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Equalette Not Redundant

Kent Richards · · Unknown Hometown · Joined Jan 2009 · Points: 81
Healyje wrote: I don't believe this is correct and a rope and human in the equation is not a "small dynamic element" but a rather large one. I've held several FF2 falls and I don't believe one side of an equalette blowing wouldn't have made a significant difference in any of those cases other than adding to the beating. In all three cases the anchor was bomb and I would further suspect anyone having died from an anchor failure died on an anchor which was compromised from the beginning. From where I sit the message isn't about equalette extension, it's about not using / building shit anchors.
I agree with part of this.

However, in the book they make blanket statements like "True shock loading cannot occur," but then qualify that statement in a dispersed and circuitous manner that someone could easily miss.

Maybe extension isn't a problem if it's relatively small, the anchor pieces are bomber, and there's enough dynamic in the system (I'll leave it to the engineers).

But, it appears that more than one newbie has come away from the book having missed the caveats and thinking simply that "extension isn't really a problem".

If they then take that generalization and in their noobness combine a sliding-X in a trad anchor with some less-than-bomber pieces [noobs are more likely to place sub-optimal pieces] and clip in with pick-your-static-tether instead of the rope [noobs are more likely to use a static tether], then they've set themselves up for a much higher chance of catastrophic anchor failure.

Yeah, for sure, the goal is to build bomber anchors. But in the bigger picture of risk mitigation, avoiding extension is a strategy for mitigating the risks of sub-optimal pro and accidentally clipping into the anchor with a static tether.
patto · · Unknown Hometown · Joined Jul 2012 · Points: 25

I think you sum it up well Kent.

Kent Richards wrote:Maybe extension isn't a problem if it's relatively small, the anchor pieces are bomber, and there's enough dynamic in the system (I'll leave it to the engineers).
As far as forces go, I would go as far as saying it isn't a problem at all in such circumstances. Hey you can just use the climbing rope and almost all these issues go away and it is super strong and dynamic.

But i still avoid extension because as a belayer i don't want to be pulled off my stance. (Not that I've EVER had a piece blow on me.)
rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526

I got into Long's book because I had been arguing for years that really simple rope physics made it clear that unequal-length cordalette arms would result in unequal loads, and so the "equalization" people kept talking about was unattainable in most situations, even if the rigging was otherwise "ideal." Long and Jim Sterling then did some load tests that confirmed this, and John wanted to include the description I had posted of how the inequality arises.

I have to admit that John sent me a manuscript, which I read. But I did not at the time notice the problem with the extension testing. This later put me in the awkward position of saying the testing protocol fails to replicate some practical belay circumstances, given that I had the chance to suggest the correction to John before publication and really should have caught the problem then.

But I didn't...

Healyje · · PDX · Joined Jan 2006 · Points: 422

I would also add to the discussion that if you have any doubts about your anchor - and it's not a hanging belay - then those are the situations where the lost art and craft of stancing comes into play - as in belaying without loading the anchor even when catching long or hard falls or attempting to minimally loading the anchor.

bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065

has anyone figured out a way to make their pretied equalette work in VERTICAL cracks where each piece is ~a foot apart and which distributes the load EQUALLY between all 3 pieces? ... not to mention NOT having to tie additional knots or cloves?

and having one arm to one piece and the other arm cloved to 2 pieces does NOT distribute it equally .. it gives roughly a 50/25/25 distribution in theory as in the setup below



until it does the "discussion" of the equalette is basically limited to bolted anchors where its irrelevant, and to horizontal ones (and even then you wont get equal distribution with 3 pieces) ... its not an "all inclusive" anchor system as youll need to make it more complex or retie it to handle vertical cracks

the cordelette style anchors, whatever its "flaws" can be used with any material on any anchor configuration if you have enough length

KISS

;)
Brian L. · · Unknown Hometown · Joined Feb 2016 · Points: 90
bearbreeder wrote:which distributes the load EQUALLY between all 3 pieces?
I don't know about the general climbing community, but my own idea of equalization isn't one where the load is shared equally between all the pieces (meaning, in a three piece anchor each piece shares 1/3 of the total load). This is basically impossible to achieve because of how physics works.

My idea of equalization is where each piece is loaded, and that load is according to the physics of the set up. Which depends on where the load is applied, what direction, and the angles of the legs of the anchor.

An equalizing anchor is supposed to ensure there is always some amount of load distribution, regardless of the direction of pull. Something like a traditional Cordlette can easily unload all but one leg if the direction of pull is set up wrong, or changes (or the legs aren't tied exactly evenly, which is very easy to do). This potentially results in cascade failure of the anchor pieces (like I believe is suspected in a double fatality at Tahquitz Rocks in 2003). This is basically the reason these equalizing anchors came into existence.

The only way to equally load three piece that I can imagine off the top of my head is having three pieces set up like a triangle each equal distance from each other (forming the points of an equilateral triangle), having the force vector running normal to the plane of the triangle, and through the center, and having the legs of the anchor all being equal lengths. Basically impossible to achieve in real life.
patto · · Unknown Hometown · Joined Jul 2012 · Points: 25
Brian L. wrote: I don't know about the general climbing community, but my own idea of equalization isn't one where the load is shared equally between all the pieces.
It seems that some (including to some extent John Long) did not share the clarity of this view.
Greg D · · Here · Joined Apr 2006 · Points: 883
bearbreeder wrote: .. it gives roughly a 50/25/25 distribution in theory as in the setup below until it does the "discussion" of the equalette ...
That distribution is fine and adequate. And better than a cordalette could do. I'm not sure what your point is.

In your diagram it is quite possible that the left piece would get the closed loop. No eight needed. And possibly the far right piece too. So only one clove needed. And since this would typically be employed in multi pitch one can do a quick setup. Put follower on belay. Fine tune it while follower is climbing since it is only subject to top rope loads at this point.
rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526

My sense of the overall testing results we've heard about is that no matter what rigging system you use, the chances are that one piece will get 50% (or more) of the total load. This is a result, not only of the effects of unequal arm lengths, but also all the random variations in arm-loading that result from the impossibility of correctly proportioning the arms and the fact that knot tightening could undo correct proportions even if they had been achieved.

This being the case, I can't see any reason to use a pre-tied equalette for any kind of three-piece anchor (and as bearbreeder says, with two modern bolts there is no need for any load-distributing niceties).

This leaves the case of two-piece trad anchors. In the US, this seems to be considered perhaps substandard, but not so in the UK and Europe where two is the norm. Two-piece anchors for time and equipment stressed alpine climbing are pretty standard worldwide I think. I still wouldn't bother with an equalette for these situations, since it is far from clear that, in the field, it distributes any better than fixed-arm rigging and I know that there are admittedly rare extreme circumstances in which the extension problem will be bad.

So that leaves no reason for me to ever use a pre-tied equalette. Others may have reach different conclusions.

Ted Pinson · · Chicago, IL · Joined Jul 2014 · Points: 252
Greg D wrote: Put follower on belay. Fine tune it while follower is climbing since it is only subject to top rope loads at this point.
Wait...what?
patto · · Unknown Hometown · Joined Jul 2012 · Points: 25
rgold wrote:Two-piece anchors for time and equipment stressed alpine climbing are pretty standard worldwide I think.
And alpine anchors can often be on far more marginal protection...

At the start of this year, I lost two people very close to me due to what was reportedly an anchor failure. An extremely well respected, experience and skilled alpine guide. Unfortunately it seems the anchor available wasn't capable of holding the weight of a falling second.

Ted Pinson wrote: Wait...what?
Meh. The realities of fast climbing. Clip into a couple solid pieces and get your partner on belay. Nothing wrong with fine tuning your anchor after you've started belaying.

Ever done a meat belay? Zero pieces just a good stance. Perfectly equalised! :-p
rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526
patto wrote: At the start of this year, I lost two people very close to me due to what was reportedly an anchor failure. An extremely well respected, experience and skilled alpine guide. Unfortunately it seems the anchor available wasn't capable of holding the weight of a falling second.
Wow, Patto, I'm so sorry to hear that.

I'm sad to say that this fits into a long-term pattern for me, which is I hear about a total catastrophic anchor failure about once every ten years. Since I've been climbing for almost 60 years, the count is up to about 6.
Brian L. · · Unknown Hometown · Joined Feb 2016 · Points: 90

Guess another thing to note is that 50/25/25 distribution isn't really correct either. Like I said, it depends on the geometry.

For instance, one test using that diagram as a guide set up an equalette where the static load was distributed ~ 53/10/37

And while we're at it, there are load cases where the anchor shown will unload a piece. An equalitette really only ensures at least TWO pieces receive a load.

rgold wrote:and I know that there are admittedly rare extreme circumstances in which the extension problem will be bad.
Really, it seems like it's a pick your poison situation. Which extreme case are you worried about: the potential for a problem from extension, or the potential for cascade failure from single point loading.

Not that this is really evidence one way or another, but it's been 10 years since the book came out. Does anyone know of any accidents where extension of one of these types of anchors has been suspected to be the cause?
bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065
Greg D wrote: That distribution is fine and adequate. And better than a cordalette could do. I'm not sure what your point is. In your diagram it is quite possible that the left piece would get the closed loop. No eight needed. And possibly the far right piece too. So only one clove needed. And since this would typically be employed in multi pitch one can do a quick setup. Put follower on belay. Fine tune it while follower is climbing since it is only subject to top rope loads at this point.
Please upload a photo of a PRETIED equalette with a 3 VERTICAL pieces each 12"apart ... Where the "equalizing" portion is in the centre pretied and ONLY one extra clove is needed ...

The point is in real life anchors in VERTICAL cracks youll need additional work to make a PRETIED equalette work .... Or re/untie it

And that with ODD number of anchor points youll never get an equal distribution between the pieces

In a 3 piece anchor one piece will get roughly 50%+ of the load and in a VERTICAL crack she closest piece will see most of the load anyways just like a cordelette

One can use an equalette if they want but the "load distribution" advantage on 3 piece anchors is marginal over other basic aetups

;)
patto · · Unknown Hometown · Joined Jul 2012 · Points: 25
rgold wrote:Wow, Patto, I'm so sorry to hear that.
Thanks...

rgold wrote:I'm sad to say that this fits into a long-term pattern for me, which is I hear about a total catastrophic anchor failure about once every ten years. Since I've been climbing for almost 60 years, the count is up to about 6.
Just to be clear this was ice/snow not rock. The media reports didn't report it as an anchor failure, and I'm still have not confirmed all the details. I'll wait for a coronial report. It could be the case that there was no anchor at all, that is what I initially presumed, but information I recieved suggested otherwise. (I have PM'd you a link to one media report.)
rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526
Brian L. wrote: Really, it seems like it's a pick your poison situation. Which extreme case are you worried about: the potential for a problem from extension, or the potential for cascade failure from single point loading.
This is a good point and refers to a property of the standard 3-point fixed-arm rigging that doesn't seem to be particularly well-known: if the three points are more or less horizontally aligned and either of the outer arms fails, then the entire load goes to the middle arm (with no contribution from the side arm that didn't fail) and if the middle arm fails, then the entire load goes to the remaining side arm. In other words, once an outer arm fails, there is no more load-sharing.

The reports of three distinct "thunks" heard by some witnesses to the Tahquitz accident is consistent with this type of cascade failure.

One possible take-away: two good pieces is arguably better than two good and one questionable piece if the questionable piece is rigged on an outer arm. But in this case using an equalette on the two good pieces with the third arm going to the questionable piece would mitigate the cascade potential. You could also tie your cordalette or arrange your rope-anchor rigging to share the load among the two good pieces and situate the third as a backup.

As for choosing a poison, the cascade failure doesn't elevate the load to the remaining pieces, but the extension failure can, and depending on the length of the tie-in the elevation could be quite significant. So my choice is the cascade failure poison, informed by the consideration of not weakening a good two-piece anchor with a questionable third piece on an outer arm.
bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065
Equalette vertical spacing

Equalette 2

Cordelette vertical spacing

Cordellete 1:1:2

Here you can see how a PRETIED equalette requires more faff for pieces in a VERTICAL configuration

As a note the 1:1:2 cordellete bottom pic config allows you to maximize the load on your strongest piece as much as possible

With at least 2 clove hitchs and a double fishy on a cord equalette .... Anyone here think they can really predict the actual load distribution in reality on a vertical 3 piece anchor?

;)
bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065

As a note yes an equalette has 2 biners in the sliding portion ... Im just to lazy today to put them in =P

So horinzontally spaced anchors is where the equalette should be perfect eh?

Heres a few issues with your standard length (240 cm sling) pretied equalette

On a 2 piece say you want to shorten the anchor so its not too long, ie the masterpoint not dangling below you... You can see how additional cloves are now needed

2 piece horizontal

2 pice shortened

Now a 3 piece horizontal should be easy right?

Well you can see the issue below if you dont use an extra knot to centre the "sliding X" portion

3 piece horizontal uncentered

Centered with extra hitch

One advantage of cordellete style anchors is that you have FOUR clip in points, which is really useful in a part of 3, crowded anchors, or for self rescue/hauling

Cordellette clip in points

The point isnt that an equalette is "bad" but that youll often need ADDITIONAL knots or hitches to make it work

And that the loading on 3 piece anchors still isnt "equal"

;)

Brian L. · · Unknown Hometown · Joined Feb 2016 · Points: 90
bearbreeder wrote: ....stuff....
Yeah, but really you should just use the rope.

;)
David Coley · · UK · Joined Oct 2013 · Points: 70
rgold wrote:This leaves the case of two-piece trad anchors. In the US, this seems to be considered perhaps substandard, but not so in the UK and Europe where two is the norm.
Hi, except when the pieces are bomber, I'd say 3 piece was the norm in the UK. But remember, it is still uncommon to use a cordelette in the UK, so even with two pieces there would be a nice load of rope involved. Direct belays are also not the norm, although increasingly fashionable.
Guideline #1: Don't be a jerk.

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