Accident Report - Rigging Failure During a Rappel

[bjp]

With a simple half-twist, you can make a LOCKING FIGURE-8-BLOCK, which seems to have all the bene's of the non-locking version, plus the benefit that it locks, no matter what the cord size.

Thanks! I think I'd go so far as to say that this extra half-twist is "right" and the way I (and a number of other people, apparently) have been doing it is not right. I haven't tried the locking version myself yet, but I see what's going on by looking at your picture. I'll try to color that picture a little later so everyone else can see how it works a little more easily. I'm going to remove my video because I don't want to perpetuate the non-locking way of rigging an eight block; I'll edit my previous post to include a note of what it used to contain.

[ratagonia]

Yeah, Tom, that half twist make a big difference to me.

I'd be good with whatever contingency rig folks want to use, munter/mule, stone, figure eight... I wouldn't be overly psyched to dive onto a jester rig with a 8mm canyon pro rope, though, unless one side is tied off.

Cheers!

Seems like, using the Jester rigging there is a touchy balance. The friction has to be low enough so that once you have changed to a lower, the lower works. Which means other versions that lock become a problem, because they then do not convert easily to a lower. Or you can lock off one side, but then you do not have a dual-line system, so use a different contingency system.

Very hard to set up the dual-line easily convert to lower system. Hard to say why one would want that - I don't. In a true Class C, seems unlikely to use the dual-lines (but could). Having another person on the other rope would delay applying the contingency to an under-water canyoneer who needs to be lowered.

If I really wanted dual lines in a Class C situation, I think I would set up two separate systems, with contingency.

But why are people setting up contingency anchors in Class A canyons? Perhaps I am floggin this horse again and again and again, but... seems like setting up dual lines using a Stone, and having your conversion to a lower from a Stone practiced and polished is going to be, long term, a better system than setting up a dual-line pseudo-contingency system like the Jester, that has some problems with small-diameter ropes.

Tom

[Deathcricket]

Seems like, using the Jester rigging there is a touchy balance. The friction has to be low enough so that once you have changed to a lower, the lower works. Which means other versions that lock become a problem, because they then do not convert easily to a lower. Or you can lock off one side, but then you do not have a dual-line system, so use a different contingency system.

Very hard to set up the dual-line easily convert to lower system. Hard to say why one would want that - I don't. In a true Class C, seems unlikely to use the dual-lines (but could). Having another person on the other rope would delay applying the contingency to an under-water canyoneer who needs to be lowered.

If I really wanted dual lines in a Class C situation, I think I would set up two separate systems, with contingency.

But why are people setting up contingency anchors in Class A canyons? Perhaps I am floggin this horse again and again and again, but... seems like setting up dual lines using a Stone, and having your conversion to a lower from a Stone practiced and polished is going to be, long term, a better system than setting up a dual-line pseudo-contingency system like the Jester, that has some problems with small-diameter ropes.

Tom

Agreed. Also having something simple you can visually inspect and know (at a glance) if it's either right or wrong is mandatory IMO. This whole "maybe with this size rope, maybe not with this size rope" argument when your life is on the line is pretty lame IMO. Just to save a minute "maybe" in a class C canyon? Yeah I'll pass..... Stone knot all the way.

[Scott P]

I thought I knew how to rappel, but after reading this thread, I've come to the conclusion that I don't know jack.

[ratagonia]

I thought I knew how to rappel, but after reading this thread, I've come to the conclusion that I don't know jack.

Careful of the Jack guy. he talks big, but he is a danger to himself and others....

Tom

[bjp]

With a simple half-twist, you can make a LOCKING FIGURE-8-BLOCK, which seems to have all the bene's of the non-locking version, plus the benefit that it locks, no matter what the cord size.

Here's a colored version showing the high-tension strand (yellow-green) pinning the low-tension strand (blue) against the figure 8 and locking the block; it seems like this is the version everyone should use.

[bjp]

This whole "maybe with this size rope, maybe not with this size rope" argument when your life is on the line is pretty lame IMO.

You have that argument every single time you select the rigging style for your rappel device. Having it one more time for the block may or may not be appropriate depending on the circumstances.

Just to save a minute "maybe" in a class C canyon? Yeah I'll pass..... Stone knot all the way.

In a class C canyon, the rappeller would presumably be unable to breathe for that minute. Contingency riggings are good ideas in C canyons, even if not the Jester.

[Deathcricket]

You have that argument every single time you select the rigging style for your rappel device. Having it one more time for the block may or may not be appropriate depending on the circumstances.

I do agree with you, yes. Nothing wrong with what you said. But if you start a rap and your device needs more friction, there are many ways to correct the situation. If you start a rap using the joke(r) and it starts to slip, you simply splat on the ground. IMO this is a huge distinction and why one side should always be tied off. *shrug*

[Deathcricket]

[QUOTE=ag23;505440][B]Hello,
[FONT=Arial]I

[hank moon]

Hey thanks again for bringing this to the community. I think you did a great service, and it takes courage to come forward when the $#!t hits the fan on your shift. And not only that but you did a followup test and posted a picture of your exact rigging before the accident. This is no small thing you did! Great thread I think.

X2, Andre - thank you for braving the poonami - great info and glad your friend wasn't seriously injured - how is he, btw?

[Iceaxe]

X3

Thanks Andre

Sent using Tapatalk

[ghawk]

x4

what they said

[moab mark]

Went out and played with this in my garage. I can see why the Card Shark likes this. It is easy to set up and doing everything I could from swinging to jumping up and down I could not make it slip. Obviously it will because someone is wearing a cast but I could not get it to budge one inch. I also set it up using my ATS and seems to work the same. If you had the first guy down rappel double and then belay the lines I would have no concern using it. I shot a video of how I think you make it release but I cannot get it to load. Without removing the unloaded strand from the biner I could not get it to slide. Once you remove unloaded strand you can lower. I am using an 8.3 canyon fire rope. How do I get a video from my I phone which is downloaded onto my computer upload here?

Mark
Here is the video not the best but gives an idea of how the jester is suppose to be released.

http://www.youtube.com/watch?v=n5l8LJ9RM2g&feature=plcp

I just went over to the ACA site and looked at a picture that was hard to understand but it looks like you are suppose to feed the non loaded strand without removing it from the biner? I tried that with my test and could not make it slipped that way. So at this point just take the video as entertainment only, have no clue how you are suppose to lower a victim.

Mark

[Brian in SLC]

X5.

Not a lot of threads get me to the hangboard to practise rigging configurations. Good fodder.

Thanks!

[Iceaxe]

How do I get a video from my I phone which is downloaded onto my computer upload here?

I post them to YouTube, because that is usually the easiest and many phones are only one click to upload straight to YouTube. Once they are on YouTube I post the link on Bogley.

I'm sure there are numerous other ways to skin this cat.

[deagol]

Which ascending system are you using? Stop-n-Go or Plaquette (autoblock).

....

I used it in Plaquette mode. I asked the question of how to rig it a year or two ago (??) on the ACA website (the master Totem thread) and followed your example. I think it worked great at first, but as the Totem wore-in a bit, it slipped. I really like the versatility and it still works great with my 9 MM rope. Also, for the record, I don't use it often at all in ascending (plaquette) mode- Just messing around with it in practice sessions in case I needed it for real out in the field.

[marlowequart]

It sounds like your friend was very lucky with the ledge and quick sar response. One question i had, is the jester supposed to work just as good on say 30' of rope as 100'? It seems like the weight of the rope could add friction to the system too.

Also, thinking that since something has worked successfully many times in the past then it will continue to work successfully in the future seems risky to me. Every system has some failure mode. Its a balance of risk to reward.

[canyoncaver]

But why are people setting up contingency anchors in Class A canyons? Perhaps I am floggin this horse again and again and again, but... seems like setting up dual lines using a Stone, and having your conversion to a lower from a Stone practiced and polished is going to be, long term, a better system than setting up a dual-line pseudo-contingency system like the Jester, that has some problems with small-diameter ropes.

OK, I'll bite. Sometimes in class A and B canyons, you can't see the bottom of the rappel. In this situation, we often use a contingency 8 to lower the first person down in order to set rope length. Or, if we "think" we have the rope on the bottom, but aren't quite sure, we will go ahead and rig the 8 block so that the first person doesn't have to ascend back up when the rope is actually not on the ground.

Overall, we use biner blocks as the go-to, but the 8 does come in handy from time to time. Unless the pull is completely clean, we even change out the 8 to a biner block for the pull. I have found that 8 blocks dragged over sandstone = mucho sheath damage. Biner blocks do not seem to share this issue.

While I was shown the Stone and Joker in canyoneering merit badge school, I have never seen the need to rig either one. Having two ropes hanging down the pitch is not usually something we find desirable. But, it depends on everyone's personal situation. We don't do any guiding, and everyone we canyon with is capable of rigging their descender in 7 seconds or less, so the advantages of dual line systems don't really add up to much for us.

[moab mark]

OK, I'll bite. Sometimes in class A and B canyons, you can't see the bottom of the rappel. In this situation, we often use a contingency 8 to lower the first person down in order to set rope length. Or, if we "think" we have the rope on the bottom, but aren't quite sure, we will go ahead and rig the 8 block so that the first person doesn't have to ascend back up when the rope is actually not on the ground.

Overall, we use biner blocks as the go-to, but the 8 does come in handy from time to time. Unless the pull is completely clean, we even change out the 8 to a biner block for the pull. I have found that 8 blocks dragged over sandstone = mucho sheath damage. Biner blocks do not seem to share this issue.

While I was shown the Stone and Joker in canyoneering merit badge school, I have never seen the need to rig either one. Having two ropes hanging down the pitch is not usually something we find desirable. But, it depends on everyone's personal situation. We don't do any guiding, and everyone we canyon with is capable of rigging their descender in 7 seconds or less, so the advantages of dual line systems don't really add up to much for us.

Double strands help move large groups thru a canyon, especially Youth Groups. If the anchor is bomber you can have two Youth rappeling at the same time. If one Youth is extremely slow several other Youth may descend the other strand while the other Youth is still on Rappel. When the group is big and the anchor can support it, it is the only way to fly.

If your group is experienced and you cannot see the bottom just drop the bag and biner block it. Adjust for pull at the end.
Mark

[hank moon]

except...block before drop