The Two Stroke Cold Smoking Gun

AST2 Field Day: On the hunt for learning examples of the current persistent slab problem. We found it easily at 2040m in open N facing trees: the class dug a 3 meter long snow pit wall for demos, in the process of isolating a column we had a sudden collapse propagating across the entire 3 meter pit wall, still attached on two sides, down 35cm on surface hoar / facet combo (ECTPV). Difficult to describe in words but you could certainly also feel a crust down +/- 35cm while riding with a slab initiating behind our sled tracks but sluggish to get moving beyond that - curious if cutblock surface roughness / anchors were playing a role. Adjacent large open slope: natural sz 2 avalanche observed (48 -72 hours old), suspected PWL failure as it broke below ridgeline (cornice was still intact).