by CAMERON McPHERSON SMITH
copyright 1996
GLACIERS AND CREVASSES: SMALL-PARTY CONCERNS
Glaciers : Basic Facts and Features
Alpinists, naturally, often find themselves on glaciers. Some alpine routes climb glaciers almost exclusively, while others require that you move on glaciers during the approach, or descent, or even somewhere in the midst of the climb. Whatever the case, you need to remember first and foremost that glaciers are large masses of moving ice. The bulk of the glacier moves slowly, even imperceptibly, but some portions of it will move very quickly indeed, and can be deadly. Even the apparently motionless features of a glacier, particularly the crevasses and seracs, are potentially deadly. Figure XX illustrates some glaciated mountain terrain and points out some of the features you will encounter. Study this carefully and apply the theory to photos of real glaciers; ask yourself "where would I go ? where would I NOT go ?". For more on glaciers, see Andy Selter's book Glacier Travel and Crevasse Rescue and The Mountaineer's Mountaineering : Freedom of the Hills. Don't go onto a glacier ignorant of what areas to avoid. Moving on Glaciers :
Equipment, Roping Up and Movement
You'll nearly always need to be roped-up for glacier travel. Even in summer, when the snow-bridges have melted and you think you can see all of the crevasses, there may be remnant snow-bridges that conceal deadly slots. Roping up for glacier travel is easy and there is no acceptable reason to avoid it to save time; you're dealing with your life here. On a glacier where the crevasses all seem to be apparent, with snow bridges mostly melted away, it's easy to just cruise along unroped, and keep telling yourselves that you can rope up if things get hairy. Bad idea. Rope up immediately. It's one thing to hang from a nice taut rope after punching through (or just slipping near the edge of a crevasse). It's quite another to find yourself wedged at the bottom of a crevasse because you were too impatient - or just plain stupid - to rope up. The first thing to do is to decide how many people will be on a single rope. In many cases the number is two, as technical alpine climbing teams are usually very small, compared to, say, mountaineering teams. The basic principle is that each climber should have, coiled on their chest, a length of rope long enough to reach the other climber should the other fall into a crevasse and need first aid and/or rescue. For example, with two climbers on a 165' (50m) rope, each climber should coil about 60 feet of rope around their chest. This leaves about 50 feet between the climbers. Now, if one climber falls in a crevasse, the other has just more than enough rope to set an anchor , run the rope forward and drop it to the other climber, or help haul them out. The principle is illustrated in Fig. XX. On a 330' (100m) rope, the two climbers should each coil about 120' of rope, leaving about 90' between them. Rigging for glacier travel is illustrated in Figure XX. Here, I am most interested in the standard alpine situation where two people are traveling on a single rope. To rope up for two-person glacier travel you first tie into the end of the rope as for climbing. Now measure out the appropriate length of rope (see above) and coil this not too tightly and not too loosely around your chest. It's handy to remember how many arm-lengths of rope you take to get the right amount coiled so that you don't have to think about it every time you rope up for a glacier. You want to be able to get the coil off quickly if needed (so do it after you put on your pack), but you don't want the loops to be clumsy and tangling in gear. Now, draw a bight of rope up through the coil, tie an overhand knot with the bight and clip this into your central harness carabiener. See Figure XX for clarity. Now run the rope that leads to your partner up your chest and through a carabiener clipped to a shoulder-strap of your backpack. This may prevent you from toppling over backwards if you fall into a crevasse, ending up hanging on the rope. Each climber should carry three pulleys, for the crevasse rescue techniques described below. You don't necessarily have to carry heavy-duty rock-climbing pulleys, though; for the loads of crevasse rescue, the compact and almost weightless plastic tubular pulleys, which are just rings wide enough to accept a rope, slid onto an oval carabiener (not a 'd' carabiener, though), are adequate unless you're climbing with King Kong. Some pulleys are illustrated in Fig. XX. Finally, take three prussiks or kreutzklem knots, or ascending devices if you're carrying them, and attach two them to the rope in front of you, and clip them to your harness with slings as shown in Figure XX. This is done so that if you do fall in a crevasse and can't climb out, you don't have to bother with finding your ascenders and getting them on the rope, perhaps dropping them in the process. This is also important for setting up a rescue pulley-system (see below), so don't neglect to do it. The third ascender or knot should be clipped somewhere so that it is readily at hand. Some climbers like to put a knot a few feet up the rope leading to the other climber as shown in Figure XX. This is so that if the other climber falls in, one can set an anchor and clip straight into the rope. At first this seems a reasonable precaution and you may be tempted to do it. Don't. If you end up having to do a rescue with a pulley system, this will make things extremely difficult. This will become clear in the section below describing the set-up of rescue-pulley systems. Finally, clip your rescue anchors (screws or otherwise - see below) to your harness or pack such that you can get to them with one hand; in a rescue situation this will be critical. A two-person team with limited anchors for rescue would do well to have the second climber carrying these anchors. Figure XX shows a fully-rigged Glacial Pedestrian ready to go for a two-person stroll. It's a good idea to memorize the glacier roping system as it does take some time to rig and you may be tempted to avoid it because of this. At home, set up the system with precisely the right slings and prussiks required, so that it all fits well. Now mark the right slings with a dot of color, or whatever, so that on the glacier you don't have to figure out all the lengths again. Once you're roped and ready to start off, let the leader head out until the rope is reasonably taut between you. This is critical. If there's much slack between the two of you and one climber falls in, the fall will generate a shock-load to the other climber, probably throwing them off balance and perhaps dragging them into the crevasse if they can't self-arrest or stop themselves some other way. A hideous way to go. On the other hand, if the rope is taut and one person falls in, the shock to the other climber may be minimal. You may not even be thrown off balance, especially if you're keeping a close eye on the leader as they cross suspect areas (sometimes you'll belay them across, see below). Also, a lack of slack will prevent the hapless faller from going in too far, whereas a length of slack between the two of you will allow them to fall much further down the crevasse. Clearly, you must keep the slack to a minimum. These principles are illustrated in Figure XX. Luckily, keeping the rope taut is pretty straight-forward in most terrain, but requires close attention. The leader and second must carefully adjust their speeds. If the leader wants to go around an obstacle such as a crevasse, and the second just keeps plodding on straight ahead, slack will build up. The leader may go a bit faster to compensate, but it's safer for the second to just keep an eye on the leader and slow down to wait for the rope to go taut before following. Of course, the leader must keep an eye on the second as well, adjusting their speed accordingly. Basically, keep your eyes open and keep the rope taut. Next to avoiding crevasses altogether (which is difficult on a glacier !) this is definitely your best defense against taking bad crevasse falls. Sometimes it will be necessary to belay the leader as they cross suspect features. Personally, I like to belay (and be belayed !) even on the most sturdy-looking bridges, even if it's only with a boot-axe belay (see the section on Belaying in Snow). I just assume that all crevasse bridges are suspect and act accordingly. On the strongest-looking bridges (these often are very sturdy, sometimes even contacting ledges below), as mentioned, a simple belay may suffice. On anything less sturdy, place at least one anchor. Many times on a glacier you can get a picket or dead-man into the surface, and this may be enough, especially if you keep a taut belay. However, if the bridge is very wide, and the fall potentially long, you should consider digging beneath the snow to find suitable ice for a couple of screws. Place these anchors as described in the section on Ice : Anchors, and make sure they are secure and tilted a bit further back from the perpendicular (about 20 degrees or so) than usual. You may want to belay directly through the anchor slings; if the leader goes down you may as well be prepared to instantly anchor them off and get straight into assessing the situation. Once the anchors are set the leader can head out, so long as their ascender devices are on the rope, ready to go. KEEP A SUPER-CLOSE EYE ON THE BELAY - allow just enough slack so that the leader can keep moving. The leader can cross any way their courage and intelligence deem appropriate. You may walk, jump, crawl, slither or swim across. On the most suspect bridges (having selected the best of the suspect bridges), keep your weight as evenly distributed as possible, as if crossing a lake covered with a skin of ice. Once on the other side, try to swallow your heart, set up a belay, and bring across your partner. Mission completed. Only twenty more to go ! Figure XX illustrates the main points to keep in mind when belaying across snow-bridges. Finally, you have to decide whether you want the heavier climber to lead or to take up the rear and belay. If they're appreciably heavier, bringing up the rear is a good job for them as this will help them with holding a fall. On the other hand, you may want to have the gorilla lead, with some assurance that, if they've made it across a bridge, it'll probably hold your weight (assuming the bridge hasn't been damaged by their crossing). Best to trade off jobs as the situation demands. Keeping your weight distributed across the greatest surface area is most effectively done with skis or snow-shoes. Though many times these are used in alpine approaches, their use is way beyond what I can discuss here. If you're heading out for a major adventure, consider these excellent aids to snow-travel, and learn to use them effectively. If you've never even used skis, don't be intimidated. It's a lot easier to learn to ski than you may think. If you're descending an appreciable slope, a leader-fall into a crevasse can be very serious as it may drag the second climber right in, totally unable to fight the drag even with a sturdy self-arrest. In this situation, consider belaying on the steep sections. Things are a bit better if you're ascending a slope and the leader goes in, as the increased friction of the rope on the lip of the glacier may reduce the potential shock. On the way down a slope, if the second falls in, the shock shouldn't be too bad. If the second falls in, though, as the leader is ascending, the situation can be critical for the reason described above. Belay as the situation and common sense dictate. On 'slippery' glaciers where there is little or no snow to self-arrest in when trying to catch a fall, be particularly safe. Self-arrest on bare ice, as mentioned in the section on Snow : Descending, can be extremely difficult, if not impossible. Despite all the precautions, you or your partner will probably end up down a crevasse, some day, hanging on the rope or standing on a ledge of ice or snow. In this case, you'll need to get out, and quickly. Crevasses : Two-Person Rescue Technique
A lone rescuer facing the task of getting their partner out of a crevasse is facing some major problems, and again I must state that it is extremely important to stay out of the crevasses in the first place. The lone rescuer will soon find that it's a ridiculous proposal to haul their partner out of a crevasse with bare hands. They will need to increase their mechanical efficiency with a pulley system. This is described below, and must be memorized, not just read once over. You need to be able to set this up quickly and in poor conditions. It's a good idea to practice it a few times on a trip to a glacier some day. You may want to do a climb, but you'll be thankful you met the real problems in a practice session when you eventually find yourself out there, your partner unconscious on the rope and you very, very alone. If You're the One Down the Crevasse
So, there you are, down a crevasse. The first thing to do is to try to contact your partner and establish the situation. Shout. If they reply, tell them what your situation is. Perhaps they just need to lower you a few feet to a ledge (test it - it might collapse !) from which you may be able to walk laterally out of the crevasse, or at least take your weight off the rope as they anchor it. Perhaps you can just get your ice tools and start climbing up the wall of the crevasse. This is the best-case scenario. If you feel OK and can easily climb out, just start up, then stop after a few feet, if possible, when you can take the strain off the rope. The sooner you get your weight off the rope, the sooner you can relieve your partner, who may be having big problems. Once you do get your weight off the rope, wait a bit and try to contact your partner again. If this takes some time, consider placing a screw or your tools in the crevasse wall and hanging for a bit. If you can, wait until your partner tells you they have an anchor in, and that you're on belay, before you continue up. If you fall again, perhaps while they're setting up some anchors, you compound the problem. If you hear nothing after a while, get going and climb out. As you ascend the ice, take particular care not to chop the rope with one of your tools. If your partner is not able to belay you up, tie in every 20' or so as the rope goes slack beneath you. If you're hanging free on the rope but there is no ledge close by, and the crevasse walls are unclimbable, for whatever reason, determine whether you can get out by ascending the line you're hanging on. Establish contact with your partner. If they tell you they've got some anchors in, get going. You should already have your ascenders on the rope; get onto them and start up. Follow the procedures described in the section on Techniques for Ascending Fixed Ropes. If you can't establish contact with your partner you have to decide whether to get started immediately, as you may do if they had you on belay (which should now be locked). On the other hand, if you were not on belay, your partner is probably lying flat on the glacier, dug in the self-arrest position, trying desperately to get some anchors in. You may be afraid that if you start up right away, your inevitable bouncing may load the rope in jerks, making your partner's task even harder. This is unlikely, however, unless you're really going to go wild. The rope running over the lip of the crevasse should minimize the shocks. Only if the lip it is bare ice is it likely that they'll feel anything except a terrible steady, pull. Now, if your partner has managed to get in an anchor rather quickly, you may be able to start off right away in complete safety. The importance of communication becomes clear here, but, alas, it is not always possible. Use your head and consider the circumstances on the Upper World. Get out of the crevasse as soon as you can. It will be cold down there, perhaps wet as well, and you don't need ice water dripping down your neck to compound your problems. Moving along the scale of seriousness, you may find that you've been injured in the fall and can't get yourself out of the crevasse under your own power. Again, try to contact your partner as soon as possible, and let them know you need to be hauled out. If you can get in touch with them, try to help them as much as possible; you may be in a nasty spot, but your partner's not exactly having a tea-party up there. Let them know if the lip of the crevasse above is unstable, so that they're extra-careful if they approach the edge. Tell them if there's a bulge somewhere above that you might snag on while you're being hauled up. Tell them as much about your situation as you can. Whether you can get in touch with them or not, your next task is to assess your injuries and, if critical, treat them as best you can. To say this may be difficult is an understatement, but you should at least make yourself aware of your condition. Next, if you're not already warmly dressed, get on a hat, gloves and a jacket or sweater. You may be awaiting rescue for a long time (or it may just seem like a long time, but the distinction is probably not your greatest concern), and you should protect yourself against hypothermia and frozen hands. Getting dressed may be difficult, but you must try. Shrug off your backpack and let it hang on the rope at your harness (it should already be clipped in if you're properly rigged). Get out the clothes you need, and perhaps have a bite to eat (nothing too elaborate, though!). You can then clip the pack to a more comfortable position, such as under your harness, as described in the section on Techniques for Ascending Fixed Ropes. Now, warmed, or at least insulated, and perhaps fed, make yourself as comfortable as possible. Get a chest-harness rigged up, pronto. This will save you precious energy and free your hands. Try to relax and try to help your partner in any way you can. Once you're being hauled up, and you reach the lip of the crevasse, try to help with heaving yourself over the top. Chop away ice or snow if you can, clearing a path to be dragged up so as to reduce resistance. This is often the most strenuous part of the rescue and can put a great strain on the anchors; you are wedged up against the lip and your partner has to haul harder and harder to get you over the edge. Finally, if you're unconscious at the end of a crevasse fall, things are going to be very serious. Here we must switch scenes to the climber up on the surface. If You're the One On the Surface
So, your partner is down a crevasse. If you were alert, with a good, taut rope, they may not be too far down, and they may be able to haul themselves right up. You have reason to rejoice - this is the best-case scenario. If the fall was more serious, and you had to self-arrest, or are standing, but being dragged down to the glacier surface by the strain (which is a pretty awful feeling), the first thing to do is to get in some anchors and get that strain off of your harness. If you're in the self-arrest position, keep one hand on the axe and, using the other hand, try to get in some anchors. This is difficult and precarious, but you have no choice. In good, deep snow your best bet may be pickets, or dead-men, though deadmen are more difficult to place with just one hand. It's a good idea to have anchors ready to unclip from your harness with one hand before you set off across a glacier. The best thing you can do in bad snow is hack away at the surface snow and sink a reasonable number of good ice-screws (two at least, and preferably three or four). Do this as described in the section on Ice : Anchors, with the exception that the angle of the screws should be greater than usual; tilt them about 35-40 degrees from perpendicular, away from the load. These anchors are going to be under a lot of strain if you have to start hauling. It is critical that you equalize the anchors with sling or rope, somehow. Again, have these ready to unclip with one hand. See Fig. XX for an illustration showing a climber setting anchors one-handed in a rescue situation. Now that your anchors are set, you can tie off the rope to them. Clip the anchor sling to the ascenders (knot or mechanical) you already had rigged to the rope by unclipping them from your harness and into the anchor sling. They should lock and take the strain from your harness, and you can slowly ease off of your self-arrest and let the rope take the strain. See Figure XX. Now that the rope is tied off and you're free of the strain, get in touch with your partner. If it's possible to shout to them without moving, stay put. If they can climb up without help, just wait for them to unweight the rope and then belay them up with the rope they fell in on, once a bit of slack is available. If they can't get out on their own power, you'll have to go and get them. Untie and then uncoil the rope around your chest, fix a new ascender knot to it as a safety as shown in Figure XX, and approach the lip of the crevasse. Be careful; you don't want to fall in as well, and you'd be surprised how often this happens during rescues. Have a look down there. Scope the situation. How does your partner look ? Try to contact them again. If there's no response, place an ice axe or other pad on the edge of the crevasse, under the rope from which your partner is hanging. This should stop the rope from digging too deeply into the lip of the crevasse, which can be a major problem. Now, go back to the anchors and place one or two more equalized anchors as back-ups; you're going to be loading this rig for a long time. Now you have to set up a pulley rescue system. The previous steps are illustrated in Fig. XX. If your partner appears to be seriously injured, or unconscious, you've got a real job on your hands. You must rappel off of the anchors you've just set, get down to your partner and put a hat on them to keep them warm, remove their pack, and fix a chest-harness so they don't hang upside down. See Figure XX. This may seem complicated but it is not as bad as it seems. The main thing will be to reinforce your anchors, as now two of you will be hanging on them and you'll be coming back up the rope in a few minutes. When rapping down to your partner, use a saftey knot or ascender to hang from as you set up your partner with the appropriate slings; if you come off the rap-rope the situation will enter the realm disaster. Set-Up and Use of a Rescue System for a Single Rescuer
Being alone, you're going to need a very efficient pulley system to get your partner out of the crevasse. The normal 'Z' pulley system is ok when there are more than one rescuer, but in this book I'm more concerned with the situation in which a lone rescuer has to retrieve a partner. The 'Z' system is illustrated in Fig. XX, but don't be tempted to use it because it looks easier and less gear-consuming than the more efficient single-rescuer system. It will rarely work and you will have wasted priceless time and energy. The 'ZxC' system is the best system for single-rescuer use. Practice the set-up at home until you can do it by memory, then try it out on a practice session on a glacier. This is one of the skills you really don't want to try to remember when it comes time to use one and your partner is hurt, perhaps badly. Look at the pictures, read the text, then set it up yourself. Memorize this system and make sure your partner memorizes it as well. OK, you're committed to a major episode here; recall your training sessions and get to it. Follow the text with Figure XX. First, clip a carabiener through the anchor sling and clip your pulley to this carabiener. Now take one of your ascender devices or knots and go a few feet down the rope. Attach the ascender or knot to the loaded rope (you haven't done anything with the slack rope yet), and to this clip a carabiener with a pulley. Now feed the slack rope it through the pulley you've just attached to the ascender knot. Go back up to the main anchors. Feed the bight of rope formed just above the ascender knot, which is holding the strain, and the slack rope, through a belay device directly under the anchor pulley. Figure XX illustrates this clearly. Now take the slack rope, which should be fed through the non-anchor pulley on the load rope, and tie it off onto the anchors, pulling tight so that it starts to lock the non-anchor ascender or knot on the loaded rope. Now take more of the slack rope and feed it through another pulley attached to another ascender knot, this one attached to the rope you just tightened. You are ready to haul. The whole set-up and sequence is illustrated in Fig. XX. Now you can begin hauling. Grab the slack line and pull. You may find it easier to knot it, clip it to your harness and, using your crampons for purchase, pull like an ox. Whatever the situation, you pull away from the crevasse and the pulleys go into action, hauling your partner up slowly but surely. After each haul the ascenders or knots should grip the rope and keep your partner from slipping back down. If they don't, and they are knots, you'll have to re-tie them so that they are tighter. This is an excellent reason to carry a pair of mechanical ascenders on glacial climbs. Once your partner nears the lip you may have to chop away some ice or snow there, if they're not capable of doing it, so that they can come up over the edge with a minimum of resistance. Take care not to knock your padding into the crevasse when you do this (you can just anchor it with an ice axe or picket or something; see Fig. XX). Also be careful with your axe and crampons around that taut rope; it'll part very easily under such strain. Finally, if this is an extended operation and it's hot or sunny, cover the anchors with snow to keep them from melting the snow or ice and pulling out before the job is completed. The 'ZxC' system requires three pulleys and three ascender knots or devices, but it is too important to neglect when the standard alpine team of two are traveling on a glacier. It is obviously a major operation, and the best thing - once again - is to stay out of crevasses in the first place. Of course this is not always possible, and I cannot stress enough how important it is to memorize this system and carry the required gear; to find out just how critical it is, go out to a glacier some day and try hauling your partner out of a crevasse with a standard 'Z' system. You'll soon be carrying three pulley-rings and three ascender knots on all your two-person glacial excursion. A final note; if you find the prussik to be unsatisfactory during your glacier training sessions, consider using the autoblock, illustrated in Figure XX, at the main pulley/anchor station, as shown in Figure XX. The autoblock tends to be easier to use, depending on the snow conditions and temperature.
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