Amazing avalanche rescue video OCT 02 2009
A skier with a video camera on his helmet gets caught in an avalanche and then, four and a half minutes later, gets rescued. The good stuff starts around one minute in.
This was a decent sized avalanche. 1,500 feet the dude fell in a little over 20 seconds. The crown was about 1 - 1.5m. The chute that he got sucked through to the skier's right was flanked on either side by cliff bands that were about 30m tall. He luckily didn't break any bones and obviously didn't hit anything on the run out.
I had always assumed -- and this is likely based almost entirely on an episode of The Simpsons -- that you had options when buried by an avalanche...like digging yourself out or at least being able to move. Not so says the Utah Avalanche Center FAQ:
It doesn't matter which way is up. You can't dig yourself out of avalanche debris. It's like you are buried in concrete. Your friends must dig you out.
The FAQ contains a story by the director of the UAC about surviving an avalanche of his own; he confirms the concrete-like hardness of post-avalanche snow.
But after a long while, after I was about to pass out from lack of air, the avalanche began to slow down and the tumbling finally stopped. I was on the surface and I could breathe again. But as I bobbed along on the soft, moving blanket of snow, which had slowed from about 50 miles per hour to around 30, I discovered that my body was quite a bit denser than avalanche debris and it tended to sink if it wasn't swimming hard. [...] Eventually, the swimming worked, and when the avalanche finally came to a stop I found myself buried only to my waist, breathing hard, very wet and very cold.
I remembered from the avalanche books that debris instantly sets up like concrete as soon as it comes to a stop but its one of those facts that you don't entirely believe. But sure enough, everything below the snow surface was like a body cast. Barehanded, (the first thing an avalanche does is rip off your hat and mittens) I chipped away at the rock-hard snow with my shovel for a good 5 minutes before I could finally work my legs free.