We traveled up across the meadow and up the difficult-to-navigate (log fall) lower East face of Elk after parking at Pocket Crk. Our goal was Elk bowl, then back down the face. We discussed considerable NWAC assessment. We felt the sun crust on more easterly/southeasterly aspects under the 8+ inches of new snow. We curved up and to the more protected NE slope where no sun layer was detectable (snow was now quite deep). We noticed small nonpropagating layers falling especially where the sun crust was palpable on the skin up. We discussed wind effects—there was noticeably less new snow (like 1-2 inches) on some small exposed ridges/spines right near our high point, where the avalanche was triggered. And we saw a cornice (small, maybe 10 feet long) on the leeward side of the small bowl above us. I struggled to skin across (while my partner stayed off the slope and watched me) and then I went back to the spine to boot pack up the last 20-40 ft to the upper ridge. My partner decided to keep traversing and continued my track, moving closer to the middle of this upper bowl.
I saw and heard him yell slide, struggle to dig in, and the larger ~50 ft wide bowl released above him (as I remember from just under the cornice and along most of the upper ridge line R3). I watched him get taken off his feet and rolled over a steeper section 20-30 ft.below him where he hit a dead tree stump with branches at low speed. He then (basically now buried he said) went through a large couple of willow bushes where the slope slightly moderated.
I was getting my splitskis on (which I had shouldered for short boot pack) and about to turn beacon to search mode and yelled for him. He responded after maybe 20 seconds. He wasn’t buried and dug himself out. He lost 2 skis and 1 pole. I traversed to the avy bed (which was largely moderately firm sun crust alternating w chalky snow) and skied down w skins on looking for his equipment. He sustained bruises to elbow and ribs. He walked out in my tracks.
Hopefully this is helpful for others. We stayed calm, backed each other up, and discussed avalanche terrain before the slide, but still made errors that could have been much more costly.