Rappelling- Be Vigilant!

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Mighty Hiker

climber
Vancouver, B.C.
Nov 23, 2011 - 04:13pm PT
http://www.supertopo.com/climbing/thread.php?topic_id=1662153&msg=1663082#msg1663082

An elsewhere in the thread, IIRC. Speaking of which, should the heavier climber(s), including gear etc, be the ones to go first? Does 10 or even 20 kg really make a difference, in context of the forces involved?
choo.choo

Trad climber
New York
Nov 23, 2011 - 04:14pm PT
Here's my near-death f-up with rapping about 20 yrs ago. My partner, Wes & I had just topped off the Nose at the end of a 3 day adventure at the end of May. That day we had to follow, then struggle through a single party of seven climbers (who were on day 6), so we were frustrated by that experience, tired from a full day's climbing and also out of food and water.

We wanted to be down on the valley floor before sun set in about two hours -- especially since Wes' girlfriend had a gourmet picnic waiting for us down by the Merced river. So I got the haul bag and Wes got the rack & rope and we packed it down to the standard rap off point.

I went down the rope first with the haul bag on my back. Well I had never rapped with just a heavy weight on my back (and with my center of gravity much higher and behind me). It probably weighed 50 lbs to my 130 lbs. The rope went through my Figure 8 REALLY fast.

At one point I had to go over a bulge and got flipped nearly upside down. I grabbed the brake hand end of the rope with both hands and held on for dear life.

I managed to right myself and then inch down the rest of the rap.

Lessons learned: I should have added more friction to my rappel device to account for the extra weight of the haul bag. A backup like a prussik or an autoblock would have been good too! Having Wes lower the pig to me after I rapped would have been another decent option. I don't think we tied knots in the end of the rope or tied the ends together -- even then I think a knot could have slipped through my Figure 8 if I had lost control of the rappel.

p.s. we did make it back to the base just after sunset and had a glorious dinner!
Toker Villain

Big Wall climber
Toquerville, Utah
Nov 23, 2011 - 04:21pm PT
Pardon me, but where is the "Repelling- Be A Vigilante" thread?
A5scott

Trad climber
Chicago
Nov 23, 2011 - 04:32pm PT
Very good, useful post. it's easy to get complacent on the trade route rap stations, but my partner and I always check out the rap station, sometimes add new cord, and cut out a ratty sling.

it's morbid, but i have a bunch of the "Accidents in north american mountaineering" books, and they describe all the recorded accidents. lots of injuries/deaths on repel/descent that could have been totally avoided

scott
HighTraverse

Trad climber
Bay Area
Nov 23, 2011 - 06:10pm PT
I went down the rope first with the haul bag on my back. Well I had never rapped with just a heavy weight on my back (and with my center of gravity much higher and behind me). It probably weighed 50 lbs to my 130 lbs.
Easy enough to rig a quick and dirty chest harness with a double length sling (think figure 8 sling around your shoulders with the end loops coming together at your chest). Clip it to the rope with a 'biner to take some of the weight. Keeps you from flipping over backwards.
I've used this with no troubles.
Any other thoughts?
md307

climber
jackson, wy
Nov 23, 2011 - 06:19pm PT
The weakest commercial ones were the old skinny SMCs. They rated @ 3000 lbs new, but they were hollow and with wear, 300 may be a fact for an old one.LOL The new SMC's are much fatter and rate @7000 lbs. Fixe stainless rap rings are crazy strong, will minimally wear and rate at 12,500lbs when new.
true, sorry about the fast post. I deleated that part.
A5scott

Trad climber
Chicago
Nov 23, 2011 - 11:17pm PT
haha, I'm still here... but my partner had me rap first with this anchor backed up with cams... my weight to test the anchor. I think it was actually better than this looks though. it was a few years ago. notice the thin hollow rap rings.

scott


donini

Trad climber
Ouray, Colorado
Topic Author's Reply - Nov 24, 2011 - 02:29am PT
Looks bomber to me, two natural anchors.
Ed Hartouni

Trad climber
Livermore, CA
Nov 24, 2011 - 02:51am PT
when using the vegetation it helps to know what the species characteristics are...
my wife is always aghast when she sees pictures like that, knowing what the typical root structures are and such, she doesn't climb so it doesn't help me at all, except to be wary.

the block looks bomber though... but maybe not if the tree is holding it in place
TWP

Trad climber
Mancos, CO
Nov 27, 2011 - 10:29am PT
In-days-gone-by when reading the numerous "He rapped off the end of the rope and died" stories, I complacently wondered, "How could he have been so stupid?"

I found the answer one fine day.

As I too complacently rapped to near the end of the rope (no knot backup either, rapping into a hanging stance none the less) I learned the amount of friction through the rap device DRAMATICALLY and RAPIDLY goes from "good" to "nothing" as you near the end of the rope.

If you are sliding blissfully down the rope, you can pass the point of no return before you know it.

ERGO

SLOW WAY DOWN went approaching rope's end (last ten plus feet) so this loose of friction does not take you by surprise.

Of course, the self-righteous might say, "but I'D NEVER forget to knot the end of the rope." But that, as with all bromides, will be ignored one fine day, and the above-advice comes back into play.
apogee

climber
Nov 27, 2011 - 12:15pm PT
A little on the tri-axial side, though.
rgold

Trad climber
Poughkeepsie, NY
Nov 27, 2011 - 02:59pm PT
To the extent that one can tell things from a photo, I'd concur with those who think there is nothing sketchy-looking about that tree-and-thread rap anchor. Of course, on a 200-foot cliff with a carriage road underneath, there is no time penalty for being extra prudent, so backing the rig up for the first person down is certainly a reasonable option.

For stations whose anchor points are clearly substantial, as appears to be the case here, the biggest concern is the webbing, and the biggest concern about the webbing is the parts you can't see.

Sometimes the invisible parts are just behind a tree that grows at an acute angle to the cliff face and perhaps has lots of branches that interfere with getting a good look behind the tree. It is critical to do this anyway. I have found slings that looked fine in front that were so abraded in back by their contact with the bark that they could be (and were) snapped by a vigorous jerk.

Threaded slings can be more of a problem. If the slings are loose enough to rotate so that the portion behind/inside the thread can be brought out into the light of day and inspected, then all is well. If the slings won't budge and you can't peer into the thread region to inspect what is there, then I think extreme caution is called for, no matter how good everything looks on the surface.

There could be sharp edges inside, animals might have gnawed on the hidden parts, and channeled water might have contributed to far more deterioration inside than there is outside. I think such anchors need to be backed up and then gently bounce tested. (Gently because you don't want the test to further cut the sling on a hidden sharp edge.) If it is possible to cut away and remove the resident slings and install your own, that is certainly the way to go, but sometimes things are too wedged to manage this.
HighTraverse

Trad climber
Bay Area
Nov 27, 2011 - 04:53pm PT
The Gunks anchor has been bugging me for a couple of days.
On the face of it, that anchor looks safe.
I'd want to be sure the threaded slings are OK.
The base of that tree is not so OK.
1: Looks as if the green webbing has cut through the bark and is being grown over by the trunk. That makes the sling questionable. It may be detiorated where it's grown over and you've no way of knowing. Also, if it's grown over, that green sling is much older than it looks.
2: I'm never sanguine about a tree whose trunk is less than the diameter of my forearm. So that tree is marginal anyway.
The way it's sharing the load with the threaded sling is good.
If that's a popular route, bolts might be in order to increase safety and reduce environmental impact.
Toker Villain

Big Wall climber
Toquerville, Utah
Nov 27, 2011 - 06:17pm PT
High Traverse your chest sling advice is poor.

The thing to do with a heavy load is to clip it to the bottom of the harness biner with the descender and jug so the weight goes right on the rope.
With a little practice one can stop and still unweight the jug and continue.






EDIT for next post;
rgold,
ARGH!!!!
Climbers have routes.
Trees have roots.
rgold

Trad climber
Poughkeepsie, NY
Nov 27, 2011 - 08:33pm PT
In the Gunks, a tree like that, with a root system heading straight into the cliff in a horizontal crack, is usually pretty good. Of course, one would test the thing by yarding on the either the slings or the tree base (suitably protected in case of failure, of course.) This one looks like it belongs to the genre that doesn't budge at all under such tests. Still and all, I don't think I'd use it as the only anchor, not when you're on a 200 foot cliff and are only rappelling for convenience anyway.

A scarier situation occurs when the roots are in soil that is thin and poorly attached, as in the picture below.


In spite of the new slings on the tree itself, the entire tree and the soil it is rooted in are ready to pitch over the edge, and did so of their own accord within a few weeks of this shot.

(Naturally, we removed the slings from the tree after taking this picture. The nature of the route has the party established underneath the tree, in a position in which the soil pulling away from the rock is not visible.)

Edit: After appropriate scolding from Piton Ron above, I changed the tree's "route system" to its "root system." My typing abounds in heterographic substitutions...
HighTraverse

Trad climber
Bay Area
Nov 28, 2011 - 06:41pm PT
Piton Ron
I agree that the chest sling support if you're rapping with a load won't work for a heavy load. The OP mentioned 50lbs for which I think it's OK. Certainly not for a pig-sized load. Although I'm certainly open to correction on even my limited claim.

The thing to do with a heavy load is to clip it to the bottom of the harness biner with the descender and jug so the weight goes right on the rope.
With a little practice one can stop and still unweight the jug and continue.
I've read this about 10 times and still don't understand your point. We're talking about rappelling, not jugging.
Even for jugging, it's not clear to me what you mean.
cheers.
choo.choo

Trad climber
New York
Nov 28, 2011 - 10:36pm PT
since my post a few days back I ran into this post about "Riding the Pig". Seems like a great way to rap with a pig (instead of having it on your back!).

http://www.terragalleria.com/mountain/info/yosemite/pig-east-ledges.html
Rattlesnake Arch

Social climber
Home is where we park it
Nov 29, 2011 - 07:04am PT
Of course, on a 200-foot cliff with a carriage road underneath, there is no time penalty for being extra prudent

Saving time is the only reason to rap at the Gunks, otherwise there are pleasant walk-offs.



I'm being a bit facetious here. It takes little time to back up an anchor, I know.

But I've noticed parties waiting in line to rap, near the Uberfall, when they could have walked off. And sketchy slings have sprouted only 20 ft from other perfectly good rap anchors that didn't need a back-up.

Back in the early 70's when I learned to climb there, we seldom used to rap. I'm not sure why, or if I even thought about it, it just wasn't done as often..
donini

Trad climber
Ouray, Colorado
Topic Author's Reply - Nov 29, 2011 - 10:10am PT
I've survived many epic descents in the mountains with difficult rappelling, but, one thing for sure, I NEVER rap when there is an easy walk off. Rapping the Uberfall makes no sense.
HighTraverse

Trad climber
Bay Area
Nov 30, 2011 - 01:29pm PT
There's a failure analysis concept that it usually takes more than one mistake for a system failure.

A tragic accident which illustrates the concept:
From a link posted by Clint on a Pinnacles thread.
http://www.stanford.edu/~clint/pin/acc/765tomb.htm
The salient bits extracted:
Several factors contributed to this tragedy:
(1) The use of only a waist loop to support the body weight during the rappel.
(2) The use of a Prusik Knot back-up to safeguard the rappel.
(3) The novice climber's inability to relieve the strain on his waist and chest.
(4) The lack of sufficient equipment by the second climber to effect a quick rescue.

So let's ignore items 3 and 4 and go to the original setup which led to the rappel failure, items 1 and 2
The use of a carabiner friction brake for descending a rappel line is an accepted and proven technique. Keep in mind that this was 1976. Attaching this brake system to a waist loop ONLY is not commonly practiced. This method apparently was preferred by ... and he taught it to his students. Its main advantage seems to be that of simplicity - the wrong 'advantage' when safety is key. Most climbers prefer a seat harness to ease the strain on the waist. One has only to hang free a few seconds from a waist loop to realize that the strain on the waist and thoracic region can be very painful and breathing made extremely difficult.

The simple expedient of tying a Prusik knot to the rope and clipping it to the waist loop protects against accidental detachment from the carabiner brake and losing control of the rappel. It also increases security at the end of an unknown rappel.
However, ITS USE IS A QUESTIONABLE PRACTICE. It inhibits freedom of motion. The knot can tighten up out of reach. There is also a real difficulty in negotiating overhangs and the knot is virtually impossible to loosen under tension. Also, it must grip instantly in the event of a free fall or the rope can suffer damage from the extreme friction and heat generated.
This is why I've gone to an Autoblock set below the belay device. Which has it's own caveats/; mainly keeping it short enough that it can't run up against the belay device and thereby be kept loose.

The accident report is by Jody Langford who really knew his stuff.
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