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chalkfree
Jun 21, 2007, 6:43 PM
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It is generally accepted that the greatest fall factor that can occur is two. As I understand it fall factor is calculated by dividing length of fall by rope out. Thus the concept of letting the rope run that we have from the days of less than ideal ropes.
So what about a bigger than 2 fall? Say for hypothetical example that my partner is ten feet above me and hasn't clipped anything, I'm belaying off my harness, and while I am clipped to the anchor the rope runs from him to my belay device directly. He tells me he is about to pop, and thus I prepare to take some of the slack as he falls shortening his fall. So he falls and while he's dropping I manage to take a foot of rope in, so there are 9 feet of rope between us, when it's over he will have taken a 19 foot fall on 9 feet of rope for a factor 2.111111 fall.
Am I mistaken someplace here?
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roy_hinkley_jr
Jun 21, 2007, 7:05 PM
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Sure, it's possible. Search rec.climbing for extensive discussions.
Also much higher fall factors are easily achieved on via ferrata, which is why special absorbers are required.
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greenketch
Jun 21, 2007, 7:26 PM
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Generally accepted is a good way to put it. It is possible to exceed FF of 2. As noted Via Ferrata goes there often and uses special absorbers to assist with the forces developed.
In trad or sport one will usually be 2 or less but in overhung or cave stuff it is easy to exceed. Especially as you noted when the belayer yards in (or runs) either of these are not "general practice". It is a good idea to seek guidance whenever one leaves the norm as forces outside the norm are sometimes involved.
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papounet
Jun 21, 2007, 8:12 PM
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thus, you may want to leave a lot of slack to the leader until he as put the jesus nut to protect the belay.
Explanation:
the leader is 2 meter above the belay, he falls 4 m onto 2 m of rope =>ff=2
the leader is 2m above with 2 meter slack, he falls 6m onto 4m of rope ff= 1.5
There is nothing that inspires more the leader to put a jesus pro than a good deal of slack, if he complains, tells him it is the newest pedagogy, if he is angry show him the ledge (of course do this on routes with plenty of ledges  )
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cracklover
Jun 21, 2007, 8:37 PM
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It is generally accepted that the sky varies in color from blue, grey, or black.
Yet at sunset, it can be orange or red. Am I mistaken someplace?
GO
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rocknice2
Jun 21, 2007, 11:46 PM
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chalkfree wrote: It is generally accepted that the greatest fall factor that can occur is two. As I understand it fall factor is calculated by dividing length of fall by rope out. Thus the concept of letting the rope run that we have from the days of less than ideal ropes. So what about a bigger than 2 fall? Say for hypothetical example that my partner is ten feet above me and hasn't clipped anything, I'm belaying off my harness, and while I am clipped to the anchor the rope runs from him to my belay device directly. He tells me he is about to pop, and thus I prepare to take some of the slack as he falls shortening his fall. So he falls and while he's dropping I manage to take a foot of rope in, so there are 9 feet of rope between us, when it's over he will have taken a 19 foot fall on 9 feet of rope for a factor 2.111111 fall. Am I mistaken someplace here?
Your right
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curt
Jun 22, 2007, 6:34 AM
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cracklover wrote: It is generally accepted that the sky varies in color from blue, grey, or black. Yet at sunset, it can be orange or red. Am I mistaken someplace? GO
No. I think you got it.
Curt
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