Indy pass slides 10/26/09
Witnessed a few slides today, both natural and skier triggered.
We noticed this natural release on the way up.
http://i195.photobucket.com/albums/z...g?t=1256600403
Before any internet second guessing takes place, I'll mention that the line that slide had significantly more snow than the lines that were skied, and the slide path was also below a significant cornice. I thought I got a better pic showing the starting zone, but I guess I didn't. It appeared to have started when wind loading that had stuck to the cornice broke, triggering the rest of it. Only the new snow from last night slid, about 1', which was heavily windloaded and thick. The bowl is a westerly aspect, with that particular chute facing a bit more northerly.
On my first run I kicked off this.
http://i195.photobucket.com/albums/z...g?t=1256600396
I cut the cornice with my ski pole getting small sections to break. When I'd cleared a five foot section, I dropped in with a tiny bit of speed, on the lower edge of my cleared section, angling towards the shallow shoulder. I expected the cornice to break, and planned on it breaking just above me, and pointing it with speed into the safe zone. I thought the chute might slide, but was still surprised when it did. Once I was in the safe zone I sat down and dug in pretty quickly just in case, and I managed to get a look over my shoulder, the chunk of the cornice that broke off was not very large, its hard to guess, but probably around 300 lbs. Not too much heavier than a person with gear really.
The (very) small slide to the right was triggered after mine simply by someone cutting the cornice with their pole.
Here's a closer look at the slide I triggered. You can't quite see, but the safe zone I went into had a pretty flat area, with a shallow enough snowpack I could have dug into the rocks if I'd needed to, and had no cornice above me.
http://i195.photobucket.com/albums/z...g?t=1256600399
This slide, along with a couple other natural point release's we saw from last night, were all the new snow sliding on top of all the old stuff. Most of these slides probably would not be fatal to be caught in, but the possibility for serious trauma from rocks still exists.
good technique for cutting cornice
I've came up with a good way of cutting cornice that I thought might help. When I am backcountry skiing I usually carry a whippit. This tool is really helpful in cutting cornice that is not scarry big. I hold onto the basket and extend the whippit out the the cornice edge and then pull the whippet back towards me. This will create a channel. I make two channels 6 feet apart and three to four feet deep and preferably choose an area that is overhanging. I will then attach my thin rope I carry, that has knots every 6-8 inches, to the end of my pole. This way I can fish it out over the edge without exposing myself too much. Then get the rope in the channel and start sawing away. Sometimes it helps to clove hitch a small rock in the center of the rope so that it hangs further beneath the cornice. This creates an awesome bomb of the backcountry! It does take a little time, however it is a good test. It's also easier to saw with two people, one on each end. In skethy severly overhanging cornice it might be a good idea to be anchored and on belay as well.
Just some thoughts... The snow coverage looks surprisingly good..
