwise I would have noticed. Nearing the bottom and with the last step, a very loud low-base boom broke the carabiner. It was was off my harness and still attached to the rope. Found three pieces on forest floor but no pin.
My speculation is that his harness somehow opened the gate and loaded it sidways. The leverage broke the gate at the pin. But how you could open the gate and load it sideways while on rappel is very puzzling. Anyone know of studies of this sort of failure?
If there are insightful replies, I will copy them to this first post, so others don't have to search as much.
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Greg Barnes
climber
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Feb 20, 2015 - 11:09am PT
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Counterfeit biner?
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crunch
Social climber
CO
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Feb 20, 2015 - 11:30am PT
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Yikes!
I wonder if the pin was not finished properly and was working itself loose? If it were partway out then I could see there might be enough leverage to break the last bit of the gate like that.
Other scenario might be an existing hairline fracture in the aluminum? But then the pin would surely not be lost, it'd still be in its hole?
There may be more info that's not known or not presented here.
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fear
Ice climber
hartford, ct
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Feb 20, 2015 - 11:37am PT
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I've tortured cross-loaded locking biners like that with a truck just to see... I've only succeeded in breaking a few like that and those were under far more than body weight when they broke.
I see no way to do that with a rappel.
He did mention things were obscured under his jacket... Perhaps some kind of wild twisting going on. Did he ever post a picture of his usual rap setup?
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AlanDoak
Trad climber
Boulder, CO
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Feb 20, 2015 - 12:14pm PT
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Is this the type of biner where the sleeve screws down towards the gate hinge, or screws upwards to the nose of the biner?
If it locks at the gate hinge, could the contact point between the sleeve and biner somehow create a fulcrum near the fracture point, with the gate forming a lever with a lot of mechanical advantage?
Seems unlikely, I would expect deformation somewhere before catastrophic failure. I'm just brainstorming here.
But based upon the red indicator near the nose, it looks like it's the more conventional design where the sleeve screws upwards towards the nose.
I've seen videos of the testing rigs where they individually pull test every biner, and destructively test samples. YouTube "How carabiners are made". Anybody know what sort of QC goes into the gates and pins?
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AlanDoak
Trad climber
Boulder, CO
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Feb 20, 2015 - 12:25pm PT
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Was the gate locked at the time of failure? The exposed red indicator would suggest that it wasn't, but it might have been altered before the picture was taken.
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Mike Bolte
Trad climber
Planet Earth
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Feb 20, 2015 - 12:26pm PT
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this is one scary post
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Reeotch
climber
4 Corners Area
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Feb 20, 2015 - 12:30pm PT
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The only way I can see that happening is if the gate itself was loaded while it was open. This is totally possible if the biner is already being cross-loaded (with the belay loop across the gate). It would be even easier if it was a quicklock carabiner (I'm not sure from the photo, but I don't think it was.)
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Reilly
Mountain climber
The Other Monrovia- CA
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Feb 20, 2015 - 12:38pm PT
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One takeaway for me is where he mentions his jacket covering up his setup.
No matter how much clothing I wear I ALWAYS make sure I can see my setup -
all the time. Besides, if your clothing is covering your setup then it is
only a matter of time before it gets caught.
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Happiegrrrl2
Trad climber
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Feb 20, 2015 - 12:40pm PT
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So that biner says 6K with an open biner. How much force DOES a simple body weight rappel put on a piece? Of course way, way, lower than six, I'd think. Just wondering.
It would be interesting to find out if it was a counterfeit.... And as a reminder - don't buy yer frigging climbing gear from Joe Nobody on EBay selling mass amounts of brand new gear at below a bargain prices!
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thebravecowboy
climber
On this ride, I'm cptn; My pals call me Shackleton
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Feb 20, 2015 - 12:41pm PT
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why-o-why did I open this thread?
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Reeotch
climber
4 Corners Area
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Feb 20, 2015 - 12:54pm PT
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So that biner says 6K with an open biner
That is being loaded the long way. I'm saying he could have weighted the open gate, so the only support it had was the pin.
I bet there are many climbers who could break the open gate off a biner with their bare hands! (I'm gonna go try it)
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crunch
Social climber
CO
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Feb 20, 2015 - 01:11pm PT
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Great comments. Rapping, it would be almost impossible to cover up the rappel device. The device has to be high up above clothes just because it's what one is hanging from.
It appears to be a Petzl Attache. Burly carabiners.
I still think the 2 scenarios are:
a defective pin that was coming loose.
Or, if a grigri was involved, the grigri could have been pushed around to the hinge and thus put a lot of nasty torque on the gate, It can actually catch on the peened, mushroomed bit of the pin (just tried this with grigri and Petzl Attache). You'd have to be pretty inattentive to not see this happen.
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rgold
Trad climber
Poughkeepsie, NY
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Feb 20, 2015 - 01:21pm PT
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This type of danger has been known for a good fifteen years and has resulted in at least one fatality. The problem is that certain devices can, in some circumstances, get into a position (and there are at least two such positions) to lever open a locking carabiner gate, and no more than body weight is needed. One of the fatal configurations is more likely to happen if the locking biner is clipped through the harness tie-in points rather than the belay loop.
The documentation I know of refers to figure-eight rappel devices and is at http://theuiaa.org/upload_area/files/1/Karabiner_Breakings_when_using_a_Figure-of-eight.pdf. Pictures of two possibly bad configurations are included.
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Port
Trad climber
Norwalk, CT
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Feb 20, 2015 - 03:24pm PT
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Absolutely horrible if somehow these fake biners have made it into circulation.
Bravecowboy you abandoned your son
pick up the phone he wants to talk to you
your obviously posting online
grow a pair and call
Does the Supertopo drama ever stop?
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Gnome Ofthe Diabase
climber
Out Of Bed
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Feb 20, 2015 - 03:25pm PT
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Ouch to the search for the (notso) brave one
and as the happiest goyle said, >>>+1
that is as Clint and rgold point out not the 1st but it looks like all my newest lockers.
Gonna go and have a look,
I really can't say but it seems that the older Gri Gri's hole was prone to cross loading the petzel (or a fake??) in bad ways.
Every one has said it in so many ways,Yikes,
This is another reason that Tying in and creating redundancy with a waist loop (chack bag belt of webbing tied with a water knot and clipt to a back up (prussic,Klimbhiest)On long raps. with two 70 meter long skinny ropes is a good idea( if not a pain in the a.)
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Paul Martzen
Trad climber
Fresno
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Topic Author's Reply - Feb 20, 2015 - 03:46pm PT
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Thank you for the really excellent replies and especially for the links. I had not gone searching for such studies yet. I am in contact with the unfortunate yet very lucky fellow and will get more information about his set up. Prior to my writing to him, he assumed that he somehow put 7kN of force on the carabiner while rappelling. He had been making some comments that I did not take seriously until he posted the photo. Holy Crap!!!! I have been encouraging and interrogating him since.
I will forward the links to him and report further details here.
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Greg Barnes
climber
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Feb 20, 2015 - 04:27pm PT
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Ask him where exactly he bought the carabiner. If it's a random cheapo internet source, it'd be more likely to be a knock-off.
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LuckyPink
climber
the last bivy
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Feb 20, 2015 - 04:36pm PT
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the typical canyoneering belay device is a Petzl Pirana. the attachment end has a rubber stopper in it to prevent loss of the device and to hold it very firmly in place while in use. If the gate is caught there it could easily ratchet backwards and snap the gate. Thanks for the posts, especially rgold, we can count on you guys.
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LuckyPink
climber
the last bivy
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Feb 20, 2015 - 04:45pm PT
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hmm. I really like the attache and use a lot of them. bummer. I wouldn't know how to assess the pin on the ones I have except for being inordinately loose.
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k-man
Gym climber
SCruz
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Feb 20, 2015 - 04:48pm PT
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Well at least we know what broke the 'biner:
... a very loud low-base boom broke the carabiner.
I wonder if dogs could hear the boom?
But seriously, that is concerning. It looks like the 'biner has had some use, so it's hard to say what was the initial cause of the failure.
In the world of climbing we often depend on redundancy. But then there are the actions, like rappelling, where we depend on single pieces of equipment.
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scuffy b
climber
heading slowly NNW
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Feb 20, 2015 - 05:41pm PT
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In the world of climbing we often depend on redundancy. But then there are the actions, like rappelling, where we depend on single pieces of equipment.
It's awfully easy to use two carabiners while rappelling.
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Batrock
Trad climber
Burbank
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Feb 20, 2015 - 07:14pm PT
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The biner rwedgee posted has a different kN rating than the one that broke, did the ratings change or does anyone know if the fakes used the same specs?
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Wade Icey
Trad climber
www.alohashirtrescue.com
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Feb 20, 2015 - 07:37pm PT
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might just be the angle, but the pin hole looks elongated.
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drljefe
climber
El Presidio San Augustin del Tucson
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Feb 20, 2015 - 07:40pm PT
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You had me at
"canyoneering forum"
say no more.
;-)
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Flip Flop
Trad climber
Truckee, CA
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Feb 20, 2015 - 07:42pm PT
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Ahem.
Here we go again.
K-man writes In the world of climbing we often depend on redundancy. But then there are the actions, like rappelling, where we depend on single pieces of equipment.
PSA
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phylp
Trad climber
Upland, CA
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Feb 20, 2015 - 10:26pm PT
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Wayyyyy scary.
This OP has been a public service announcement.
Thanks!
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climbski2
Mountain climber
Anchorage AK, Reno NV
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Feb 21, 2015 - 08:23am PT
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I suppose the main thing to take from this is to check out any of the same Petzls to see if perhaps a bad run was made. If you have one check it. (how I'm not sure though?) bad pin? unusual play or action? We don't have metalurgical Xrays. Counterfeit or not will be hard to tell.
As always try to avoid operator error and gate loading.
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tradmanclimbs
Ice climber
Pomfert VT
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Feb 21, 2015 - 08:29am PT
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Fig eight or a gri can do that.
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rwedgee
Ice climber
CA
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Feb 21, 2015 - 08:33am PT
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Think of rapping from a fifi hook....it's doable but I wouldn't really want to.
I agree with Wade, the pin hole does look elongated. The pin had to come out before it broke as the ends are larger than pin diameter. If it didn't the pin would still be in one of the intact holes of the gate or the biner.
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Paul Martzen
Trad climber
Fresno
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Topic Author's Reply - Feb 21, 2015 - 09:01am PT
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Thanks for the continuing feedback.
Flip Flop, I have poo pooed the extension and prussic back up shown in your photo, but I might be coming around. Will start experimenting with that method immediately.
There is one difference is this case from the events reported in Rgold's link. In those reports, the Figure 8 twisted onto the gate and opened the gate or broke it off. The Figure 8 came free of the carabiner and the carabiner stayed on the harness or fell off. In the present event, the harness likely broke the gate because the carabiner stayed attached to the Figure 8.
Oh, the harness was a BD Alpine/ice harness and the rappel device was a Petzl Piranha as Lucky Pink guessed. I have asked the fellow to take a photo of how he thinks the set up was at the time of the accident.
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dhayan
climber
los angeles, ca
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Feb 21, 2015 - 10:14am PT
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As far as the screw gate coming unlocked, that has happened to me while rappelling before. I was cleaning gear under a roof and had moved horizontally while on rappel. When I looked down my locking carabiner gate was stuck partially open - scared the crap out of me! Apparently the screw gate had briefly rubbed on the rock but it was enough to open it completely. This was with the newer lighter version of the petzl attache, where the screw gate part protrudes out a little bit more than most other locking carabiners.
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JLP
Social climber
The internet
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Feb 21, 2015 - 11:27am PT
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The hole for the pin is enlarged, and the failure mode on the gate is consistent with this.
My speculation is that the gate was locked OPEN, or opened while unlocked, then busted off somewhere in the rappel.
Until I see more data, I'm rolling with "user retardation". Since it was under a coat when it happened (WHY?), we'll probably never know more.
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Clint Cummins
Trad climber
SF Bay area, CA
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Feb 21, 2015 - 12:42pm PT
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Petzl Piranha - a figure 8 type device.
Could exert considerable leverage on a biner.
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healyje
Trad climber
Portland, Oregon
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Feb 21, 2015 - 03:42pm PT
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I agree, the most likely scenario is the gate was either not locked or came unlocked, the gate opened and leveraged until it broke. The fact it was covered by a raincoat adds to that likelihood I would think.
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cornel
climber
Lake Tahoe, Nevada
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Mar 11, 2015 - 09:23am PT
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This is an important post..Yep this is operator error I bet. Screw lock was not completely closed. Raincoat obscuring vision coupled with a wiggling harness opened the gate completely creating the opportunity for the cross-load to blow up the biner. When a gate is loaded at an angle and completely open with rappel device resting on the gate, biner will fail at a relatively low load. This is the weakest point of any carabiner.
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Gnome Ofthe Diabase
climber
Out Of Bed
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Mar 11, 2015 - 11:21am PT
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`
In the picture, the device attached to the ' gold/yellow 'biener,is a 'Robot'.
A device that I have used for decades.
The circumstances that resulted in the "damage Under Body ..."Do Not Matter to me,
I use my gear carefully, but I want to feel One Hundred Percent confidence in the gear I use.
Especially when it is single locking 'bieners, that is to say no more single Gates,
between me 'n raven food & reincarnation.(when thats practical) still have to leading ect.
In the constant fight against complacency, I add redundancy when ever or where ever I can.
It turns out that I have six, one non anodized 1st gen that the screw sleeve, has been repurposed, and five gold, so to me I only retired one the others I will use in pairs only.
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AE
climber
Boulder, CO
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Mar 11, 2015 - 11:24am PT
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Several notes:
Another noticed the slight differences in the test rating stamp; it even looks a bit less professional than the example - just coincidental?
Also, those gate load test ratings appear to be with gate closed, making the low numbers even more alarming.
Do keep in mind tho' the major test loads we are familiar with relate to the breaking of the main 'biner; this technically did not fail, as only the gate portion was trashed. This of course would not be good if the belay/rappel system, or your harness, were the portions attached to that gate.
Modern 'biners have become more specialized, uber light, yet stronger in primary axes than good old SMC ovals of the 70s. Still, in 'biner braking systems I just can't trust the radically asymetrical and wire-gated thingies, mostly because they don't ever make maximal, planar contact with one another, especially when properly opposing the gates.
Even the gate lock itself creates problems when used in biner-only brake systems. The ever-expanding variety of locking mechanisms need to be carefully assessed for your particular use, as ropes under tension can do strange things like compress a button, rotate a collar, etc.
Last, always send failed equipment to the manufacturer if possible, as they are anxious to avert future accidents, whether from heat treatment batch problems, design flaws, or other causes. Speculation without analysis adds little to the resolution - for instance, since the gate latch was trashed, and the hinge area intact except for the odd pin loss, clearly the gate could not have been loaded when open, or else the latch portion would be entirely uninvolved. Think before you toss a random notion into the mixer.
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couchmaster
climber
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Mar 11, 2015 - 11:32am PT
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It's all just speculation until the breakee shows up and says what device he was using, how it was configured, and where he bought the carabiner.
I found it of interest that http://thecounterfeitreport.com/product/210/Attache-M35-SL.html doesn't list the differences. They are that similar. Most counterfeits have lists on the counterfeit report of the many ways you can spot the fakes ones. Not these.
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Gnome Ofthe Diabase
climber
Out Of Bed
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Mar 11, 2015 - 11:56am PT
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1strange devices often need short extension to help keep orientation /avoid cross loading ,ect.1a russian titanium 'bienr
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YYZ
climber
Alabama
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Mar 11, 2015 - 02:49pm PT
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Probably worse than a canyoneer... I'm a caver and frequent lurker on the taco. This thread caught my eye.
As has been stated, the tensile strength ratings for biners are across the x and y axis; with most mfg ratings including open/close gate. Cross loading, however, can result in forces great enough to break the gate screwlock mechanism and presumably the hinge-end (as in the OP pic).
This youtube by Brian Stoltz demonstates how easily a gate can be broken under much less kn force than mfg's ratings.
https://www.youtube.com/watch?v=5Fz0c1rC_88
Now I assume you all possess a 14" rack as your rapping device of choice. ;)
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Brian in SLC
Social climber
Salt Lake City, UT
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Mar 11, 2015 - 03:01pm PT
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Interesting.
The hole where the peened pin was does look elongated. Side load coulda busted the bottom off the gate?
Pirana...I've seen them slide down and get cockeyed (rescued a gal who'd done that over a 240 foot free air drop...exciting!).
I'd have to play with it, but, I wonder if the Pirana slid down, and, the action of the rope through the Pirana opened the gate...
Was the harness an old bod without a belay loop? Or, did the harness have a belay loop? Did he use a tether to extend his rappel point?
Was the Pirana attached to the rope still? Attached to the biner too?
I don't see much if any wear on the small end of the Attache. Which makes sense. The wear ought to all be on the big end especially with a Pirana.
Commonly used rappel device, maybe thee most popular especially in Europe. You can't afford to get stuck on a rope in moving water especially, hence no cord backups, etc. Important to be able to quickly get off rappel (folks have drowned). Specific tool for specific circumstances, for sure.
Scary. I've had pretty good luck with those biners and they're almost mandatory for use with a Pirana (or something very similar that will fit the snug through hole). Only issue I've seen is one that was locked shut that I had to beat on with a rock to get to unscrew.
Keep us posted, Paul. Thanks!
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Brian in SLC
Social climber
Salt Lake City, UT
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Mar 11, 2015 - 10:10pm PT
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Hmmm...this configuration could unscrew the gate...
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jstan
climber
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Mar 11, 2015 - 10:20pm PT
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YYZ's video shows cross loading after a twist. It is worth noting that video would have resulted in complete separation of the climber from the rope had the hinge end of the gate also broken. As was experienced in the OP.
My practice was to use a six/eight opposed biner chain clipped into my swami. I never used any of today's extra complicated devices.
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WBraun
climber
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Mar 11, 2015 - 10:27pm PT
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Flip the whole rig the other way if you're right handed.
Also the way you have it threaded with minimum friction for a single line rappel.
There's many many multiple ways to fuk up a rappel.
There's many many different ways to rig a rappel.
There needs to be absolute focus at all times from the rigging of the rappel to the end of the rappel to wherever one is headed.
Failure to maintain focused peripheral vision with being fully conscious of ones surrounding environment at all times during a rappel could lead to failure or even death.
It's not about knots in the end of a rope , but the entire whole rappelling business itself.
I've never used knots in the end of my rappel ropes to begin with because it can lead to further unseen problems.
But if someone likes knots at the end of their ropes then whatever, do whatever you want as far as that goes.
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Brian in SLC
Social climber
Salt Lake City, UT
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Mar 11, 2015 - 10:35pm PT
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Makes me think whatever harness he was using had a belay loop, and, the biner got crossloaded onto the gate. When it busted, they parted ways.
Really, if the Pirana/Attache was in a "normal" position, and loaded, even with the gate open (or missing), you wouldn't become disconnected from it.
Interesting to note the type of harness and belay loop orientation on the Petzl site (and the type in common use amongst some canyon folk). The belay loop on a "canyon" specific harness would orient the Attache so the gate would face straight up and not flat to the right or left. On a standard climbing harness, the belay loop is in the opposite plane which puts the Attache on its side with the gate either facing to the right or left. Should your brake hand bring rappel side of the rope over the side of the biner and against the gate...voila...
With a coat over his situation, makes me wonder if he fed the rope into the biner, and, locked it open (screwed the locking sleeve up with the gate on the inside of the nose). Unless you checked to make sure it was locked and didn't see that error, you'd never know even when you loaded up the rappel.
Looking at the photo of the broken bits, if he didn't mess with the gate, the locking sleeve is in a low enough position to be open.
I've notice minor axis loading on especially locking carabiners on my belay loop with a large locking sleeve. The newer Attache has a much smaller sleeve profile...
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Brian in SLC
Social climber
Salt Lake City, UT
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Mar 11, 2015 - 10:41pm PT
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"Flip the whole rig the other way if you're right handed."
Could do. That'd be safer with a belay loop on a standard climbing harness.
"Also the way you have it threaded with minimum friction for a single line rappel."
Yep. That's the way the cool canyon kids do it. Single line.
The Pirana is a neat rap device. Adjustable friction. Easy to lock off. Stays put on a biner. You can go off rappel whilst treading deep water and not drop it. Tends to favor folks who prefer rappelling with a dominant hand, as the friction pins and hooks on it are set up for one hand or the other.
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Clint Cummins
Trad climber
SF Bay area, CA
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Mar 11, 2015 - 11:01pm PT
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Failure to maintain focused peripheral vision with being fully conscious of ones surrounding environment at all times during a rappel could lead to failure or even death.
It's not about knots in the end of a rope , but the entire whole rappelling business itself. Absolutely true.
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jonnyrig
climber
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Mar 20, 2015 - 12:19pm PT
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Simple explanations often being most likely, looking at the pictures I would suspect that the carabiner rotated in such a manner as for the harness to be attached on the gate. If the rap device was attached at the larger end of the biner, and the gate managed to be forced open (inward), from either the gate being left unlocked or working its way unlocked during the rap, would it not then cause extreme leverage on the pin, causing the gate breakage shown in the OP, pin shear, and subsequent disconnect from the harness while still being attached to the rope?
Easy to play that scenario in your head, given the info provided. The hole in the hinge point of the biner appears elongated in the direction of an open gate, the gate itself is broken in a manner indicating sideways leverage while open, and lack of a pin would seem to be a result of forces experienced upon breakage of the gate. Seems pretty straight-forward to me. I doubt you could break a gate off with your hands, but under body weight while open suspect it would bend or pop right off without much effort.
At the bottom of a rap, while stopping and stepping down, changing the angle and the force applied...
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jonnyrig
climber
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Mar 20, 2015 - 01:06pm PT
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For your viewing pleasure... breaking a biner gate:
[Click to View YouTube Video]
Nothing but one good stomp with one foot. Nowhere near body weight. Attached via 550 paracord. Yes, it's an older carabiner. Yes, someone filed the locking portion of the nose off. That's why I chose it.... didn't want to sacrifice one of my good biners to the cause. Prior to this test, I saw nothing wrong with the biner, other than the removal of the nose lock, rendering it unfit for climbing usage. If you look at the following pictures, you may notice that the gate failed completely at the hinge, but the biner body at the hinge did not. It did crack, and it did elongate the pin hole. Additionally, both ears of the gate failed and the pin remained in place. I would encourage anyone with a similar crab to the OP to try the same experiment and post up results.
This has been a nonscientific test. Now back to your regularly scheduled programming.
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HighTraverse
Trad climber
Bay Area
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Mar 20, 2015 - 01:24pm PT
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Way back on page 1
The only way I can see that happening is if the gate itself was loaded while it was open. Or not fully screwed down.
What Reilly said:
One takeaway for me is where he mentions his jacket covering up his setup.
No matter how much clothing I wear I ALWAYS make sure I can see my setup -
all the time. Besides, if your clothing is covering your setup then it is
only a matter of time before it gets caught. If I can't see all of my belay or rappel rig I STOP (even mid rapp) and clear it. And double check that the gates are locked.
And Werner:
I've never used knots in the end of my rappel ropes to begin with because it can lead to further unseen problems. Indeed. I make the knot/no knot decision depending on the circumstances of each rappel AND with the specific assent of my partner. We both need to know how it's been set up. If I don't want a knot and he does, we do the knot.
But knotting the ends is a topic for another day. A lot of different safety considerations there.
I've never used a Piranha so I'm reaching a bit here.
It looks to me in Clint's pic of a rigged Pirahna that in some orientations the brake hand end of the rope can move across the 'biner screw. In the orientation shown, that would tend to tighten the screw. However, if the Pirahna is turned over right to left, the rope will be sliding across the screw in the direction to loosen it.
Note that the screw/unscrew direction reverses between belaying and rappelling.
A second point: the width of the Piranha's upper loop and the curved tang on the right in the pic provides a large leverage if the Piranha is rotated against the biner gate.
I'll let someone who has the dimensions of the Piranha and Attache work out the moments. My gut feeling is 1KN of cross force could easily be applied to the biner gate. Especially if shock loaded (think bouncing rappel)
And point 3: see the ATC in FlipFlop's photo of his redundant rig. I've always preferred a belay device with a "soft" attachment like the ATC. An idea I believe first introduced in the Lowe Tubular (which I still have somewhere in my antiques bin). It would be nearly impossible for this design to cross load the locking 'biner with significant force.
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jonnyrig
climber
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Mar 24, 2015 - 08:55am PT
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Nothing? Nobody wants to try a piece of paracord on the gate of a biner like the OP similar to my nonscientific video?
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| Messages 1 - 57 of total 57 in this topic |
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SuperTopo on the Web
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ATC?
Let us know!