Change-over from climb to rappel / Alpine Caving Techniques

[lostgravity]

I carry a third ascender (a Petzl Basic), and I use the following method:

(1) I put the Basic on my short cowstail if it is not already there and clip it onto the rope as high as it will go, moving the hand ascender (my upper ascender, a Petzl Ascension) up if necessary.

Out of curiosity, how much are the cams of your basic (on the short cowstail) and the ascension apart from each other when the respective lanyards are fully extended? Or: how much shorter is your short cowstail compared to the ascension's safety? :)

[NZcaver]

Just returning from the trees in the backyard, I have the following observations to make:

1. I wonder how you can have 10-20 cm between the ascenders and still have a long enough lanyard to load your descender and not the handheld ascender when taking off the croll. ;-)

2. Applying the ACT technique of taking the croll off and the short cowstail on top of the ascension instead doesn't even help me much. The length difference between my short cowstail and the ascension safety isn't that large that it would make this a safe bet in terms of avoiding to load the ascension instead of the rack when taking the short cowstail off again. I never had the impression that my short cowstail is too long, but maybe I need to revisit that in this context.

The length of your cowstails will provide the answer to your questions.

Assuming you use a double cowstail (with the long side normally connected to your upper ascender), here is one conventional method for determining "correct" length:

Standing up with your harness on and your cowstail clipped in, place your elbow tight against your harness maillon, forearm straight out from the body, palm facing up. The carabiner on the short cowstail should sit in the palm of your hand, with the knots tensioned tight and no slack in the rope. Now extend your arm out to full length in front of your body with your hand about level with your stomach. Again with the carabiner held in your hand, this should make a good length for the long cowstail used as a safety for your upper ascender.

For me, the short cowstail would end up being about 30cm (12in) long after being tied, and the long cowstail about 70cm (28in). This does not include the length of the carabiners. You could make the long cowstail a little longer, but be aware that when you tension your harness by sitting in it everything will ride up a little. This could put your upper ascender beyond the extent of your reach.