The following video is well worth watching. Fortunately everyone survived (though 3 were hospitalised).
- the avalanche is released by the 5th person skiing in the group
- notice that the propagation of the collapse is over a huge area but manifests itself at first as several discrete slabs before eventually the whole slope fails
- 'islands of safety' - during the 2 days I spent with Alain Duclos last autumn we discussed at length the idea of 'Islands of safety' on a slope and how in reality they need to be much bigger and more pronounced than we think they do to offer any real protection. This video is a fine example of that.
**Edit 13 Jan 2015 - the video now appears to have been put on a private setting on Youtube (possibly understandable given some comments on other forums etc), but it is a shame as it is/was very instructive...**