Safe run-out analysis

[slothrop]

Pfft... "rangefinder" cams. If you don't carry these two essentials, you're practically free-soloing:

 

The Impulse Laser Rangefinder (with optional tilt sensor)

 

The Dyer 651 series electronic ID calipers

 

Designed to "Measure all types of internal grooves that are hard to reach":

 

Don't be sketchy! Mountaineers Approved !

[chriss]

 

His figure 12 results of M (dynamic modulus) don't make sense. They are all to high. Like ~ 40-50% to high.

 

Check them using manufacturers test fall data.

 

 

chris

[catbirdseat]

The take home message for me is what I've always known: the greatest danger is when you first leave the belay. The higher you climb and the more gear you place, the safer you will become. Build a SRENE anchor, get a piece in right away and place your gear close at first until you get some rope out.

[dryad]

Thank you CBS for those brilliant insights.

[catbirdseat]

[Dru]

The take home message for me is what I've always known: the greatest danger is when you first leave the belay. The higher you climb and the more gear you place, the safer you will become. Build a SRENE anchor, get a piece in right away and place your gear close at first until you get some rope out.

 

Free solo, then you don't have to worry about fall factor.

[chriss]

 

The report leads to believe that falling on the belay anchor is safer than falling on the lead protection. The lead protection suffers from the "pulley" effect and has forces exerted on it greater than produced in the fall alone. So taking a fall factor of 1 or more on to the belay anchor generates less force on the anchor.

 

That is why I give the report no credibility.

 

 

chris

[scott_harpell]

How do you take a factor 1 fall ON the anchor?

[chriss]

 

You have 50m of rope, you fall off at the anchor and fall 50m. 50/50=1 Basically no belay at all. So any "lead" fall would have a fall factor between 1 and 2, unless you climbed down and fell.

 

This would be stupid to do, but it allows for the lowest force on the gear. It would always use the full length of rope to absorb the fall and no "lead" protection (to suffer "pulley" and friction effects). This is why the report and a strictly analytical approach is not always best.

 

chris

[scott_harpell]

Exactly... how do you do that? You would have to be the most insanely stupid person on this Earth to do that.

[MATT_B]

I saw it happen once. A guy jugged a pitch and never tied in short. When he got to the anchors he must have taken his ascenders off and never tied into the anchor. Couple minutes later I hear a screem and see the guy flying down the pitch below. Thought he was going to crater but stopped right next to the anchors one pich below. At least he was tied into the end of the rope. That would be a fall factor 1 onto his anchors. Although it wasn't vertical (second or third pitch of the free blast) and he lost some skin slowing him down.

[scott_harpell]

You would have to be the most insanely stupid person on this Earth to do that.

[catbirdseat]

I saw it happen once. A guy jugged a pitch and never tied in short. When he got to the anchors he must have taken his ascenders off and never tied into the anchor. Couple minutes later I hear a screem and see the guy flying down the pitch below. Thought he was going to crater but stopped right next to the anchors one pich below. At least he was tied into the end of the rope. That would be a fall factor 1 onto his anchors. Although it wasn't vertical (second or third pitch of the free blast) and he lost some skin slowing him down.

Sounds like bungee jumping. Yikes.