A look at the essential skill of abseiling. What do you need to know to get down in one piece?
Abseiling is an essential skill. And, despite it sometimes being presented as a glamorous activity, abseiling has caused more fatalities than any other mountaineering activity.
When to abseil
Abseiling involves descending rope(s) using a friction device (e.g. belay device) attached to your harness. It’s used to tackle terrain that would be too dangerous or time-consuming to descend on foot. For example; escaping a route beyond your ability, descending from a pinnacle, or approaching the base of a sea cliff.
If you have never abseiled before start at ground level down a shallow slope, before doing it for real. Then move on to a small cliff (not down a popular route on a sunny day!) Look over the edge to check no one is below, and with one rope end attached, stack the rest into a neat pile, then holding the last few metres in coils throw them out and down. Be careful, shout ‘Rope below!’ loudly to warn anyone, then check that the ropes reach the ground.
Attach the belay device to the central loop of your harness with the rope running through it, just as when belaying. With both hands locking off the control rope adopt the same body position as when lowered off a route: lean back and legs apart. In this position you will gracefully abseil down the cliff as you let the rope slide through your hands. Or you may judder nervously if it’s your first time.
The take-off is often the hardest part of abseiling as you are leaving the horizontal cliff top for the vertical cliff face. If you find it awkward consider sitting on the edge and slowly sliding off. This lowers your centre of gravity making you more stable.
Making it safer
When abseiling you can easily slip and let go of the rope with drastic consequences, so it’s a very good idea to use an autobloc as a back up to hold the control rope if you let go.
The most common autobloc is a French prusik, made using a prusik loop. It’s so effective and simple to tie that there’s no need to travel without it.
To make a French prusik wrap the prusik loop around the control rope four or five times. Clip both ends with a karabiner and attach that to the leg loop of your dominant hand. If you have too many turns it can be very hard to release it, so get to know how many you need. When held in your hand the knot is loose allowing the rope to slide freely, but if released it grips the rope and prevents further progress.
Remember that the prusik is not fail-safe, it could rub against something and release, so always try to keep hold of the control rope.