Why do mountain climbers tether to each other?

Factual Questions
1

I just saw Vertical Limit on video. I did an SDMB search and found a few threads on the movie, but not this question. In the movie, two or more climbers are tethered together…so, when one falls, they all fall!

2

The hope is that if one falls, the rest have a good foothold to keep everyone together and safe. The best thing to do would be to hammer stakes into the ground at regular intervals to be anchored to, but that would be too restrictive and time consuming (plus they would have to bring around a LOT of heavy gear with them). When everyone is on the move the only thing they can tie down to is each other.

3

Or if the others are properly attached the one that falls is saved. IANAMC but I think the theory is that there should be at least one or more climbers securely attached just in case.

4
      • I haven’t seen the movie, and I haven’t ever used anchors because where I am the rock is to soft, and I haven’t ever been to Everest because I am poor, but the way face climbing in pairs works is this:
        -The climbers typically use anchors of some type that hook onto the rock, in case they fall. The anchors can be pitons that are a type of bolt which are hammered into the rock or screwed into ice, but usually they use some type of removable device that wedges into a crack easily somehow but is difficult to pull directly out. The three main types are wedges (some frighteningly small), hexes and cams.
  • As they climb, the first person climbs and places the anchors into cracks as he/she ascends, and the back person takes the anchors out as they climb to them. They bring along another cord so that when the lower person has all the anchors the upper person drops one end of the cord down, and hauls all the anchors back up and begins again. Or the upper person can just stop and let the lower person get all the way up to them at some convenient point, but they try to have at least a couple anchors in at all times. This way if either falls, there’s at least a couple anchors in the rock to (they hope) keep them from falling. Sometimes tho it don’t work that way and yes, one person falls and everybody on the rope goes down.
  • Regular mountain climbing works much the same way: there are deep cracks present under the top layers of snow that climbers fall into, and it is hoped the second, third and fourth guys can keep from being dragged in with the first guy. A couple years back a relatively famous climber (I can’t recall who 'twas) was in an area generally considered safe on Everest and fell into a crack untethered. The others decended 200 feet on equipment they had but could not see him or the bottom of the crack, and he was lost. Crevasses regularly open up and close in glaciers as they shift, and can’t be predicted, and you can’t often see them because the top layer of snow doesn’t always collapse and fall into them. - MC
5

IAAMC, and the reasons for doing so vary.

It’s a safety precaution, but every climb, every route, every pitch must be weighed as to which is more dangerous–clipping together or going it alone. Some high-altitude climbs pose such extreme objective danger and the climbers themselves are so enervated that roping together is not an attractive option. Were one climber to peel off the side, he could easily pull the other(s) with him, with unenviable results. Better each climber do his best and take his chances as no one at that altitude has the strength or speed to effectively arrest a falling member. Certainly not two or more on steep climbs.

Clipping together is important on glaciated, heavily crevassed climbs. If on Denali or Rainier in early summer, for instance, many of the (deep) crevasses are hidden by snow and falls are not uncommon.

Up K2’s standard route, same story–it’s a judgment call. K2 is perilously steep on all sides and a fall on some exposures (at say 26,000-27,000 feet) could find you cartwheeling all the way down to base camp. This very thing almost happened in the mid-50s when the first K2 American team was trying to take down an ailing member and someone slipped. In a flash, six men were hurtling down K2 and would have fallen to their deaths if not for the miraculous belay of Pete Shoening. Ditto with Ed Viesturs and the late Scott Fischer in the early 90s.

On Everest’s standard south/southeast route, climbers always clip in when ascending the massive Lhotse Face. Were you to slip unroped, you would rocket down the face and quickly become one with Everest. Fixed ropes are also used above the South Col, especially from the Balcony on up to the South Summit and on to the Hillary Step–this latter section (a knife-edge route with perilous drops on either side) being the highest objective danger of the climb. Were you to slip unroped between the South Summit and the Step, you probably couldn’t self-arrest fast enough before falling 8,000 - 12,000 feet down either face.

The same is true of rock and big wall climbers. Clipping into one rope is usually a standard safety procedure.

6

So the sensible ones can’t go home…
(Sorry)