15. Snow Anchors – Using your Ice Axe
In this video we take a look at anchors using an ice axe. An ice axe can be used as an effective snow anchor, in a couple different ways.
Vertical Anchor – The first method involves pushing or driving the shaft down into the snow, to create a vertical anchor. The best orientation is to drive the shaft in at an angle 10 degrees back from the line perpendicular to the slope. Again, snow anchors should be angled back relative to the PERPENDICULAR line of the snow surface. 10 degrees back from vertical is wrong and dangerous. When you place a picket at too steep of an angle in the snow it will slice out.
This type of anchor only works in firm snow, where you need to stomp on the head of the axe with a boot, or drive it in with a second tool. If the shaft goes into the snow too easily, this is an indication that the snow is not strong enough to hold a vertical anchor.
Horizontal Anchor – If the snow is not bonded well enough to hold a vertical anchor, the ice axe can be buried as a horizontal anchor, or what is also called a “deadman,” or T trench anchor.
A trench will be dug that is longer than the axe length, and the pick of the axe should be pointed straight down when placed into the trench. A double length sling works well as an attachment point, that can be girth hitched onto the middle of the shaft.
Carve a small trench for the sling. This will look like a “T” which is why this is often called a “T” trench. Be careful not to make the trench for the sling too shallow or it will put an upward pull onto the Ice axe.
Once the axe is placed in the trench you can backfill it with snow to increase your confidence in the anchor, but it should not be necessary if you have adequately angled the trench back a few degrees and carved out a pocket in the bottom of the trench to ensure the axe seats securely in the trench.
We hope you found this video helpful. Feel free to comment below with questions or thoughts!
Please remember, climbing is inherently dangerous. Climb at your own risk.