Do Screamers Work?

Eric Moss wrote: I'm holding us to a higher standard because we deserve to know what we're dealing with when our lives are on the line. There are answers, but we have to be committed to finding them. It won't be easy, but let's solve this thing for real.

Seriously? You tie into the sharp end of a rope and leave the ground then you already have everything you 'deserve'. It's like saying you 'deserve' to know everything about a route when you attempt a ground up, onsight FA.

Neither you, nor I, nor anyone else 'deserves' anything. None of the tens of thousands of trad FAs over the decades were put up with certain knowledge of any kind about anything other than an intuitive feel for the FAs abilities and sufficient knowledge of their partners and gear to leave the ground with some faith in what might follow.

There is no iPhone app for certainty in climbing and there is no need to 'solve' the riddle of the equalette or screamer. If you can't intuitively sort out what's likely to work for you or not (and how) after you've left terra firma then you probably shouldn't be venturing onto lines where one might want to consider a screamer in the mix.

Crikey! Oh, and no one is running the math on the sharp end of a rope with the possible exception of rgold.

Can you guys pause for like 5min while I go make some popcorn? I don't wanna miss anything, this shit is hilarious.

Healyje wrote: No reason the rope should be running through an atc even in a big fall if you lock it up.

Unless I'm wrong and atc starts to slip at 2kn that is what it makes it more dynamic than a grigri (old style) that starts to slip at 9kn. If it doesn't there is no difference unless ones lets the rope slide through the atc like in the video

JulianG wrote: Unless I'm wrong and atc starts to slip at 2kn that is what it makes it more dynamic than a grigri (old style) that starts to slip at 9kn. If it doesn't there is no difference unless ones lets the rope slide through the atc like in the video

Well, don't know what to tell you other than having held a few decades worth of long and hard falls on an atc, I have yet to have the rope slide through either the device or my hands even once.

JulianG wrote: Unless I'm wrong and atc starts to slip at 2kn that is what it makes it more dynamic than a grigri (old style) that starts to slip at 9kn. If it doesn't there is no difference unless ones lets the rope slide through the atc like in the video

The amount of force any belay device can hold is of an extremely variable nature. Are we talking about a belay bunny with a grip strength of a grasshopper or a 260 lb. viking that spends all day wielding 7' swords and onsighting 5.13s? Are we using a 11mm howser that looks like it was used to tow a semi truck or a brand new 8.5mm redpoint special? Is the device brand new or so worn you could shave in the reflection it produces? Are we going for a hard take on top rope or catching a 120' whip? ect. ect. ect. There are many factors at play that determine the peak force your ATC can withstand before slipping.

True a lot of factors come into play, but the falls I've held have been on all kinds and sizes of ropes and lots of different atcs and I'm for sure not a viking with a death grip.

Healyje wrote: If you can't intuitively sort out what's likely to work for you or not (and how) after you've left terra firma then you probably shouldn't be venturing onto lines where one might want to consider a screamer in the mix.

Physics is often counterintuitive. I choose not to rely solely on intuition. I assume you have done a fair bit of testing in the form of falling on your setup, so you're more knowledgeable. I don't have that luxury and I want to know what will happen before I begin testing with my body.

Eric,
There, of course, is nothing wrong with trying to understand some of the theory behind how a screamer works. However, with all due respect, I think you place too much emphasis on theory and not enough on intuition, or experience, perhaps?Healyje has a wealth of experience in climbing(rope soloing specifically) so I would be inclined to listen to his input/advice when it comes to the use of screamers.

Good climbing!

Is there an actual physicist available to provide answers? Anyone? No, not someone who took a physics class 10 years ago, I mean the real deal. Please help! BTW, something tells me that those concerned about screamer efficacy on this thread are not likely to be taking a giant gear ripping whipper anytime soon. That of course is just my "intuition" talking.

Healyje wrote: Oh, and no one is running the math on the sharp end of a rope with the possible exception of rgold.

Haha. Make that no one then.

Some comments make it sound like "running the math" is an activity done in the absence of any real experience, which might be true for some individuals but certainly doesn't apply to me---I've been climbing for a lot longer than I've been a mathematician.

Some comments also make it sound as if math and experience are in some kind of competition, pitted against each other for the prize of designated oracle. In reality the two are complementary and not in any kind of competition; the results of either one typically inform and cause changes in the conclusions from the other.

Any time you model a real situation, you make simplifying assumptions, otherwise the model would be the real situation and would be as untractable as the real situation. So some sort of error is built into all models, including mathematical ones. On the other hand, experience is powerfully distorted by all kinds of personal perspectives and psychological leanings, and can easily be used to certify conclusions already embraced for other reasons. And formal testing itself, which might seem rigorous, can include confounding variables and unobvious protocols that bias the results.

We are left with a certain irreducible amount of uncertainty, which is part of why these discussions never end. And they shouldn't end, because in spite of the inevitable rehashing, sometimes new perspectives emerge. Of course, those with no patience for such activity, and those who have made up their minds and shut the door to any possibility of altering their positions aren't in any way obligated to participate.

Dylan B. wrote: What you want is an engineer, not a "physicist." Several engineers have commented upthread.

Nope, I want a physicist, engineers are a dime a dozen.

Tim,
Though I haven't taken a "giant whipper" on a screamer I do often use them on multi directional anchors as well as the first bolt or other protection piece above the belay in my rope soloing. Why? Because I trust the opinions of those that have BTDT, not because I did a free body diagram on my anchors! And though I am not a physicist I am a degreed engineer with 20 years experience in the Chemical process industry and I can tell you that theory generally is no substitute for actual experience.

Just two cents worth from a "Dime a dozen engineer.";)

T340 wrote:Healyje has a wealth of experience in climbing(rope soloing specifically) so I would be inclined to listen to his input/advice when it comes to the use of screamers.

It is true that he has a wealth of experience here. And I have no reason to doubt that experience or his knowledge.

However his experience can't really give an assessment on the effectiveness of screamers. If he falls on marginal gear and the gear holds that cannot be used as evidence of a screamers effectiveness.

Personally if you really want answers look at the actual research done.

tim wrote: Nope, I want a physicist, engineers are a dime a dozen.

Do you even know what a physicist is? The core physics theories* involved here barely goes past high school. It certainly does extend beyond a freshmen level physics. Beyond that it is all thermodynamics, relativity, quantum phyics and beyond.

(*Of course in reality it all gets a bit complicated and that is when the physics world merges into the engineering world and engineering experimentation.)

I majored in mathematics and physics in my undergrad at a prestigious University. I suppose you could call me a physicist and a mathematician. (Though I've forgotten plenty of the boring stuff.) No I didn't go into post-grad physics.

patto wrote: It is true that he has a wealth of experience here. And I have no reason to doubt that experience or his knowledge. However his experience can't really give an assessment on the effectiveness of screamers. If he falls on marginal gear and the gear holds that cannot be used as evidence of a screamers effectiveness. Personally if you really want answers look at the actual research done. Do you even know what a physicist is? The core physics theories* involved here barely goes past high school. It certainly does extend beyond a freshmen level physics. Beyond that it is all thermodynamics, relativity, quantum phyics and beyond. (*Of course in reality it all gets a bit complicated and that is when the physics world merges into the engineering world and engineering experimentation.) I majored in mathematics and physics in my undergrad at a prestigious University. I suppose you could call me a physicist and a mathematician. (Though I've forgotten plenty of the boring stuff.) No I didn't go into post-grad physics.

I wouldn't call you a physicist.

Patto,
I don't wish to discount the importance of research into the effectiveness of screamers. I have done some reading about them and find it to be interesting though somewhat inconclusive. I certainly have nothing against the other posters on the thread for wanting to learn more.
Sorry if I gave that impression.

tim wrote: I wouldn't call you a physicist.

Why not? What sort of qualification do you require to call somebody a physicist?

How would that qualification be relevant to this discussion?

(Not that I call myself a physicist ;-) )

T340 wrote:Patto, I don't wish to discount the importance of research into the effectiveness of screamers. I have done some reading about them and find it to be interesting though somewhat inconclusive. I certainly have nothing against the other posters on the thread for wanting to learn more. Sorry if I gave that impression.

No need to apologise. My reading of the research is under most circumstances their effectiveness is minimal. Neither positive or negative. Certainly none off the testing points to their effectiveness being anywhere near their claims.

patto wrote: What sort of qualification do you require to call somebody a physicist? How would that qualification be relevant to this discussion?

I for one would like to see more particle physicists involved in this discussion.

mountainproject.com/v/co-fr…

brenta wrote: I for one would like to see more particle physicists involved in this discussion. mountainproject.com/v/co-fr…

Heheehe.... Okay I'm not a particle physicist!

Schroedinger's Cat a soloist? ;)

patto wrote: I'm not a particle physicist!

Me neither.