In reply to John Blab:
> is there an official accident report or unofficial account that can be provided?
I don't know. I'm quite sure that similar accidents happen so often that it's nothing uncommon.
I try to explain the place as well as I can but it's a bit difficult without a picture (and proper English skills).
The accident happened on 31st around noon. We climbed the same route next day and crossed the spot around 10am when coming down. Weather conditions were pretty much similar on both days.
The crevasse itself was about 2.5 meters wide but still had a weak snow bridge over it. Middle part of the snow bridge was gone so it wasn't difficult to see where the accident had happened. And there were clear signs of the rescue operation inside the crevasse at that spot.
The slope above the crevasse was about 50 degrees but after about two meters and it got less steep and was maybe 35 degrees for the next 40 meters. The slope was snow covered but the snow was more like slush. After some digging it was possible to find fairly solid ice.
When we crossed the same place as a group of two we used ice screw belay. When I crossed the crevasse going up I had a good chance to have closer look of the place. When we came down we jumped over it. By alpine standards the crevasse was deep and wide but still covered with a weak snow bridge. It was quite difficult to see the actual dimensions of the crevasse until you were standing over it. The upper side of the crevasse was about one meter higher than the lower side.
I don't know what exactly happened there on July 31st but there are two obvious scenarios that can result to the accident. Because it was noon, it's quite obvious that they were probably descending.
Scenario 1.
Group of five is using 50m rope with about 8m intervals. This is a normal and a safe thing to do but for some reason they had coils in their hands and moving close to each other. Maybe because the route was very crowded and because of that it was easier to move with coils. Or they were inexperienced and had seen people walking with coils. Maybe they just didn't know where is safe to move with coils and where's not.
The slope above the crevasse is fairly steep and the last few meters are even steeper.
The leader steps through the snow bridge and because of the width of the crevasse there's nothing to slow him down. The second member of the rope is quite close to him with the coils. The crevasse is very deep so the leader doesn't hit the bottom before the rope gets tight.
The leader has taken a long free fall because of the coils and the second is standing on a steep slope. The second has no chance to stop him and he's pulled to the crevasse. The crevasse was very deep. This means that the third member of the team who's standing on the steep slope should be able hold two climbers who are falling in the air. Obviously it's not possible. Domino effect has started.
Scenario 2.
The team doesn't use the full length of the rope. They move very close to each other. Leader steps through the snow bridge and starts a free fall. Other members of the rope have no chance to do anything because everything happens in milliseconds.
When we climbed the route next day and descended over the accident spot there were lots of people going up. Most of them used the techniques mentioned above when they were crossing the very same crevasse.
If you are descending a steep slope and there's a crevasse in front of you, you really should think what to do. If the leader falls, there's a good chance that all the other guys will follow him.
If the rope team has at least four members I'd say it's safe to cross a wide crevasse without a belay. BUT with a tight rope between ALL the members of the team and everyone has an axe ready for the self arrest position. After the leader has crossed the crevasse the situation gets much safer because he's below the crevasse if someone will fall. It's not very likely that he'll pulled uphill to the crevasse.
When we crossed it as a team of two, I made a belay about 30 meters above the crevasse and belayed the leader over the crevasse. Then the leader walked down and I waited that the rope gets tight and jumped over the crevasse.
The sad thing was to see people going up the same spot where two climbers had died 20 hours ago, using very unsafe techniques. And few of the leaders had an UIAGM-badge in their jacket.