Cowtail question

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Cowtail question

Postby frbarton » Jul 28, 2015 8:36 pm

Some friends and I have been discussing our systems for ascending and a number of discussion points came up which I would love opinions on. Primarily, we were discussing weather or not a webbing sling can replace a cow tail for attaching your ascenders to your harness. We are of the opinion that the fact that the sling is static as opposed to dynamic is really negated by the short length of the line. Additionally, unless you're backing up your ascender with a Prussix, a shock load is far more likely to cause a release of the ascender than for the sling to fail. What do you guys think? Any glaring reason to use a dynamic cowtail as opposed to slings? Do you back up your ascenders with prussix in case of failure?
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Re: Cowtail question

Postby GroundquestMSA » Jul 28, 2015 8:52 pm

There are several long discussions on this forum on the topic. I'll look some up for you in a bit. Dynamic cowstails are widely considered mandatory, and retain their utility as shock absorbers even in such short lengths. But as many have observed, cowstails should never be subjected to a shockload. Despite all the noise over this issue, I suspect that the chances of a problem with static cowstails are incredibly slim. However, webbing cowstails are a bad idea for other reasons, primarily the ease with which they can get sucked into your ascenders. This has happened to me and probably many others.

No one backs up ascenders with a prusik knot.
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Re: Cowtail question

Postby GroundquestMSA » Jul 28, 2015 9:10 pm

Have a wade through this

Or this

Maybe this

And this

Read this stuff with a clear head, and realize that a lot of the theoretical arguments have little or no practical application. I wouldn't want to make a choice for you, but I don't mind suggesting that, if you have properly learned SRT maneuvers, the dynamic/static decision is one of relatively low importance.
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Re: Cowtail question

Postby LukeM » Jul 29, 2015 7:42 am

Of course, ascending isn't the only time you'll be using your cowstails. The most risky situation for a non-dynamic cowstail would be when you're clipped into a hard anchor; maybe while rigging or negotiating a rebelay. If you happen to be not thinking clearly and raise your main attachment point above the anchor and then slip the idea is that you could easily injure yourself with a static cowstail. In practice I'm not really sure how likely injury is but for a few dollars worth of dynamic rope it seems worth it to mitigate the possibility.
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Re: Cowtail question

Postby CaverCarl » Jun 10, 2018 8:38 pm

Lot's of thoughts on this.
Why would you want to give you any dynamic on such a short section?
Yet if you opt for a dynamic cow's tail, and routinely climb on it does the "dynamic eventuly stretch out?
I did use a 11/16" wide webbing cows tail for a while. I also do remember an annoying instance when it was sucked into my croll.

1-What is the load you cows tail will be expected to hold.
2-What is your personal safety factor comfort load, 5:1, 10: 1, 15:1? (also what do you, in cave gear with pack weigh?)
3-What shock load (or fall protection) do you expect in the way you use your cows tail.

My answer's are 225 lbs.
10:1 (That means a minimum breaking strength of 2,250 lbs after deducting for knots, like a figure 8 it needs to be 3,800 lbs strong) 8mm nylon static is just a little short of that at 3,200 lbs.
Yes I expect to use it occasionally as fall protection as I clip into the back up anchor rig and chimney out to the main rig point and begin to rig.
I use 9mm dynamic.
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