Falls on pro - lessons learned?

eli poss wrote:

In a very short, high factor fall it is possible for other factors to account a small, but statically significant portion of the total energy dissipation. Keep in mind, this is the exception, not the rule. But it explains why a 30' FF2 will hurt a whole lot more than a 1' FF2

Yup, agreed.

Xam wrote:

I am with you that equating a short factor 2 fall on a PAS to longer factor 2s is disingenuous.  The total energies in a very short factor 2 fall are low enough that other energy absorption mechanisms are enough to reduce the total force experienced by the climber.  

However, I disagree with the statement in bold above.  Simple theory does say that the forces (T) experienced by the climber should be the same for falls over different lengths but of the same fall factor.  See below.  Note r=H/L is fall factor.  If you disagree, please point out the flaw in the paper at http://4sport.ua/_upl/2/1404/StandardEqn.pdf

Well, first, let's circle back to what you said above. Fall factor 2 at 2 feet of rope is clearly, empirically, not = to a fall factor 2 with 200 feet of rope. The variable that would be vastly different is the velocity of the falling body and, therefore, the energy to be absorbed. Given that a fall factor 2 is the worst case scenario we're talking about variations in how bad "worst" means. 

The other place I think this goes off the rails is if you're pushing the theory in the other direction. Sure, you could have a 200 foot fall in a system with 800 feet in the rope and it'd be "theoretically" trivial. Show me the real world scenario for this, though.

Fact is that most climbing falls are between a couple feet and, maybe 20. A 40 footer is a HUGE fall for most of us. As stated above, "Fall factor" is a theory for comparing the realtive impact on gear and bodies of falls of similar length. I'll gladly take a fall factor .5 over a 2 every day, just like you will, but there are real world, practical limits to how those play out.

While I appreciate your point, I still think you either misunderstand or are misrepresenting what fall factor illustrates and the difference between energy and force in a clean fall. Thank you for the response, though.

I have learned that if the rock is bad, place more gear. It is surprising what will hold. I took a 20 foot whipper from about 8 feet above my last piece when a block i pulled on flew out. My partner cleaned the gear (which did not pull out) and exclaimed to me and the other team member, "I can't believe you were climbing on that dog sh*t!"...Also, cam placements in flares are likely to pull out if falllen on.....Additionally it is good for a belayer to keep an eye on the climber in unfamiliar territory, as large, seemingly fixed boulders can in reality be perched precariously and fall towards the belayer when being pulled over for the first time. There is nothing quite like the sight of a golf cart size rock hurtling towards you to make you glad that you weren't looking at the ground or other features of the scenery and missing the chance to jump out of the way ( and discovering when the dust settled that the leader was still on belay, and none of the gear pulled, and the rope was still intact between the belay device and the leader despite being severed at the ground.)

Take the whip!!

I once took a short fall on a purple alien that somehow ended up twisted in 45 degrees axially the crack, with only one lobe on each side of the stem on rock. It held. Looking up, I couldnt believe what I was hanging on.

AndrewArroz wrote:

The other place I think this goes off the rails is if you're pushing the theory in the other direction. Sure, you could have a 200 foot fall in a system with 800 feet in the rope and it'd be "theoretically" trivial. Show me the real world scenario for this, though.

Bunge jumping. Works on the same principal. The only difference is the dynamic property of the rope they use. Bunge jumping is actually worse. It's a factor 1 fall.

What you're missing is that as the fall distance increases, for the same fall factor, so does the energy absorption capability of the rope - in equal portions with the fall energy.

In short falls, other factors besides the rope have a greater impact on the energy absorbing characteristics of the system. However, in long falls with high energy, those other factors (which are constant, not variable) become insignificant compared to the magnitude of rope's characteristics (which is variable based on length of rope in the system).

The difference between the short fall, and a long fall, is how far the rope stretches.

Brian L. wrote:

Bunge jumping. Works on the same principal. The only difference is the dynamic property of the rope they use. Bunge jumping is actually worse. It's a factor 1 fall.

What you're missing is that the as the fall distance increases, for the same fall factor, so does the energy absorption capability of the rope - in equal portions with the fall energy.

In short falls, other factors besides the rope have a greater impact on the energy absorbing characteristics of the system. However, in long falls with high energy, those other factors (which are constant, not variable) become insignificant compared to the magnitude of rope's characteristics (which is variable based on length of rope in the system).

The difference between the short fall, and a long fall, is how far the rope stretches.

This.

But I suspect some will continue to not get it, no matter how many different ways it is explained.

My partner once took a 110' fall. Got to the bottom of all the rope stretch and then got a nasty scratch on his thumb on the way back up - otherwise uninjured, said the fall was really soft.

Healyje wrote:

My partner once took a 110' fall. Got to the bottom of all the rope stretch and then got a nasty scratch on his thumb on the way back up - otherwise uninjured, said the fall was really soft.

Was it terrifying during the execution?

Xam wrote:

While I appreciate your point, I still think you either misunderstand or are misrepresenting what fall factor illustrates and the difference between energy and force in a clean fall. Thank you for the response, though.

I appreciate your point, too. What I think is getting lost is that people seem to believe that "fall factor" is the end all of describing how serious a fall is. But it doesn't describe what most people think it does. Point is that FF is to describe the varying dynamics of similar falls based on the length of dynamic rope in the system. It DOES NOT say that a 1 foot FF2 is identical to a 10 foot FF or a 100 foot FF2 in its effects on the gear or person involved.

AndrewArroz wrote:

It DOES NOT say that a 1 foot FF2 is identical to a 10 foot FF or a 100 foot FF2 in its effects on the gear or person involved.

Except that it does.  Please see equation (8) in the snippet that I posted from RGold in the previous post.  The force (T) on the climber and top piece of gear (~2T) is the same in all three cases, assuming the same climber and rope and clean falls.  

I don't know how to say it any clearer.  While there are additional higher order dynamics not accounted for in the simple theory, these are the exception, not the rule.

AndrewArroz wrote:

I appreciate your point, too. What I think is getting lost is that people seem to believe that "fall factor" is the end all of describing how serious a fall is. But it doesn't describe what most people think it does. Point is that FF is to describe the varying dynamics of similar falls based on the length of dynamic rope in the system. It DOES NOT say that a 1 foot FF2 is identical to a 10 foot FF or a 100 foot FF2 in its effects on the gear or person involved.

What effects are you referring to? If you're referring to the resulting force of the fall: it does.

You seem to be hung up on the idea that higher velocity (from a longer fall)= higher force. But that isn't the case. Your net acceleration determines the force. We all learned F=m*a in high school physics. In the case of being caught by the rope, the dynamic properties of the rope determine that. The rope slows you at the same rate regardless of it you fell 10ft or 100ft.

Think of it this way: if a car is traveling at 60MPH, and I hit the brakes slowing it at a rate of 1MPH/s, the car comes to a stop in 60 seconds. 

If the car was going 100MPH, and I hit the brake's the same amount, I feel the same force, but it takes 100 seconds to stop, and I go farther before I do.

Bill Czajkowski wrote:

Was it terrifying during the execution?

He was on a route that led up to a not wide roof below a wide headwall which the route went around to the right. Not knowing that and us being heavily roof-inclined, he does the irreversible roof moves and ends up marooned on small holds on a relatively blank headwall. He was up there for quite a while trying to work out downclimbing or going up, but finally just stopped, paused, turned sideways, and then pushed off. Only time I ever heard a low guttural moan out of him. I personally would have been a losing it, crying, screaming mimi by that point myself, but he was always a far burlier human than myself.

Brian L. wrote:

What effects are you referring to? If you're referring to the resulting force of the fall: it does.

You seem to be hung up on the idea that higher velocity (from a longer fall)= higher force. But that isn't the case. Your net acceleration determines the force. We all learned F=m*a in high school physics. In the case of being caught by the rope, the dynamic properties of the rope determine that. The rope slows you at the same rate regardless of it you fell 10ft or 100ft.

Think of it this way: if a car is traveling at 60MPH, and I hit the brakes slowing it at a rate of 1MPH/s, the car comes to a stop in 60 seconds. 

If the car was going 100MPH, and I hit the brake's the same amount, I feel the same force, but it takes 100 seconds to stop, and I go farther before I do.

Thanks for actually making my point. You're stuck on theory. I'm talking about the real world. If you're travelling 60 MPH and slam on the brakes because a moose stepped out in front of you, you JUST miss the moose. Same car, traveling 100 MPH, you and the moose both die and your car is totalled. Likewise, you can claim all day long that the rope slows you at the same rate regardless if you fell 10 feet or 100 feet and you would be right about the rate of slowing. But I CHALLENGE you to show you a real-world climbing situation in which a person falls 100 feet with adequate (say 500 feet) of rope out to absorb the impact just like a 10-foot fall with 50 feet of rope out. It DOES NOT EXIST. Equivalent on paper does not = same in the real world. 

Look, I've bungie jumped out of a hot air balloon on a 150 foot cord that stretched a HUGE amount. I understand how dynamic absorption of a fall works.

This is a thread about "falls on pro, lessons learned." An important lesson to learn is not to run yourself out because the more you're run out the more impact from your fall on the system and gear. And the farther you fall with less rope out the worse that is (the FF argument) but it distracts from the practical matter to tell a beginning trad climber that a 20 foot fall is "the same" as a 2 foot fall if the FF is the same. That would be terrible advice, for a lot of other reasons. 

If you are saying that longer falls are worse because you have higher chance of hitting a moose on the way down, you will get no disagreement from me...

I'm always surprised to see how many climbers don't orient gear downward; specifically SLCDs.  Sure there's times when non-downward orientation is applicable.  I'm not referring to those.

The point is: orient your gear correctly, given the application.

climbing friend,

ho ho, I am seeing I do believe based on these postings there is not much happening in your lives in term of the activity of sexual type, ha!!!

AndrewArroz wrote:

Thanks for actually making my point. You're stuck on theory. I'm talking about the real world.

What "theory" do you keep referring to?  We're talking about a model.  Based on very well understood physics.  Not a theory.

 If you're travelling 60 MPH and slam on the brakes because a moose stepped out in front of you, you JUST miss the moose. Same car, traveling 100 MPH, you and the moose both die and your car is totalled. Likewise, you can claim all day long that the rope slows you at the same rate regardless if you fell 10 feet or 100 feet and you would be right about the rate of slowing. But I CHALLENGE you to show you a real-world climbing situation in which a person falls 100 feet with adequate (say 500 feet) of rope out to absorb the impact just like a 10-foot fall with 50 feet of rope out. It DOES NOT EXIST. Equivalent on paper does not = same in the real world. 

Um....how about a 20 ft fall with 100 ft of rope out?  I'm really not sure what you're getting at here.

the farther you fall with less rope out the worse that is (the FF argument) but it distracts from the practical matter to tell a beginning trad climber that a 20 foot fall is "the same" as a 2 foot fall if the FF is the same. That would be terrible advice, for a lot of other reasons. 

It is terrible advice to claim that there is some set of magical second-order effects that invalidates the fall factor model for anything but the most extreme circumstances.  Helping a beginning trad leader (or belayer!) understand that, all things being equal, she is better off taking a 40 ft FF0.5 whipper than a 4 ft FF0.9 drop on a questionable piece of protection is extremely valuable.  This is not obvious or intuitive to most people, so being able to accept the math and understand the consequences of different fall scenarios is important.

Look, nobody is claiming that all FFx falls are "equal".  Depending on the terrain, longer falls can obviously be more dangerous, and nobody is saying otherwise.  But recognizing that fall factor is the key parameter that defines the peak force acting on the climber, the belayer, and the system is pretty damn important.

We've hashed out the fall factor model enough for one thread. People who still don't understand it or don't  believe by now aren't going to suddenly get out from another few pages of explaining. If they wanna think the earth is flat then they're gonna think the earth is flat.

Back to the original topic, regardless of what it does to fall factor, additional slack may cause you to hit a ledge or cheese grater on the way down, especially on easy beginner leads. Don't give an excessively loose belay