Alex

I give up. this article does a better job than I can at explaining all this http://www.uoregon.edu/~opp/climbing/forcesinleadfalls.pdf Cheers

+belayer force +impact force = -belayer force - impact force =0

You are right, the sum of the forces in x, y, and z planes must be zero, or some part of the system must be in motion. yay! What you are saying is that the force of the falling leader is different if the rope runs through the anchor. The orientation of the rope has nothing to do with the mass of the climber and the acceleration of gravity. Yes. and it is, different. If you want to get down to nitty gritty, the force on the leader will be almost identical if there was a draw or not. But who cares, thats not the point!!! The points are this: 1) Every force has equal and opposite force. This addresses Forests argument that the force is multiplied when another component enters the system. You dont get systems where there is 1000 pounds on the anchor, 1000 pounds on the belayer, AND 1000 pounds on the leader... +1000+1000-1000 = 1000.....not 0. Thats not correct. 2) And if you are belaying someone, it only makes sense to put a draw on the belay if that someone is maybe gonna fall, to be pulled INTO the belay rather than away from it. The force on YOU (effectively the anchor) will be the same if you do or if you dont. Why not prevent getting whipped around and down, shockloading the anchor maybe, and just have the anchor take the load directly? This is what the point is. ...you know that the force required to hold the c-pulley in a static position is 1/2 the weight (in newtons or pounds-force) of the victim (ignoring friction). Yes. but this is not what you said earlier. Lets revisit your first post: It is worth noting that running the rope through the belay can effectively double the impact force on the belay in such a situation. If the belay failed you would end up with a much bigger problem than a tib-fib fracture. Sometimes I run the rope through the belay, and sometimes not. It depends on my opinion about the strength of the anchor system and the potential for a factor-2 fall. This contradicts what you are saying now, in agreement that summing all forces is zero. It does not doulble the impact force. The force is the same on the anchor, for the same fall. There is only ONE thing in this entire system generating force. The falling leader. The force of the falling leader for the same fall (thats a fall of the same distance!!) in ALL systems is the same. Agree? Lets call it 1060. In the system where he falls directly against the achor, scenario 1, the force against the anchor and the Leader are equal and opposite. +1060 and -1060. Now the second scenario is almost the same, but there is a draw on the anchor, a few feet away from thebelayer. The fall is the same distance (maybe a few inches shorter because of the draw, but as we say, who cares?). The force on the draw, and thus the anchor is STILL 1060, or thereabouts. Agree? Technically, the force is now split between the belayer and the leader against the anchor, but realistically this is proportional to the amount of rope from the belayer to the draw, compared to the amount of rope from the leader to the draw. So the longer the fall, the more skewed to one side this is. The only thing different is the belayer is not getting whipped around into the direction of the fall, rather just getting slammed into the rock of ice by the belay. Lets look at two complete equations: Force T is the force applied to the anchor after joe has tied off to it and bungie jumped 100 feet with 100 feet of rope. OK? So our forces look like Anchor: +T joe: 100/100(-T) +T = -100/100T = 0 Now second. Force T is for joe who just took a ~100 foot fall 50 feet above the belay. Jut Sally is belaying, 3 feet from the belay, with a draw: Anchor: +T joe: 97/100(-T) sally: 3/100(-T) but here we have +T = -97/100T - 3/100T = 0. right? The forces here on sally are comparatively negligible, but sally isnt getting whipped into the direction of the fall. There is no Tib Fib. There is no "doubling" of the forces on the anchor. Similarly, when you top rope someone from above, do you belay the second directly from your device? Or through a draw on the anchor? Anyone who has held a fall of a second knows that getting pulled in the direction of the climber is undesirealble. You want to be pulled in the direction of the anchor. The force calcs here in this situation are no different. The (body-weight)force is against the anchor. Hope that helps. Alex

iain, yes, completely agree with the drawing. Its exactly what I have been saying. +10N +10N -20N = 0. Please read my post. All force has equal and opposite force. The sum of it all is 0. Alex

iain, you are correct in both cases. But you left something out. Wouldn't you agree if you replaced an ideal pulley for the quickdraw and you had a climber with force T falling and a secured belay on the other side that there would be a force of 2T on the pro? so the force on the leader is +T, and the force on the anchor is -2T (right?) so whats the force on the belayer? +T. So the equation becomes +T+T-2T = 0 I'm not sure I see where you're going, whether you agree or disagree with this. If you just tied the rope to the draw, you would only have T on the pro. yes, +T on the leader and -T on the pro. +T-T=0. Alex

no option a: falling straight onto the belay. when the climber hits the bottom, they put a force on the rope of, say, 1000 pounds. the anchor must therefore resist 1000 pounds to balance out the 1000 pounds of tension in the rope. I absolutely agree. option b: falling on a quickdraw: same fall, rope from climber to QD had same 1000 pounds of tension; no, it doenst but to keep it from slipping, the rope from the QD to the belay must also have 1000 pounds in it, more or less in the same direction of pull (assuming both belayer and fallen climber are below the anchor). no, it doesnt. therefore, the QD has 2000 pounds of tension in it, because it is being pulled down by 2 lengths of rope, each with 1000 pounds. the anchor must therefore support double the weight. no, it doesnt. The anchor will always have 1000 pounds applied to it in this situation. It's the forces against the other components of the system you must now consider. In the first scenario, there are 2 components to the system, the anchor and the leader (since our belayer is directly in line with the anchor->leader force vector and therefore doesnt have any role in the force calculations). We all agree on this. In the second scenario, there are 3 components to the sytem. The anchor, and the force on it, is unchanged. Its still the SAME FALL. The other components in the system change though. This is precisely what Lorens diagram above shows, actually. If you keep adding components, the force on EACH component will go down. Think about it. With 2 components, the force exerted on EACH is less than with 1, in the first scenario. How about if you now added 2 ropes to the belayer and 2 draws. The anchor STILL takes 1000 pounds, but now each Leader - draw takes half the force that it did before, and each belayer to draw also. There are now 4 components. Does that mean there are now 4000 pounds of force?? No, it means that each component now only has to deal with 200, 300 or so, whatever adds up to 1000. This is because for every force there is an equal and opposite force. This is a fundamental law in Physics (Newtonian mechanics). If the force on your anchor is 1000 pounds as you state, the opposite force MUST BE 1000 pounds combined on the belayer and leader. Force vectors are addative here, the sum of all forces MUST be 0. Lorens diagram bears this out. This MIGHT transate to more on each component with some force vectors, which is why you tend to equalize anchors with less than 60 degree angles, as you hint at Forest, for example, but I dont usually do that much math to figure out how much more. However, you cannot magically conjure up another couple thousand pounds of force. It makes intuitive sense. This is one reason you climb on twin ropes, and each rope takes some of the falls force. This is why its BETTER to have a piece between you and the anchor when you fall. And better to have a piece on the anchor, even if there is nothing else between you and leader. Alex

Loren, your picture makes sense to me, but your explaination does not. From this picture, its obvious that the force on the anchor would be 1160 daN regardless of what the forces on the climbers are. By adding a draw, the force is now split between the climbers (good!), rather than being exerted completely on the leader(bad!) and the leader's belay tie in, as it was in the case described above on Louise Falls. Think about it. In your picture the belayer only has to hold 700 daN of force through the ATC, rather than 1160. This is good. The leader only takes 460 Newtons on his tie in. But the anchor will ALWAYS take 1160. There is no question. So by adding a draw you are lessening the forces on your own belay loop and belay device, and on the leader, but otherwise the forces are always going to be the same. Alex

how does that work? the factor 2 load is directly against the belay, whether you feed the rope through the belay or not..? Isnt the load the same? Its not like your body can compensate for it, your harness is made of static webbing.

fern, I am not sure? I suppose that if you were to wander around up there, you might stumble upon some unexploded ordinance, though. The routes look great, easily as nice as anything in the rockies. There is no snow right now at Rogers Pass, and with no snow there is no av hazard, so might be worth the risk of trying out some of these lines. The approaches look to be about 30 min from the highway. You guys know if there is a guidebook to this or the Revelstoke area? Jo Jo doesnt cover it and I kinda wonder why, its pretty close to Golden! Alex

Its not BC, but we have no Canadian Rockies section... I just read an account of Sean D's attempt on Greewood Locke in winter on the N Face of Temple. Temple is pretty impressive, I always like looking up there and wondering if I, too, will have the balls one day to try this thing For now, I choose only to dream about it...

I was one of the two people who responded to this accident, it happened in March 1995 on Louise falls. I was one of a party of two climbing directly below this party; I had just completed my WFR training a month before. The leader of the party had just started out on the p3 pillar, but instead of taking the common line between the 2 pillars with some stemming, he came in from the bolted belay on the left and launched straight up the column. Half way up, with only 1 screw between himself and belayer, he started getting really shaky. Maurice and I were watching, because the leader was obviously in trouble. Then one of the leaders tools popped and he whipped, pulling the screw out of the ice. The leader hit the ledge below completely on his side, and kept going, tumbling down the route. He had lost one of his tools in the initial fall, it just ripped out of his hand, glove and all. He finally came to a stop as the belay held him, halfway down the 2nd pitch. In the meantime, the belayer casually announces, "ow. I just broke my leg." We helped the leader recover mentally, he was unhurt! Then maurice climbed up to the base of the third pitch and I rapidly followed, while a party below (doctor from Rocky Mountain House/Red Deer and a paramedic friend) helped leader dude down the route. At the belay, it rapidly became apparent what had happened. The belayer had clipped into the belay with a pearabiner only on his swami. As the load from the fall came against the belay, his torso was whipped from facing the rock to facing the load of the fall, as the pearabiner slid around his waist. However, standing on ice, his crampons and boots didnt swivel like his torso, and he got a nice greenstick tib/fib right at the top of his Invernos. We used athletic tape to splint up his leg, then lowered him down the route. He got helo-evaced out ot there, while his buddy the leader had to walk out under his own power and drive to the hospital. The moral is, always belay in such a manner so that if there is a fall directly against the belay, you are pulled toward the belay, not towards the fall. This could have been avoided with a quickdraw on the belay. This accident made it into Accidents in NA, 1996 I believe. Years later, I met the doctor and paramedics at Rampart, telling this story to some of their friends around the dinner table. It was only then that we were formally introduced Alex

as far as "mountain towns in the Puget Sound area" - hmmm Tacoma? It certainly has that frontier feel to it! North Bend, WA might be worth a look. Its growing really rapidly tho so dont know how long it will be considered a town. Bellingham is a good suggestion, especially if you DONT have to try and find a job there! Good climbing nearby, right on the sound so you can head down to Larabee State Park and put the kayak in the water, etc.

couple of places come to mind: Leadville, CO: I lived here a while, nice place. Rock climbing sucks, but the biking, whitewater, skiing, and hiking make up for it. Lake Placid, NY: very Banff-like flavor, good climbing too Leavenworth, WA: some kayaking, good climbing, terrible ambiance, tho, and hot in the summer Mazama, WA: if you can affoard it! The highway closes in the winter giving you 1) real mountian town feel 2) real climbing with no crowds, ever! Other runner-ups: Sand Point, ID. Cheap to live there! Good skiing. Southern Canadian Rockies nearby for ice climbing Pinedale WY? Its not Jackson, but its where all the real people live anyway.

regularly track daytime temperatures in Ephrata and Spokane, WA.

I like the product 2nd Ascent sells and still suggest you go there, or get your tools from the people selling here regularly on cc.com. There are really awesome deals to be had! If you want new, I bought a pair of Quarks for 130$ euro each from sportextreme.com this year and a pair of Prophets from Barrabes for 165$ american last year. I am all for supporting local gear stores, but not when it means paying twice as much for the same product (235$ american for a Quark at REI!!) Alex

sticky rubber grips better in cold

Went to Banff over Thanksgiving, here's whats up. General: not much snow except in the alpine, and warm weather everywhere. Rogers Pass: on the East side of the pass are some really nice looking lines to 5 that are probably not climbed often. Really compelling looking, but huge av terrain. Western Rockies: Kicking Horse has construction as you know, so you cant park or climb at the most easily accessible stuff. Pretty Nuts is there but very thin, Riverview is in but thin, everything else is not. In Field, nothing on Mt Dennis; Silk Tassel is in, Superbok out, Masseys out, some of the Yoho climbs look ok from the road. Temps in Field and Lake Louise in the early am about -5. In Louise, Louise Falls is in 5/5+ shape (it was climbed Sun am by two local guys), while Linda Ice Nine (Saturday, 4) is in good shape and holding up well to alot of traffic. Few parties (we were the only one on Sat of 5) are climbing the final crux pillar at steep and pumpy/wet 4. Parkway: Murchison. The Chinook is doing a real number on the Eastern Rockies. Banff: Rundle climbs...Trophy wall has all but come apart in the chinook. Professors in, most hardcores climbing it to Sacre Bleu. Sky Pilot looks in. Nothing else. KCountry: King Creek was reported in but wet a week ago by some people we met on Linda Ice Nine. Mt Kidd only has the first 10m approach pitch to Kidd Falls and Sinatra (Thurs, 2) and the first pitch on Sinatra is on the verge of melting out. Evan Thomas creek has been reported in, but it was like +6 when we were on Sinatra so I can't imagine Moonlight and Snowline survived the Chinook. Amadeus is dead. Ghost: Drove into the parking lot in the North Ghost and climbed the first few hundred meters of streambed on this House of Sky, past the first 3 WI2 steps (Friday). The streambed was dry above that (we think!!). We met two WA state climbers at the base of the route driving a Toyota truck...Layton? GBU is non-existant. Valley of the Birds approach pitch very thin. Burning Drowning was supposed to be in a few weeks ago but we didnt walk that far, it was really warm, maybe +5 during the day. Sorcerer is in and was climbed Fri by some locals driving an Outback. Hydro is in. Big Drip - that thing is huge!! Alex

mt dickerman and mnt loop highway are in Washington. get to Granite Falls, head east. Alex

I find it disturbing that pope is still thinking about this idea almost a year later. Check the date on the original post.

I climbed it Sat in great weather w/ partner. No one else in the upper valley, very nice place to be. Scoped out some very impressive looking rock climbs nearby, and will have to come back with the rock shoes and a rack next summer and send them! I wouldnt suggest you solo it the first time up it, but it is a nice solo once you've done it once or twice... Alex

yes, summit of Gothic, just a few weeks ago

I've got one up on you, chucKanut!

you were just lurking for that werentcha?

damn [ 11-20-2002, 08:39 PM: Message edited by: Alex ]

dont look now, but it was 16C in Calgary today, who knows what kinda season they are gonna get