Alpine retreat anchors - Part 2
Premium Members can read the entire article here:
Note - This post discusses techniques and methods used in vertical rope work. If you do them wrong, you could die. Always practice vertical rope techniques under the supervision of a qualified instructor, and ideally in a progression: from flat ground, to staircase, to vertical close to the ground before you ever try them in a real climbing situation.
The techniques shown below are NOT standard anchor building practice. For normal anchors, clip a carabiner to your gear placements before you clip the sling/cord. These examples are retreat anchors for bodyweight rappelling only, when you want to conserve your gear.
Be it challenging weather, poor conditions, route finding errors, or general loss of mojo (a.k.a. “ambition exceeding ability”), there can be lots of valid reasons to turn around on an alpine route. It may not be something you actively planned for, but it needs to be handled with the same level of focus and detail as any other part of your climb.
When you retreat / bail (and yes, it’s “when, and not “if”), be it a one pitch sport climb or a major alpine adventure, the objectives should be similar:
Get to the ground in one piece
Have with each rappel anchor simple to build and easily strong enough to rappel on
Leave a minimum of gear behind
Let's be clear on one thing: this is no time to be a cheapskate. Yes, we hate to leave gear behind, but if you HAVE to leave your beloved #3 Camalot for a rappel anchor, then do it without hesitation. The simple question is, what's your life worth? At the same time, you don't want to over build your anchors, and leave behind gear that you might need lower down if multiple rappels are required.
What are the forces on the anchor when rappelling?
I recently came across a nice video from the meticulous gear testers at Edelrid. (Have a look at their “Edelrid Knowledge Base” on YouTube, they have lots of goodies there.)
Check out the screen grab below from one of their videos.
Short version:
If you bounce around on the rope like some special forces cowboy, you can generate between 2 and 3 kN as a temporary peak load.
When you rappel smoothly, the load to the anchor is pretty much your body weight.
Takeaway: rappel smoothly without bouncing to minimize force on the anchor.
Image: screen grab from https://www.youtube.com/watch?v=A7rKGDxrdTA
There are lots of ways you can rig a retreat anchor. Here's a good one.
Simple (easy to check)
Fast to rig
Plenty strong enough for rappelling
Requires minimal gear
Place two pieces of solid gear fairly close to each other (here a stopper and a piton). Starting with about 2-3 meters of cord (here, 6 mm), pass the cord through both anchor points as shown.
Tie a flat overhand bend to make a loop.
Tighten the knot, leaving tails of at least 3 inches / 8 cm.
Pull down the cord, making a “U” shape.
Girth hitch masterpoint on a taped gate carabiner. (Lots of other options here. If you have enough cord, you can tie an overhand knot. If you want to use a quicklink or rappel ring, that works. I'm showing my favorite method to keep things consistent.)
This approach is fast, requires minimal fiddling with knots, and uses a small amount of cord. Efficient use of materials is the main benefit to the girth hitch master point.
Potential downside, you need to leave behind some hardware to make the girth hitch. (If you had another foot or so of cord, you could tie an overhand on a bight and rappel from that rather than the girth hitch.)
If you're new to the girth hitch master point, yes, it's legit and yes, it’s redundant. Read a more on the girth hitch anchor here.
What if the anchors are farther apart?
What if you want to use a sling instead of cord?
Tying a cord directly to a stopper wire? How strong is that?!
