|On 10/12/2011 mikllaw wrote:
>it's LOST 2/3rds (or maybe 7/8ths) of its strength, anyway it lost enough to break.
>The belay was probably a 'hard' catch; as the climber had decided he couldn't
>make the clip and went down to jump off, his belayer proabably took in
>and locked off.
Mike you're barking up the wrong tree. If this was the case, then why did Rob mention in his post that he "felt absolutely no take in the rope as I heard the snap"? I think Rob has already helped clarify what happened in his earlier post, but I'll have a go now too. Otherwise we're going to learn nothing, regardless of how much speculation takes place.
The fact that seems to be getting forgotten was that the positon of the biner. To state the obvious, when a draw is normally attached to a ring, the top biner sits below the ring, flush to the wall. When Rob fell the top biner was not in this position, and it couldn't rotate into this position, due to the ring being too tight to allow gravity to pull it down.
I'll try to explain with more detail what happened. I noticed as Rob was climbing past the 3rd draw that he brushed up against it, resulting in the top biner being flipped upside down (so that it was now sitting _above_ the bolt) and twisted slightly, so that the nose of the biner was in contact with the rock. As Rob moved past the draw the top biner did not fall back into the normal orientation (because the bolt was too tight to allow this to happen), instead stayed upside down. And then, when he fell with the biner in this position, the biner was loaded in a way it was not designed to be loaded ie the nose of the biner was forced back towards the spine of the biner.
I'm no engineer so I don't have the ability to use more descriptive terminology, but I hope that helps clarify.
(NB Although I noticed the biner sitting at an unusual orientation when Rob was climbing above it, I didn't think of alerting him to it, because I never thought that the biner could break if he was to fall. Now I know better!)