We were lucky to all come back today.
A member of my party of 3 triggered a wind slab at 7400 ft on a north aspect and was carried around 1500 ft where he came to rest on top of the debris uninjured.
This massive failure of decision making was preceded by several other mistakes that set us up for this failure. The first mistake we made was the assumption that, even with decent winds over the past several days, the slabs that had formed would be small and easy to avoid due to the lack of significant precip over the last week. Additionally, I assumed that past winds would not load our chosen aspect due to lack of snow available for transport on south aspects. The second mistake was to dismiss wind loading and reactive wind slabs we observed, because they were on a different aspect than our objective, that was actively loading, unlike ours. We failed at communicating alternate options for descent and following our gut feelings about the slope. These combined with several environmental factors, including a sketchy return climb and the wind howling in our face at ridgetop made a decision to ski cut the top of a chute all the more likely and unfortunate.
I watched in horror as my partner started his ski cut and had made it about 3/4 of the way across before the wind pillow fractured around him ( Location of 1st pic). In a last ditch effort to get off he turned and was taken out of my view in a white cloud and chunks about 12-16in tall. I watched as the debris fanned out below with a small black speck popping out at the last moment. Immediately, knowing the severity of the terrain below, the one remaining member of the party stayed on ridgetop with cell service to call 911 and I descended the bed surface noting the cliffs that the path traveled over and the lack of large crown. It appeared as if the entire slab slid away.
After traveling what felt like an eternity down the path, I found him sitting upright on the toe of the debris, uninjured. He noted, his skis popped off immediately and that he felt the snow slowing down when he was under and swam as hard as he could for the surface.
My decision calculus needs a new formula. I feel sad, angry, embarrassed and relieved that we all walked away from this.
We fell victim to a spring complacency that almost took my friends life.
FAC note: We're thankful the rider walked away and appreciate that the party reported the incident promptly, with images and takeaways. We'll incorporate this obs into an accident report in the next few days. From conversations with the victim, it appears he traveled about 2000 vertical feet, was under the snow most of the way, and suffered bruises and possible minor injuries to a hand and knee.
Forecast Hotline: 406.257.8402
Call or text an observation: 406.66AVYOB