Friday, April 19, 2013

Extending Your Rappel

We have talked about extending a rappel in this blog before. However, to date we've been too lazy to make a video on the subject.  This is not the case with Climbing magazine's gear editor Julie Ellison. Julie made a very nice video on the subject of rappel extensions.

Following is the video:



There are a handful of additions that I'd like to make to Julie's notes.

Girth-Hitching the Sling

It is important that the sling is girth-hitched through the tie-in points on the harness. It should not be girth-hitched around the belay loop. This is because a girth-hitch crushes the loop and slowly wears it out.

Some choose to keep a PAS or a daisy chain attached to their belay-loop on a more or less permanent basis. This is very dangerous as it freezes the belay-loop in place, keeping it from rotating. The natural rotation of the gear-loop allows wear to disperse around the loop. When something is permanently girth-hitched to it, all the wear is focused into two places, wearing out the loop faster.  To avoid this, we recommend girth-hitching through the tie-in point.

Redundancy

Julie shows the clipping of the device inside the loop between the harness and the rope. To create additional redundancy in the system (at least while rappelling) it is possible to clip the device into both loops. That way, when you clip the end of the system back to yourself, you have a level of redundancy.

Type of Sling Used (Dynema)

In the video Julie is using a Dynema sling. These slings don't do well in a factor two fall.

A factor two fall could take place when you clip into your anchor above your anchor, and then slip. In tests completed by DMM, Dynema slings did much more poorly than nylon slings.  To see a video concerning this, click here.

Our recommendation is generally to use nylon slings in this application. But if you have to use Dynema, then you should be cognizant of this danger.

Third Hand - Autoblock

Julie shows clipping this into your belay loop, which is the correct place to clip the autoblock. However, many people clip it to their leg-loop when they extend the rappel. There is no reason to do this. If your belay loop is clear, why wouldn't you clip the autoblock to it? It's the strongest part of your harness.

Third Hand - Letting Go

Julie does make one off the cuff comment about how your autoblock will save you if you let go.  Indeed, that is the intent of the third hand. However, if the autoblock is loose or sloppy, it may not engage appropriately. As such, I generally still wrap the rope around my leg or tie a catastrophe knot below the autoblock in order to have some peace of mind when I have to go hands free.

Speed and Efficiency

One thing that was not mentioned in the video is that the use of extended rappels in a multi-pitch setting allows more than one person to clip in at the same time. This can significantly expedite a descent and also allows you to check one another to ensure that everything has been set-up right.

I personally tend to extend my rappels at every opportunity. There are some places where it's not terribly useful or realistic (like in a sport setting), but in trad and multi-pitch settings, it is definitely the way to go...down...

--Jason D. Martin

5 comments:

Gonzalo GarcĂ­a said...

A really good video... I share it in my fb... Thanks!! =)

www.climbforever.com

Newman said...

so... the girl in the video explains how to set it up, but never describes a situation in which this system would be useful.

other than simply being a safer method for rappelling, with a backup in case you lose control of the rope, or become knocked unconscious, is there a purpose for this system?

Jason Martin said...

Absolutely.

Please see my comments in the blog.

Here is the quick answer to your question:

1) Speed - more people can set-up at once.
2) Safety - you can check one another.
3) Control - It's easier to control your descent with an extension.
4) Tricks - There are more tricks that you can do (like rope climbing) if you're set up with an extension.

Jason

Tim Page said...

This system also reduces the likelihood that your hair or shirt will get stuck in your device, and keeps your autoblock away from your belay device.

Anonymous said...

The end of the sling can also be clipped into the rope you are going to pull at the bottom of the rappel. (As opposed to just clipping it into your harness) Once at the bottom you will know which rope to pull, the ropes will not be twisted and you will have more chances of a clean retrieval.