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alpnclmbr1
Jun 11, 2004, 1:01 AM
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This is complete speculation based on disregarding the eyewitness reports and seeing what could possibly of happened from a theoretical viewpoint.
A piece of debris enters the grigri and tears the sheath.
In reaction the belayer (and friend?) Grab the brake side of the rope and pull up. This seems like a reasonable response to seeing the sheath shredding.
This turns the grigri 90 degrees to the fall line, lever side down.
Note 1: Assume that they pulled just hard enough to balance the load between the anchor and their pull on the rope, if they continued pulling it would have shifted orientation again
Note 2: Assume that at some point they pulled hard enough to pull eleven inches of rope back through the device, to account for the eleven inches between the core cut and the sheath damage.
The cam is still engaged with the weight of the climber. They continue pulling until the device approaches 180 degrees from the original orientation.
At some point in this process the rope (climber’s side) coming out of the grgri is going slide over the bugle in the cam where the plastic lever pivot point is.
When the cam is in the position it would be possible for a even an undamaged rope (climbers side) to slip behind the cam and be exposed to the sharp edge on the bottom of the cam which could easily cut the core.
This seems so plausible that it is scary. Someone shoot holes in my theory.
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jeffhasse
Jun 11, 2004, 5:02 AM
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Thanks for your comments. I agree that one of the main lessons that can be learned from this accident (for climbers, anyway) is that debris can enter a GriGri lying on the ground, which can then damage your rope.
I also agree that the belay system set-up in this type of situation (top-rope, belayer above the climber) warrants further scrutiny.
In reply to: Given the same situation, it's not uncommon (I've done this at sea-cliffs) to stand at the edge, attaching oneself and one's belay device to the anchor (the belay device could also be attached to the harness).
At least one climber (a climbing instructor) told me that he typically belays at this crag while hanging over the edge with the belay device oriented vertically. I believe he does this at least in part to be better able to coach his students up the routes. But this seems to be awkward, especially as the climber first climbs onto the belay system and when he or she tops out.
I just reviewed the few pre-accident pictures that I have from on top of the cliff and I noted that there was at least one other belay system rigged in a similar manner (belay device near the edge, attached to an anchor system, and lying on a pad in a horizontal orientation). In this case, the device was a belay plate. Given that this appears to be the most “convenient” way to belay under these circumstances, I am wondering if this is a common climbing practice? Given that at least one other person reported a similar experience with sheath damage from debris lodged in a belay device (www.rockclimbing.com/forums/viewtopic.php?t=59907&postdays=0&postorder=asc&topic_view=&start=0), should we be actively discouraging any belay system that forces the belay device to be in contact with a horizontal surface?
Note that I am neither advocating nor criticizing any of these approaches; I am just asking the questions to try to gain a consensus from the climbing community.
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cracklover
Jun 11, 2004, 2:10 PM
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In reply to: Thanks for your comments. I agree that one of the main lessons that can be learned from this accident (for climbers, anyway) is that debris can enter a GriGri lying on the ground, which can then damage your rope.
Thanks, yes.
In reply to: I also agree that the belay system set-up in this type of situation (top-rope, belayer above the climber) warrants further scrutiny. In reply to: Given the same situation, it's not uncommon (I've done this at sea-cliffs) to stand at the edge, attaching oneself and one's belay device to the anchor (the belay device could also be attached to the harness). From this description, it appears that in a fall, the belayer’s legs support a large portion of the climber’s weight. Not a big deal in top-rope falls (if there is not a huge weight differential), but if the climber is hang-dogging a lot, this system could get pretty tiring.
Yes, when the belay device is on your harness, the belayer takes all of the weight of the climber when the climber takes TR falls. For most situations in which the weight difference is not great, and/or the climber is not likely to fall more than a few times, this is not a problem. It sounds like the climbs these folks did all were not too difficult for them, but I don't know their relative weights. Note, though, that when the belayer is standing, and the belay is either re-directed through the anchor, or is directly off the anchor, a substantial amount of the force (in cases of numerous falls or long hangs) is transfered to the anchor.
In reply to: At least one climber (a climbing instructor) told me that he typically belays at this crag while hanging over the edge with the belay device oriented vertically. I believe he does this at least in part to be better able to coach his students up the routes. But this seems to be awkward, especially as the climber first climbs onto the belay system and when he or she tops out.
I don't much like having the belay device below me, as it's hard to work with the rope, but for cases where the climber is likely to fall and hang a lot, this is probably the best possible position (especially as taking in rope quickly won't be a necessity).
In reply to: I just reviewed the few pre-accident pictures that I have from on top of the cliff and I noted that there was at least one other belay system rigged in a similar manner (belay device near the edge, attached to an anchor system, and lying on a pad in a horizontal orientation). In this case, the device was a belay plate. Given that this appears to be the most “convenient” way to belay under these circumstances, I am wondering if this is a common climbing practice?
Never done it, nor seen it done. But I've only been climbing five years.
In reply to: Note that I am neither advocating nor criticizing any of these approaches; I am just asking the questions to try to gain a consensus from the climbing community.
Good question!
GO
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jeffhasse
Jun 11, 2004, 2:57 PM
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Just to clarify this belay set-up:
In reply to: At least one climber (a climbing instructor) told me that he typically belays at this crag while hanging over the edge with the belay device oriented vertically. I believe he does this at least in part to be better able to coach his students up the routes. But this seems to be awkward, especially as the climber first climbs onto the belay system and when he or she tops out. I don't much like having the belay device below me, as it's hard to work with the rope, but for cases where the climber is likely to fall and hang a lot, this is probably the best possible position (especially as taking in rope quickly won't be a necessity).
Here, both the belayer and the belay device are hanging over the edge of the cliff on separate anchors, so the device can be positioned at about head level and oriented vertically (as seen in the Petzl Technical Notice). This is similar to a common set-up for belaying the second on multi-pitch climbs. Hope this makes it more clear...
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cracklover
Jun 11, 2004, 3:45 PM
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In reply to: Just to clarify this belay set-up: In reply to: At least one climber (a climbing instructor) told me that he typically belays at this crag while hanging over the edge with the belay device oriented vertically. I believe he does this at least in part to be better able to coach his students up the routes. But this seems to be awkward, especially as the climber first climbs onto the belay system and when he or she tops out. I don't much like having the belay device below me, as it's hard to work with the rope, but for cases where the climber is likely to fall and hang a lot, this is probably the best possible position (especially as taking in rope quickly won't be a necessity). Here, both the belayer and the belay device are hanging over the edge of the cliff on separate anchors, so the device can be positioned at about head level and oriented vertically (as seen in the Petzl Technical Notice). This is similar to a common set-up for belaying the second on multi-pitch climbs. Hope this makes it more clear...
Yes, thanks. Obviously that's an excellent setup, especially if there is a ledge below the edge of the cliff. If there's no ledge at all, a hanging belay with a slow climber can get pretty tiresome.
GO
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alpnclmbr1
Jun 11, 2004, 4:22 PM
Post #106 of 118
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In reply to: In reply to: Just to clarify this belay set-up: In reply to: At least one climber (a climbing instructor) told me that he typically belays at this crag while hanging over the edge with the belay device oriented vertically. I believe he does this at least in part to be better able to coach his students up the routes. But this seems to be awkward, especially as the climber first climbs onto the belay system and when he or she tops out. I don't much like having the belay device below me, as it's hard to work with the rope, but for cases where the climber is likely to fall and hang a lot, this is probably the best possible position (especially as taking in rope quickly won't be a necessity). Here, both the belayer and the belay device are hanging over the edge of the cliff on separate anchors, so the device can be positioned at about head level and oriented vertically (as seen in the Petzl Technical Notice). This is similar to a common set-up for belaying the second on multi-pitch climbs. Hope this makes it more clear... Yes, thanks. Obviously that's an excellent setup, especially if there is a ledge below the edge of the cliff. If there's no ledge at all, a hanging belay with a slow climber can get pretty tiresome.
This is nuts.
In order for this to be like the petzl suggestion you would have to set up a simulated hanging belay below the edge. Maybe one in a hundred routes would have a ledge in the perfect spot below the edge on a top down crag to make this feasible.
Having the belay device and the belayer on separate anchors with a long extension between the anchors and the belayer/device is an unsafe practice where it is possible for the belayer to lose control of the belay device.
In this set up the climber would need a separate belay to get onto the system. And you would have to rearrange things in order for the climber to top out. wtf
Now you have me wondering. How long have you been climbing, Jeff?
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pneumoped
Jun 11, 2004, 5:02 PM
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The diagram you provided for the Bachman autoblock shows it on a single rope. Can it safely be used on a double rope? My intuition tells me that it might not work as well on a double rope? However, I have no experience with this knot.
Also, have there been any tests that might suggest one of the various autoblock knots you presented in the previous message were better than any others?
Thanks,
pneumoped
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jt512
Jun 11, 2004, 5:31 PM
Post #108 of 118
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In reply to: I also agree that the belay system set-up in this type of situation (top-rope, belayer above the climber) warrants further scrutiny.
As alpnclmbr1 mentioned, having the belay device on an anchor below you is awkard and non-standard. If the belay device is on an anchor, standard practice is to try to position it where it is in easy reach, say chest-level.
In reply to: In reply to: Given the same situation, it's not uncommon (I've done this at sea-cliffs) to stand at the edge, attaching oneself and one's belay device to the anchor (the belay device could also be attached to the harness). From this description, it appears that in a fall, the belayer's legs support a large portion of the climber's weight.
If the belay device is on the harness, usually the belayer would redirect the climber's side of the rope through the anchor. Having to hold your second's weight directly on your harness -- well -- sucks.
In reply to: I just reviewed the few pre-accident pictures that I have from on top of the cliff and I noted that there was at least one other belay system rigged in a similar manner (belay device near the edge, attached to an anchor system, and lying on a pad in a horizontal orientation).
I have never heard of belaying with the belay device on the ground, and I cannot imagine how doing so could be safe. With a grigri, you have the risk of getting debris in the device. While prior to reading this accident report, I would not have imagined that this could cut a rope, debris in the device is known to be able to prevent the device from locking, which is almost as bad. Secondly, it is dangerous to have the grigri against any surface, vertical or horizontal, since in a fall, the camming mechanism could be pressed against the surface, preventing it from locking. With an ATC, I would think that the ground would prevent the rope from running through the device at the best braking angle. Regardless of belay device, if the device is sitting on a ledge, then the rope has to run over the edge, which is hard on the rope, and possibly dangerous. Sure, you can pad the edge, or you can just set the belay up properly in the first place.
-Jay
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sandstone
Jun 11, 2004, 5:59 PM
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alpnclmbr1 wrote:
In reply to: This is complete speculation ... When the cam is in the position it would be possible for a even an undamaged rope (climbers side) to slip behind the cam and be exposed to the sharp edge on the bottom of the cam which could easily cut the core. This seems so plausible that it is scary. Someone shoot holes in my theory.
Interesting thought experiment.
That scary edge on the Gri-Gri is a thin blade of metal, but it is definately not sharpened like the business side of a knife -- it's more like the blunted top side of a thick knife blade. Of course with enough force, even a blunt stress concentrator can cause a failure, but I have to wonder if there's enough force in this scenario.
Part of the hanging climbers weight will be absorbed by the rope running over the padded cliff edge, so let's say his load contribution is 120 lbs. Let's say the belayers add another peak load of 300lbs by pulling on the rope on the other side of the Gri-Gri (that may be very generous on their contribution, and the rise time of their force is going to be relatively long because their pull is probably not going to be perfectly synchronized). I speculate that there's just not enough force to cut the entire core bundle over that blunted edge.
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alpnclmbr1
Jun 11, 2004, 6:11 PM
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Just to continue the speculation. They said the climber was trying to grab onto the rock. This has the potential of increasing the forces.
One more factor. If you have a grigri handy, look at the scissoring action if the cam releases with the rope in that position.
I am pretty sure I could cut a rope core in that scenario.
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sandstone
Jun 11, 2004, 6:26 PM
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In reply to: The diagram you provided for the Bachman autoblock shows it on a single rope. Can it safely be used on a double rope? My intuition tells me that it might not work as well on a double rope? However, I have no experience with this knot.
Just a couple of weeks ago me and my partner used bachman knots to ascend a (wet) doubled rope. They worked fine for us.
The scenario was that we had climbed a short pitch to a belay just below an offwidth roof crack. It started raining, and dripping down through the crack pretty bad, so we went down to have lunch. After the rain shower we went back up the doubled rope with bachman knots made with runners (we didn't have ascenders or prusik slings with us).
I like the bachman because you can make it from gear you most probably already have on you, and it's easy to grab and move up.
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jeffhasse
Jun 12, 2004, 1:15 AM
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Relax, good man (bad British accent)... :? I am simply trying to clarify potentially safe and unsafe climbing practices in this unique set of climbing circumstances. I say once again: In reply to: Note that I am neither advocating nor criticizing any of these approaches...
It is very tough to have a discussion about the subtleties of various rigging practices in this kind of forum where we cannot demonstrate, draw pictures, gesture with our hands, etc. Frankly, trying to visualize all the details of a safety system or an event through the written word alone sucks. Yet it is worth making the attempt.
I entered this forum because it was clear to me that, in spite of the length of the accident report, people were still making dubious assumptions based on incomplete or imprecise information. I thought it would be helpful to hear from the “horse’s” mouth. If I haven’t been clear please ask me to clarify, I will do my best to do so. If the moderators of this forum were to give me a little assistance, I would be happy to post a few photos to help the process (I’m still a newbie poster).
I agree with you that there are problems with the belay set-up described above; that is why I brought it up. I believe you started to describe another: In reply to: Having the belay device and the belayer on separate anchors with a long extension between the anchors and the belayer/device is an unsafe practice where it is possible for the belayer to lose control of the belay device.
Could you expound some on that danger for the 90% of the climbers out there that do not consider themselves experts?
If you must know (who really cares?), I’m an “old fart” (early 40’s) and have been climbing about 30 years. In the interest of full disclosure, I do not consider myself an “expert” or a climbing guru. I’ve been doing it long enough to be relatively safe and not often enough to be really good. I am certainly not among the climbing elite (you won’t ever find me featured in Climbing magazine). Yet I am committed enough to it to try to climb better and—more importantly—safer. So here I am… It may be useful to remember that, if you climb long enough, you wind up learning and unlearning “safe” climbing practices several times over (I started with hip belays for god’s sake…). In addition, it has been my experience that one region’s “safe” climbing practices is another’s; “This is nuts.” If climbing practices were uniform throughout the world, we wouldn’t need these forums. (BTW, the climbing instructor who told me about his practice has been climbing a lot longer than me…)
Cordially Yours,
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alpnclmbr1
Jun 12, 2004, 1:47 AM
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Jeff,
I didn’t mean to get all uppity, but I have seen a large variation in the skill levels associated with SAR personal. It is a lot better then it use to be. Your evaluation of the anchor set up seemed strange in light of what may very well be a regional bias on my part. These scenarios still seem very unsafe to me, in light of having learned in the west.
Someone that proclaims to be an expert usually isn’t. That view has been highly reinforced by spending time on this site. I am far from being an expert, but I might qualify as being experienced.
RE: your question
On multi pitch routes one of the reasons you do not belay a leader directly off the anchor is because in a fall the belay device could be pulled away from the belayer. (Assuming separate anchors, in a fall the belay device would be yanked upwards relative to the belayer.)
In terms of a TR set up it is not so bad, but it can still contribute to a loss of control by the belayer. My suggestion would be to connect the two anchors in some way in order to prevent the possibility of the belay device being separated from the belayer.
Regards,
Dan
ps.I am sure that I have a number of practices that some people would object to.
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alpnclmbr1
Jun 12, 2004, 1:54 AM
Post #114 of 118
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One more point.
I haven't seen or heard of these anchor configurations in any books, through the amga, through the uiaa. I can't recall ever having seen this online either for that matter.
Has anyone?
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jeffhasse
Jun 12, 2004, 4:06 AM
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Dan,
Thanks for that clarification, I figured that was where you were going...
RE: Your question
I can't recall reading anything about anchors in these circumstances either (although I haven't had a chance to dig out my books yet), that is why I think it is worth discussing. Hope others have comments and suggestions.
I agree with you that there is a wide range of skill levels associated with SAR/Technical Rescue people. I've seen firefighters consider themselves "trained' after completing a 12 hour workshop. The situation is getting better over time though. Standards, they be a changin'...
Differing technical rescue skill levels are not all that bad, as long as you know your strengths and weaknesses. I have a friend who is a very competent technical rescue guy who won't get near rock, it gives him the willies. Yet, he has no problem working on high transmission lines with a gazillion volts of electicity around him. Yikes :shock:
Anyway, have a good weekend, I will probably not be around to answer many questions about the accident or report for the next four days. Gotta earn a living :cry:
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skidawg
Jan 15, 2005, 10:26 PM
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I am sorry also to hear of your loss.
I overheard a person working at the local gym talk about a few of his buddies and a similar event. They were using the grigri as an anchor and some dirt got into the device, got wedged in the cam, and completely cut the rope...it just smashed the dirt/rock particles into the rope with enough force to cut it....at least this is what I gathered...again I overheard it, so I don't want to say that I'm my facts are completely sound.
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moondog
Jan 17, 2005, 3:02 PM
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In reply to: I overheard a person working at the local gym talk about a few of his buddies and a similar event.
The person you overheard was probably either recounting a distorted version of the event that started this thread, or making up a story based on same. Think you can find out more?
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jambalya
Feb 23, 2008, 10:15 PM
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I'm going to make this brief because I don't want to start something big.
I'm the brother of the deceased that this topic is about. Let me say that I'm humbled by the discussion here, because I don't know much about climbing. All I know is that if and when I do go climbing, I will only do it with my good friend Chris (you know the guy who came up with this discussion). I trust him completely.
Thank you Jeff for all of your input here. It seems to have been very helpful.
If there is to be anymore discussion on this topic, I request that we stay away from literary critic (i.e.: the title of the thread), and bashing others ("sandstone"). Until Jeff got on here it was pretty sad.
I hope that there is still something to be learned from this tragedy.
John
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