Loved by charities but often hated by climbers, abseiling can be much more dangerous than climbing. When else do you stick all your eggs in one basket and then bounce up and down above a precipice? Steve Long from Plas y Brenin takes a horrified look at the mistakes he's got away with, but wouldn't like to try again.
1. Dodgy anchors
These have a habit of disintegrating when you pull hard enough on them. Some are quite cunning; they look tolerable at first glance and only reveal their weaknesses to the more discerning or experienced suitor. The trick is getting enough experience in before they catch you out. Take a really good look. Is surrounding rock good quality or is it shattered? Are there any cracks nearby? Give the anchor a really good tug in various directions (but make sure you’re securely positioned or clipped to something else in case it disintegrates). Never get blasé about anchors you’ve used before; erosion is constantly at work, and there have been many cases of blocks that worked for years but then one day decided to shift. Maybe get your partner to watch the anchor while you push and pull; sometimes it’s easier to see movement from further away. Don’t assume that in-situ (“already in place”) anchors are sound just because they have been used before. Look for signs of corrosion, fractures, and movement. Check the slings for signs of abrasion; pulling rope through a sling after abseiling generates a lot of friction and heat, sometimes enough to burn right through the sling after just one abseil. The golden rule is:
If you don’t trust it, change something!
Single anchors should be regarded as the exception that proves the rule. Try to link at least one other anchor, and arrange the connection so that the anchors are equally loaded - and loaded in the direction that they will get pulled (often slightly outwards). That way if one anchor were to fail for some reason, the remaining parts of the belay won’t get shock loaded. All too often anchors are very poorly equalised, and a few minutes will have to be spent adjusting them to spread the load properly; this would take seconds if done properly right from the start.
Don’t take risks to save money. Carry some cord and a karabiner you don’t mind sacrificing, or just bite the bullet and throw some brand new gear at the problem. How much is your life worth? This holds true even for unplanned multiple abseil retreats, but here there may be an extra problem; you might not actually have enough gear to really “lace” the belays. In these situations a compromise may be necessary. Anchors should still be good, but you might need the back-up gear for abseils lower down. Set up with fail-safe secondary anchors but leave these slightly slack so that the main anchor is taking the entire load. Send the heaviest person down first, and watch the anchor very carefully. If satisfied, strip the back-ups and follow on down gingerly, minimising bounce. I once descended the whole of the Dru in this way, arriving back at the ground with nothing left of my rack, but in this case only my wallet was injured!
Remember the direction of pull. The classic mistake here is pulling outwards on a blunt spike, especially as you get established setting off from the ledge. Be paranoid. Load the anchor with the direction of pull that it wants to take. If necessary belly flop off of the ledge to keep the loading as close to vertical as possible. It may not look glamorous but neither is plummeting.
2. Letting go of the ropes
Abseiling only works if you can keep a good grip of the ropes! Avoid “classic” (i.e. no abseil device, just body friction) abseils on steep ground. Jim Perrin tried one of these many years ago on the Red Wall and only just got away with it, but he still carries the scars.
Don’t abseil from a device still clipped to your gear loop. This sounds obvious, but you'd be shocked at how often people do this. Even Instructors aren't immune - I once had a blazing row with my girl friend then launched out over an overhang above a 50m void. Once committed I found that I was hanging from a very tatty old gear loop. Prayers seemed to help on that particular occasion, but a better tip is to carry the abseil device near the back of your harness so that it can't be used without unclipping it from the gear loop.
Back up the abseil device. Whatever abseil device you use will not behave properly if you let go for some reason. Believe me, I’ve tried that one too. Fix some sort of auto bloc system to the rope, which clutches the rope if you let go. The classic method is to fix a French prusik to the rope below the abseil device, and attach it to a leg loop. The prussik is held in the controlling hand and grips the rope if the abseiler lets go.
An improved method is to rig the abseil device so that it is attached by about 30cms of sling to the harness abseil loop. This prevents the gear loop problem mentioned above, but also prevents the prussik riding up and releasing by touching the abseil device in the event of unconsciousness. I use a long sling connected to my harness abseil point with a lark’s foot hitch and then knotted at about 30cm. A karabiner on the other end of the sling can be used to attach myself to the next anchor when I arrive, and is clipped to the harness out of harms way as I abseil.
Bear in mind that different abseil devices behave differently. “Slick” devices such as the ATC give very little friction when abseiling on a 9mm rope, and a method of providing additional friction is almost obligatory in such circumstances. And remember - all devices provide less friction when used with brand new ropes.
Passing a knot. Do you really have to? It’s much better to get a longer rope if you can. I keep a 90m static rope stuffed in a caver’s rope bag for bigger approach abseils. I hang the bag off my harness and just pull out a metre or two of rope at a time; thus protecting the rope if I knock off any blocks on the way down. But if you do find yourself having to pass a knot you'll need to use skills that are best practiced a few inches above the ground rather than trying them out for the first time above a yawning void.
Join the ropes with a knot that includes a fixed loop, allowing you to clip into the loop as a back up while you change over. Place the back-up prussik above the belay device, connected to the harness by a sling. The length is fairly critical because if the sling is too long, it’s the devil’s job to unfasten the prussik (because you can’t reach it) once you’ve transferred from one rope to the next. The routine is as follows; abseil to within half a metre of the joining knot, lock off the prussic and transfer your device to the other rope. As I mentioned, clipping into a loop incorporated into the joining knot is good practice. Once transferred, lock off the abseil device and release the prussic. This may be quite difficult; if it’s stubborn, use a second prussic to make a foot-loop. Step up using this to un-weight the jammed prussic and unclip/release it. The foot-loop prussic can then be attached to your harness leg loop as the new auto bloc.
If your harness has a central attachment loop (often called a belay loop), use it. It spreads the load between the leg loops and waist belt much more effectively than a karabiner. There are still people who believe that it is better practice to clip the karabiner itself into the two parts of the harness, but in almost all cases this can put a potentially dangerous 3 loading on the karabiner. Furthermore, used in conjunction with a Figure of Eight device this has resulted in the locking gate getting broken and causing serious injuries.
3. Abseiling off the end of the rope
Not a good idea; it has been tried. Unless you can see that the rope touches the ground, tie a stopper knot in the bottom end of the rope. It doesn’t matter what knot you use as long as long as it doesn’t fall apart and is big enough not to pass through your abseil device. For good measure leave about half a metre of rope beyond the knot so that it can’t creep off the end of the rope if weighted.
If you are abseiling on doubled ropes, put a separate knot on the end of each –that way they are less likely to snag. And always undo the knots before you try to retrieve them.
4. The anchor sling melts
If ropes are threaded through a sling and allowed to slide under load this can very quickly melt right through the sling, with very serious consequences. A typical scenario is abseiling on ropes of very different thickness. Under load one rope stretches much more than the other, resulting in creepage. Use a karabiner to link the ropes to the anchor if you see this as a potential problem. A less sure fix is to place the knot joining the ropes together butted right up against the sling, with the thinner rope passing through the anchor sling, this should lessen the creep.
5. You’ve reached the next anchor but the ropes won’t pull down
This happens depressingly often, either because there’s too much friction, or the knot joining the ropes has jammed. Prevention is always better than cure. Extend the belay with tape or cord if it looks like there will be a lot of friction - it’s a pain but much better than prussiking all the way back up the pitch. Leaving a karabiner behind will drastically reduce friction - use a screwgate or fix a snapgate shut with sticky tape. Try to use a slim profile knot. The favourite is a simple overhand knot with long rope tails to prevent the knot creeping undone under load. However, avoid tails of much longer than half a metre or you risk abseiling off the wrong end of the rope by mistake! Get the first abseiler to test that the ropes pull freely. Just a few inches, otherwise you risk heat damage if the rope is threaded through slings.
6. The ropes pull through but jam on something part way down
This is a real pain but don’t try to prussik up on of the ropes; if the rope suddenly releases you will fall. Instead it’s safer to climb back up to the obstruction. You may have pulled enough rope through to be able to use the end of the rope as a safety line and place runners if necessary. If you can’t climb the rock then you really are in trouble! You may even have to cut the jammed rope. Try to prevent this problem by observation. Spikes, trees, brambles etc. like to grab hold of falling rope ends, so choose an anchor above a clear run if you have a choice. Abseil to one side of the potential snag and retrieve the ropes by carefully pulling to the side. Sometimes you can use a feature such as a groove to keep the ropes away from obstruction as they fall. A related problem is failing to notice knots in the rope before you pull the other end. The knot hits the anchor sling and jams. This is best avoided by observation, particularly by checking the end of the rope before it disappears out of reach.
7. The sea swallows the end of your rope
If you leave the end of your rope dangling in the sea, it will probably get sucked down and wrapped around something under water. Avoid this by keeping hold of the rope end when abseiling above the sea. Coil the end of the rope out of harm’s way after you abseil down to approach tidal routes.
8. You abseil down the wrong line
Sometimes you have no choice but to prussik back up the abseil rope. Make sure you’ve got some gear to do this, and learn to prussik somewhere less serious.
9. Climbers get angry because you’ve abseiled down their line
This boils down to consideration for others. Try to avoid abseiling down the lines of climbs in the first place; several fine climbs have been spoiled or even ruined by careless feet or sheer volume of unnecessary traffic. There are plenty of less environmentally sensitive places to practice rope skills. For a forced retreat, have a good look down the pitch before launching off and yell out “rope below!” or something similar before throwing the end. If you have to pass climbers on the way down, carry the ends of the rope down with you and take care not to knock the leader off on your descent.
10. The abseil tree has died
They have a habit of doing that. Ways to minimise the damage include: Walking down if possible, protecting the tree by using tape, and taking care not to damage the roots or erode the earth. Arrange alternative anchors if available. Bolts might be a necessary alternative but should only be placed if a consensus is reached by discussion at the local BMC area meeting.