Late 2005 - early 2006: I'll do some research and post them laterNZcaver wrote: I'm not sure - it may have been that incident. When did it happen, and is there a detailed accident report available on-line?
Tubo Longo wrote:Common opinion is that the accident might have been avoided if: 1. the bobbins would have been locked while rigging 2. the brake biner would have been connected to the bobbins's biner instead than to the maillon.
NZcaver wrote: I'm confused by your second point. My understanding is that if you use a separate braking carabiner you should always clip it directly into your maillon - and never into your descender attachment carabiner. Something like this:
As a reference, check out pages 70-72 in "Vertical" (the 3rd, 4th and 5th pages down on this link) - http://www.caves.com/6DESCENT.pdf
Have you been taught different?
Yes and no. The common opinion is, in Europe too, to position the brake biner on the maillon, the way is shown in TSA and Vertical. But is at least a decade (more likely some 15 years) that is well known the possibility that the head of the bobbins MIGHT get into the brake biner in certain situation, i.e. when on rope but with the bobbins not loaded and hanging kinda free and/or slack. If this happen and the caver doesn't realize it BEFORE resuming the rappell (check, check, check...), then is in a free uncontrolled free fall.
The easy solution is to clip the brake biner into the bobbins biner (which btw make kinda unpractical to use a maillon biner for the bobbins, but not a regular oval or delta). Or to buy a Handy brake by Raumer (with a small opening that doesn't allow for the bobbins to fit in) or a Freino.
Unluckily this simple trick is not very well known nor very used. And actually neither Vertical nor the most recent edition of TSA (as far as I remember) mention it.
Cheers -- Renato