Technical information, news, research, and opinion on avalanches, snow safety, and winter backcountry travel.

Monday, November 21, 2016

Thursday, November 17, 2016

What Not To Do

I recently read an accident report about the death of a local skier. The accident report contained a photo showing skin tracks around Kendall Mountain. The skin track is a perfect example of how not to set a track. In fact, it's almost perfect in how it manages to expose the skier to the most hazard for the least gain. There are much safer routes available.

The first problem is that the skin track is unnecessarily exposed to avalanche starting zones. The track's location midway down the hill means that any avalanche that reaches the location of the skin track will have sufficient mass and velocity to knock a skier down and take them for a ride.

Where would this ride take an unfortunate skier?

The skin track is above trees, which are a well-known terrain trap, and the left-most section of the track traverses a small gully that is the perfect location for a deep burial.

I've drawn in an alternate skin track in blue that might work better and has the same number of kick turns. The alternate route through the trees on the right is also a perfect location for a meandering track uphill that wouldn't require any kick turns at all.

Is it laziness? Ignorance? Powder fever?

The skin track is especially interesting in light of the fact that all the downhill routes look pretty conservative!! Note that it doesn't look like anyone wanted to descend the slopes traversed by the track.

It doesn't really add up, does it? Choosing the most dangerous route up and the safest route down.


Seven years ago I wrote a blog post about how to analyze terrain for exposure.

http://avalanchesafety.blogspot.com/2009/12/terrain-observations-increasing.html

The model for terrain analysis I developed ( and still use and encourage others to use ) has the following parameters: Line-of-sight, open, confined, accumulators, obstacles, steep. Let's use the model parameters to analyze the terrain around the skin track:

Line-of-sight. Excellent line of sight. + 1
Open. Yes. -1
Confined. No. +1
Accumulators. Yes -1.
Obstacles. Yes -1.
Steep. Yes. -1.

The grand total?

-2

I never tell people "don't go" because I don't have that view of the world. Just be smart about it.