Post by Chad Dubuisson on Mar 25, 2008 22:08:59 GMT -5
Good grief, I should have weighed in sooner!
As the guy who actually tied the knot & caused this accident, I suppose after reading this thread & the British threads of how the Brits consider us total fools, an explanation is in good order. Get it from the horse's mouth, as they say! Rick was leaning on me to show him how this worked, so he is not to blame in any way other then for getting on rope at all.
Ok, specifically, just to clear the air, I learned this technique years ago, perhaps 16 years ago, watching a group of guys from, yes, I believe they claimed they were from Canada, but I'm not totally sure. I was still a fairly new caver & had only learned vertical techniques within that year. Who I learned that stupid technique from isn't important, as I can't remember names from that long ago and the fault lies with me for not learning better. What is important is that it was wrong, flawed & I should have learned a better way by now.
A very similar technique is described in the book, On Rope, in the chapter on rigging. I know because I own the book & worked for one of the authors who wrote it. The difference between what I did & what is suggested in the book is the absence of a large metal washer to effectively jam the knot against the pull-down ring. Had I learned to use a washer, had those who showed me how to do this used a washer, I can safely say I doubt there would have ever been an accident.
I recently had re bolted the cave with chain pull-down stations, complete with SMC descending rings at each pitch head. The internal diameter of these rings is about 1.5 inches.
???Just for the record, I nor Rick run any sort of "adventure company". I don't know where that came from, but I did work for On Rope 1 at the time, which sells caving gear and that is where Karen interviewed me at. You can't read too much from that video she shot of my interview, as usual, the news media never tells the whole story, nor did she use the footage of the actual knot I ended up using, she only showed it as I was tying it, partially complete, saying "hey, let me get a shot of you tying that". I came to realize after her report that the news media will always twist things to make their story sound better.
I have about 17 years of hard, vertical caving experience & Rick has close to 30, so we weren't a couple of newbies. We're both on the local cave rescue team & consider ourselves extremely knowledgeable in vertical techniques. Rick, despite his experience, had yet to do a pull-down trip. This was to be his first time & I was to be his guide, not only through this cave, but in the pull-down technique. He completely trusted me to show him how this is done. I have completed perhaps 30 or so pull-down trips in my career, all without incident until and since this accident. I had taken perhaps 6-8 trips through this specific cave before this accident, including taking members of the rescue squad through earlier that year.
I fully admit that my technique could have been safer. Period. This was a case where I learned a faulty technique many years ago & carried that faulty knowledge until this accident, never finding a need to improve my knowledge base because what I always did always worked, understand? :-[I'm ashamed that it took this accident to show me the error in using that technique. I'm still haunted by the nightmarish visions of the knot pulling through, watching the chains recoil into the air about a foot, watching that pull cord go zipping through the ring & following him down the pitch. I instinctively lunged for that cord as it zipped through the ring, almost falling myself down the pitch after him, as I was back from the lip & not clipped in with my tails at that moment.
Several times, I've doubled the rope & used either both sides or isolated one side with a figure 8 and clipped it to the other side with a krab. The techniques of the French, the British & American cavers where not lost on me. I'm aware of them all and consider myself one of the few american cavers who are well versed in european rigging styles.
Brad is right though, had we been using a larger diameter rope, this likely wouldn't have happened. The actual knot I tied was a triple overhand knot, with a single figure 8 knot tied on top of and backed up onto the triple overhand, or barrel knot. This, even in 10mm rope, is a large knot. Tie it sometime for yourself. Tie a single barrel knot, then tie a figure 8 and tighten it down over onto the barrel knot. Brad's also right that the knot didn't fail at all, the technique did. Rick rappelled about 15' and did a hard stop, which initiated a compressive deformation of the knot, somehow allowing it to tighten up so small that, coupled with the torque of his quick stop, it made the knot small enough to pass through the descending ring.
Sadly, this was a preventable accident & I hope I'm not the only one who's learned anything from it.
I have had heavier, bigger guys use the same rope on the same pitch with the same knot & had zero issues. Rick is not a big guy.
The 4mm pull cord was also tied through the triple overhand, sort of a mis-matched barrel knot. To be frankly honest, I had used this technique several times with several other cavers in this very cave without incident, though in hindsight, it was perhaps only a matter of time. I make NO misrepresentations about it, there are much better techniques out there to do this & I have since become a master at them.
This is the current technique I use.
www.canyoneering.net/forums/showthread.php?t=58
I tie a clove hitch on a half round maillon & once closed, I tie an additional figure 8 on a bight a few inches down from the clove hitch & clip a locking krab into that as well at the end of the rope. Into this krab, I clip the pull cord.
Using this technique perhaps 4-5 times since Rick's fall on pull downs, I feel it is the best technique to use IF you are using a minimalist approach, as in a rope as long as the longest pitch plus a pull cord as long as that.
Why weren't we just using a doubled up twin line approach? Good question. I've done that many times & was into doing light, fast trips with 2 cavers. This technique allows for the minimum amount of rope needed to complete the cave & is very fast to pack up at the base of each pitch. It was simply a matter of choice & convenience. Nothing more or less. I had even bought a specific rope for doing just this cave, as I did Pryor Springs about once a month on average at that time, I just love that cave and showing it to other cavers. Now, since this accident, the upper entrance has been closed. I am attempting to contact & work with the landowner so that, perhaps, one day, cavers will be allowed to tour this incredible system again.
The bottom line is this, had I clipped a krab or maillon through the knot, there likely wouldn't have been any accident, nor any of the important discussion which has since come of it.
Perhaps, the discussion of this accident has saved someone's life, perhaps mine. I have since re-evaluated all of my knowledge in relation to rope work to make sure I'm using the safest, most up to date methods in every situation, especially when I get on rope.
Rick & I are still great friends and I see him often. He's walking around pretty well these days. In fact, this past weekend, we hiked around on his property, as I'm thinking of buying a piece of his land one day. He's very interesting in getting back underground & is ready to hang in a harness again. His recovery has been nothing short of amazing.
Chad
As the guy who actually tied the knot & caused this accident, I suppose after reading this thread & the British threads of how the Brits consider us total fools, an explanation is in good order. Get it from the horse's mouth, as they say! Rick was leaning on me to show him how this worked, so he is not to blame in any way other then for getting on rope at all.
Ok, specifically, just to clear the air, I learned this technique years ago, perhaps 16 years ago, watching a group of guys from, yes, I believe they claimed they were from Canada, but I'm not totally sure. I was still a fairly new caver & had only learned vertical techniques within that year. Who I learned that stupid technique from isn't important, as I can't remember names from that long ago and the fault lies with me for not learning better. What is important is that it was wrong, flawed & I should have learned a better way by now.
A very similar technique is described in the book, On Rope, in the chapter on rigging. I know because I own the book & worked for one of the authors who wrote it. The difference between what I did & what is suggested in the book is the absence of a large metal washer to effectively jam the knot against the pull-down ring. Had I learned to use a washer, had those who showed me how to do this used a washer, I can safely say I doubt there would have ever been an accident.
I recently had re bolted the cave with chain pull-down stations, complete with SMC descending rings at each pitch head. The internal diameter of these rings is about 1.5 inches.
???Just for the record, I nor Rick run any sort of "adventure company". I don't know where that came from, but I did work for On Rope 1 at the time, which sells caving gear and that is where Karen interviewed me at. You can't read too much from that video she shot of my interview, as usual, the news media never tells the whole story, nor did she use the footage of the actual knot I ended up using, she only showed it as I was tying it, partially complete, saying "hey, let me get a shot of you tying that". I came to realize after her report that the news media will always twist things to make their story sound better.
I have about 17 years of hard, vertical caving experience & Rick has close to 30, so we weren't a couple of newbies. We're both on the local cave rescue team & consider ourselves extremely knowledgeable in vertical techniques. Rick, despite his experience, had yet to do a pull-down trip. This was to be his first time & I was to be his guide, not only through this cave, but in the pull-down technique. He completely trusted me to show him how this is done. I have completed perhaps 30 or so pull-down trips in my career, all without incident until and since this accident. I had taken perhaps 6-8 trips through this specific cave before this accident, including taking members of the rescue squad through earlier that year.
I fully admit that my technique could have been safer. Period. This was a case where I learned a faulty technique many years ago & carried that faulty knowledge until this accident, never finding a need to improve my knowledge base because what I always did always worked, understand? :-[I'm ashamed that it took this accident to show me the error in using that technique. I'm still haunted by the nightmarish visions of the knot pulling through, watching the chains recoil into the air about a foot, watching that pull cord go zipping through the ring & following him down the pitch. I instinctively lunged for that cord as it zipped through the ring, almost falling myself down the pitch after him, as I was back from the lip & not clipped in with my tails at that moment.
Several times, I've doubled the rope & used either both sides or isolated one side with a figure 8 and clipped it to the other side with a krab. The techniques of the French, the British & American cavers where not lost on me. I'm aware of them all and consider myself one of the few american cavers who are well versed in european rigging styles.
Brad is right though, had we been using a larger diameter rope, this likely wouldn't have happened. The actual knot I tied was a triple overhand knot, with a single figure 8 knot tied on top of and backed up onto the triple overhand, or barrel knot. This, even in 10mm rope, is a large knot. Tie it sometime for yourself. Tie a single barrel knot, then tie a figure 8 and tighten it down over onto the barrel knot. Brad's also right that the knot didn't fail at all, the technique did. Rick rappelled about 15' and did a hard stop, which initiated a compressive deformation of the knot, somehow allowing it to tighten up so small that, coupled with the torque of his quick stop, it made the knot small enough to pass through the descending ring.
Sadly, this was a preventable accident & I hope I'm not the only one who's learned anything from it.
I have had heavier, bigger guys use the same rope on the same pitch with the same knot & had zero issues. Rick is not a big guy.
The 4mm pull cord was also tied through the triple overhand, sort of a mis-matched barrel knot. To be frankly honest, I had used this technique several times with several other cavers in this very cave without incident, though in hindsight, it was perhaps only a matter of time. I make NO misrepresentations about it, there are much better techniques out there to do this & I have since become a master at them.
This is the current technique I use.
www.canyoneering.net/forums/showthread.php?t=58
I tie a clove hitch on a half round maillon & once closed, I tie an additional figure 8 on a bight a few inches down from the clove hitch & clip a locking krab into that as well at the end of the rope. Into this krab, I clip the pull cord.
Using this technique perhaps 4-5 times since Rick's fall on pull downs, I feel it is the best technique to use IF you are using a minimalist approach, as in a rope as long as the longest pitch plus a pull cord as long as that.
Why weren't we just using a doubled up twin line approach? Good question. I've done that many times & was into doing light, fast trips with 2 cavers. This technique allows for the minimum amount of rope needed to complete the cave & is very fast to pack up at the base of each pitch. It was simply a matter of choice & convenience. Nothing more or less. I had even bought a specific rope for doing just this cave, as I did Pryor Springs about once a month on average at that time, I just love that cave and showing it to other cavers. Now, since this accident, the upper entrance has been closed. I am attempting to contact & work with the landowner so that, perhaps, one day, cavers will be allowed to tour this incredible system again.
The bottom line is this, had I clipped a krab or maillon through the knot, there likely wouldn't have been any accident, nor any of the important discussion which has since come of it.
Perhaps, the discussion of this accident has saved someone's life, perhaps mine. I have since re-evaluated all of my knowledge in relation to rope work to make sure I'm using the safest, most up to date methods in every situation, especially when I get on rope.
Rick & I are still great friends and I see him often. He's walking around pretty well these days. In fact, this past weekend, we hiked around on his property, as I'm thinking of buying a piece of his land one day. He's very interesting in getting back underground & is ready to hang in a harness again. His recovery has been nothing short of amazing.
Chad