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Pros and cons of simul-rappelling

patto · · Unknown Hometown · Joined Jul 2012 · Points: 25

Don't put blind faith in autoblocks especially if you don't extend it.  IMO if you are going to use an autoblock, do it properly and extend your rapell device.


L Kap · · Boulder, CO · Joined Apr 2014 · Points: 95
patto wrote: Don't put blind faith in autoblocks especially if you don't extend it.  IMO if you are going to use an autoblock, do it properly and extend your rapell device.



Wow, scary. Thanks for sharing.

It's hard to see what his set-up is, but at 1:06 you can see he was doing a single line rappel and did not use an extra carabiner for friction. You get a blurry glimpse of his friction hitch at 1:26 - looks like just a couple of wraps with a thin cord, hitched to his leg loop. Seems like an insufficient number of wraps, especially on a wet rope. These seem like important factors in the fall.

Unclear if rappelling directly off the belay loop had anything to do with it. Is there more info besides the video?

patto · · Unknown Hometown · Joined Jul 2012 · Points: 25

The discussion is linked in the video.   You can read it here:

http://www.bogley.com/forum/showthread.php?62220-Rap-accident-in-Rubio-Canyon-60-fall

Nick Goldsmith · · Pomfret VT · Joined Aug 2009 · Points: 440

biggest thing with auto block is to test it and use it a lot and understand what it will and will not do.  A loose autoblock that slides easily down the rope will not work to stop you on the bottom 1/2 of your rappel.. it has to be tight enough to be a PINTA at the top of the rappel to actually work at the bottom of the rappel. 

Carolina · · Front Range NC · Joined Nov 2010 · Points: 60
patto wrote: The discussion is linked in the video.   You can read it here:

http://www.bogley.com/forum/showthread.php?62220-Rap-accident-in-Rubio-Canyon-60-fall

Looked like he completely let go of the brake strand.   Several accidents over the years with climbers using auto-blocks, enough that I question the reliability in less then perfect setups.  Like not extending, providing enough raps, spacing between devices and climbers failure to let go of auto lock in a fall.  


Question: does anyone know if autoblock performs better on a double line rap or single line? 
Tim Stich · · Colorado Springs, Colorado · Joined Jan 2001 · Points: 1,482
Carolina wrote:


Question: does anyone know if autoblock performs better on a double line rap or single line? 

I'm pretty sure neither will engage if your rappel gets out of control. They are only useful if you need a hands free stop. rgold might have some elaboration on this, but that's what I understood.

As for the video, why rappel on a single strand when you have two on the drop? Weird. Especially with wet ropes. Jesus. 

Bill Lawry · · Albuquerque, NM · Joined Apr 2006 · Points: 1,696

I used an auto block for a year before giving it up. Still, that video depicts an auto block setup that is about as poorly done as could be.

More generally, the number of variables is indeed large including the diameter of the rope(s) and the diameter of the autoblock (or how stiff / supple it is).

Getting the Goldilocks rig without much testing is non-trivial ... that being a rig that can be slid down with relative ease while still having the potential to make that surprise grab (unattended).   

And the testing should be without manual pre-tensioning of the hitch unless you are ok with relying on the need for it.  Edit: Once figured out, don't automatically assume that config will perform well on a different diameter of rope(s).

DrRockso · · Red River Gorge, KY · Joined Sep 2013 · Points: 367
Nick Goldsmith wrote: DR Rockso. your 80ft deck happened because they auto block was not set up properly.   if they had enough wraps around the rope for it to actually grab effectively grabbing the auto block itself will actually make it work better not worse. if it's wrapped so loose that it releases when you grab it its loose enough that it won't grab effectively anyways.
Nick, I was a rescuer not the victim, but I'm sure having not been been there you know more about the accident than I do, the autoblock was set up correctly and double checked by a rope rescue tech instructor and former climbing guide. The problem was the rappeler kept his hands tending the autoblock so it did not engage. 
rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526

I think a lot of people count on autoblocks for things friction knots can't do.  You have to release the autoblock in order for it to grab.  In a situation in which control is lost, it is highly unlikely that someone struggling to hang on to the brake strand will just up and let it go (there have been tests confirming this), and beyond that, once the rope is moving, the ability of the autoblock to catch and hold may be diminished.  The net result is that an autoblock can be truly counted on only if (1) it is properly installed and (2) the rappeller is rendered unconscious or experiences something that causes them to completely let go.  I think this means that an autoblock as a backup for loss of control in a rappel because of inadequate device friction is a very dicey bet.  Just my opinion.

L Kap · · Boulder, CO · Joined Apr 2014 · Points: 95
patto wrote: The discussion is linked in the video.   You can read it here:

http://www.bogley.com/forum/showthread.php?62220-Rap-accident-in-Rubio-Canyon-60-fall

I didn't read all 5 pages of comments. Most of them were not relevant to the question of extending a rappel. It was a fascinating peek into the minds of canyoneers and how they think about things differently than rock climbers. Like seriously, one of their big take-aways was "don't use an autoblock or you'll get reliant on it - just train yourself to never let go of the rope". Yeah no. We're not going to agree on that one.

My big take-away was that this was an inexperienced rappeller (on the thread linked to the video they said he had less than 25 raps) who made many mistakes and was damn lucky he was wearing a helmet to protect his head from that big thwack and gloves to grab onto the rope and slow his fall without getting his hands skinned. He clearly didn't know how to set up an autoblock correctly and should not have been left to his own devices to set up a rap through a waterfall with slippery feet. And his partner could have increased safety by giving him a fireman's belay rather than taking video.

Extending his rappel would not have prevented this accident (and odds are not good that he could have set it up correctly). He was not using enough friction, didn't wrap the autoblock correctly, and he completely let go of his brake. Usually when people talk about reasons to extend the rappel, it's so that the autoblock can't get sucked into the ATC and prevent it from catching. I didn't see anyone suggest that's what happened here.

Although it would have been a great idea for this guy's partner to pre-rig him so that he couldn't mess it up, and that is generally done with an extended rappel. 

Crag Hag · · Unknown Hometown · Joined Oct 2017 · Points: 17
DrRockso wrote: At least three things went wrong here, that are necessities to safe simul-rappelling, in my personal opinion these are mandatory for 99% of situations, when simul rapping.

1. Failure to close the system (No knots)
2. Failure to use an assisted braking device or hand free backup.
3. Failure to stay within a close distance to one another, for communication and as a reminder to keep the rope weighted at all times, even on a ledge or when reaching the ground.

Statistically very few rappelling accidents happen when the first two are adhered to. We see a few happen in setup, like putting only one of the strands through the ATC. Statistically in EPC, There have been few Simul-rapping accidents because those who are simuling generally are more aware of the dangers and take the extra safety precautions. Where as it is more common for those using traditional techniques to not tie knots or use a backup.

+1 for this comment.

#3 in particular... I find that keeping the rope weighted at all times and working simultaneously is so, so important.

All in all simul rapping should be a selectively used technique and should only be used when 100% necessary. The severe consequences/margin for errors aren't worth the time saved, IMO.

Nick Goldsmith · · Pomfret VT · Joined Aug 2009 · Points: 440

DR Rockso. I don't care how experienced the guy was supposed to be the friction knott was not tight enough if it didn't grab with the rappelers hand on it.  You can set them up like that and they work fine at the beginning of the rappel but won't work at all at the end of the rappel when there is less weight of the rope pulling down. the only way to set it up so that it works both at the top and the bottom of the rappel is to make it tight enough that its a PINTA to slide while starting your rappel. by the time you finish the rappel it is almost slides easy but it will still grab regardless of if you grab the knott.   set it up so it  slides easy at the top and it will not grab at the bottom of the rappel and it will also not work if the rappeler grabs it. 

DrRockso · · Red River Gorge, KY · Joined Sep 2013 · Points: 367
Nick Goldsmith wrote: DR Rockso. I don't care how experienced the guy was supposed to be the friction knott was not tight enough if it didn't grab with the rappelers hand on it.  You can set them up like that and they work fine at the beginning of the rappel but won't work at all at the end of the rappel when there is less weight of the rope pulling down. the only way to set it up so that it works both at the top and the bottom of the rappel is to make it tight enough that its a PINTA to slide while starting your rappel. by the time you finish the rappel it is almost slides easy but it will still grab regardless of if you grab the knott.   set it up so it  slides easy at the top and it will not grab at the bottom of the rappel and it will also not work if the rappeler grabs it. 

At the risk of some beginner taking anything you have to say seriously, you have no idea what you're talking about. A tended autoblock will not catch you if it continues to be tended and if you are setting it up so tight at first that it's a pain in the ass to go down then you're doing it wrong. Either choose a different material, or modify your technique. The Sterling Hollowblok works quite nicely for many rope many rope diameters. 

Nick Goldsmith · · Pomfret VT · Joined Aug 2009 · Points: 440

that's funny I only have a couple thousand hrs using the things.. Everyone always sets em up and tests them at the top of the rappel. next time you set it up with your nice loose wrap that will hold just fine with 60m of rope hanging under it and yes it will slip if you grab it.  Rap down 40m and let go. It will not hold. Add one more wrap. now its much slower, you have to work a bit to get it through at the top of your  rappel but if something happens on the lower 3rd of your rappel it will actually grab and if you grab it accidently it will still work..  but what the hell do I know...

DrRockso · · Red River Gorge, KY · Joined Sep 2013 · Points: 367

If in 1000's of hours of practice you haven't figured out how to set up an autoblock that catches correctly without it being a pain in the ass then I am even more concerned than I would have been if you started climbing last week. 

revans90 · · Unknown Hometown · Joined Oct 2013 · Points: 50

Your all quibbling over the auto block when the doofus let go of the brake hand..........
The other ropes a pull chord, hopefully they werent fiddle stickin’....
I’m curious to how simul rappeling is considered more dangerous then normal? Is it the fact that when there is a fuck up that two people rappelling resulting in x2’s the possibility of injury? What’s the difference if you fuck up on a normal rappel  vs simul?

Glowering · · Unknown Hometown · Joined Oct 2011 · Points: 5
revans90 wrote:I’m curious to how simul rappeling is considered more dangerous then normal? Is it the fact that when there is a fuck up that two people rappelling resulting in x2’s the possibility of injury? What’s the difference if you fuck up on a normal rappel  vs simul?

It’s covered in the thread above. 


I use an autoblock on the leg loop all the time. 3 wraps of 6mm supple cord on two ropes, it’s a tad bit tight at the top, only a minor issue if it’s not a vertical and my whole weight is not on the rope. And it locks up fine at the bottom.
DrRockso · · Red River Gorge, KY · Joined Sep 2013 · Points: 367

Actually the case I mentioned the party never let go of the brake strand. Simul-Rappelling is inherently more dangerous because a mistake by either partner likely results in both parties falling. It assumes reliance on a counterbalance and there are additional failure modes not present in traditional rappelling, such as one partner unweighting the rope or taking off their device, as well as concerns with differently weighted partners. Some of these concerns can be addressed in different ways.

Many rappelling techniques are completely safe when done perfectly, so what is being discussed here is which techniques are more fool proof, less prone to error, and have the least consequences if an error is made. Of course the answer of which system to use all the time isn't easy or feasible because different situations have a different ideal technique, and that is where judgment and experience combine with your tool box to make good decisions. 

JaredG · · Tucson, AZ · Joined Aug 2011 · Points: 0
L Kap wrote:

Like seriously, one of their big take-aways was "don't use an autoblock or you'll get reliant on it - just train yourself to never let go of the rope". Yeah no. We're not going to agree on that one.

Ha, that is pretty much my perspective.  I think autoblock knots ingrain bad habits that, combined with the added procedural complexity at each rap station, make them frequently more dangerous than avoiding the "backup" altogether.

Regarding the OP, simul-rapping seems only peripheral to the Gobright accident.  He didn't let down enough rope, then rapped off the ends.  The same thing could have happened with a single-person rap.

Simul-rapping is riskier mostly because one mistake tends to have about twice the consequences (2 climber injuries instead of 1).  In this case, the other guy was basically fine.
Glowering · · Unknown Hometown · Joined Oct 2011 · Points: 5
JaredG wrote: 

Ha, that is pretty much my perspective.  I think autoblock knots ingrain bad habits that, combined with the added procedural complexity at each rap station, make them frequently more dangerous than avoiding the "backup" altogether.

Disagree. What bad habits? Whenever I rap without an autoblock I think about how all it would take is losing control of that hand (lose footing and fall on that hand, hit by rockfall, etc. unlikely but possible) and you fall.

Simul-rapping is riskier mostly because one mistake tends to have about twice the consequences (2 climber injuries instead of 1).  In this case, the other guy was basically fine.

I’d say it’s riskier because human error is the main cause of rappel accidents and you are approximately doubling the chance that would happen since two people have to not make errors. 


Guideline #1: Don't be a jerk.

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