This is the avalanche on Tincan Proper that happened on December 2, I was the first skier down the run, my partner triggered the avalanche following my tracks on top of the rib, in a section where the snowpack was shallow on top of the spine with protruding rocks hidden under a couple inches of fluff. Beneath the fluff in that area the snow seemed to be the bed surface of previous sloughs or avalanches that had removed the top of the snowpack, but without taking out the basal facets and a slab above them. The slab broke above my partner, he was able to hang onto the rocks, but just barely. The fracture propagated into deep snow on the loaded, west side of the rib with a crown face as much as 7 feet deep.