The Basics of Abseiling

by Don Russell,

A figure of eight descender, single & double figure of eight knots and a steel HMS screwgate.

A figure of eight descender, single & double figure of eight knots and a steel HMS screwgate.

Learning to abseil can be a little scary; knowing a little more about how it all works can often make it easier.

Being able to abseil has a number of advantages such as descending waterfalls in large gullies safely, being able to get down quickly from a climb if caught in bad weather or simply to repair something on the side of a tall building are only three examples. The military use abseiling for window entries when assaulting from above, descending from helicopters (although ‘fast roping’ is more often used) or descending cliffs either forwards or backwards.

The Equipment is minimal and simple to use, they are listed below one item at a time. Of course, there are many different types of descender on the market to choose from; here we are looking at the basic equipment and method although you can abseil with only a rope if you have nothing else. Once you can abseil you will be able to adapt easily in order to use any combination of equipment to suit your application. It is the mental aspect that can be the most difficult to come to terms with and this generally is only when going over the edge initially.

The Anchor

Securing the rope may involve ‘stropping’ a substantial tree or rock, using existing ‘bolts’ or placing mechanical protection into cracks. Look at how experienced climbers place their protection into the cracks along with the direction and shape of the cracks in relation to the position of the load.

The Knot

The only knot that you will need when abseiling is the figure-of-eight knot in one of its many forms; if clipping into a single karabiner a single figure-of-eight knot finished with two half-hitches, the multiple coil of a scaffold knot or the tidier double overhand stopper knot is all that is required. If the anchorage points are fragile you may consider spreading the load over two or even three anchors; the double or triple figure-of-eight knot can be used,
again finished in one of the methods described above.

The Harness

Climbing harnesses come in all shapes and sizes and some time should be allowed to shop around in order to find one that fits well and is comfortable; when buying the harness it is important to ‘hang’ from it to ensure that it does not cut into you anywhere. Don’t worry; the retailer will have the facility in store to do this, in fact a good retailer will insist upon it. If you are going to be abseiling forwards you will need to go for a full harness to prevent sliding out of it during descent. You can adapt a normal harness with the use of a climbing sling for this purpose but get a climber to show you how it’s done properly.

The Rope

The type of rope will almost certainly be of kernmantle construction, ‘kern’ being core and ‘mantle’ being the braided protective outer as opposed  to hawser laid (twisted) ropes that can have a life of their own when abseiling due to their twist. Kernmantle ropes come in two main types, dynamic and static; the dynamic being used for climbing as it stretches to break any fall and static that has only a minimal extension and is used for abseiling not climbing. Both types may be used for abseiling but if you are using a rope specifically for abseiling a static rope is preferable such as ‘Black Marlow’. A diameter of around 7/16” (11mm) is generally accepted as the best with most descenders.

The Descender

There are many types of descender on the market but the figure-of-eight remains a very basic, no frills, no moving parts, light, bullet-proof, piece of equipment that’s present in most people’s kit; this being the case, a basic figure-of-eight is probably the best one to start with.

The Karabiner

To attach the figure-of-eight descender to the harness a karabiner is required. It is extremely important to use a ‘screwgate karabiner’ to ensure that it cannot open due to any outside influence acting upon the gate; if the gate should open it is unlikely that the descender or harness would detach but it would reduce the SWL (safe working load) of the karabiner substantially. As an ‘old timer’ I always use a steel screwgate karabiner for this purpose (much to the amusement of the younger lads) but there are lighter alternatives, all completely safe. I also favour the H.M.S. design as do many others. The H.M.S. part stands for  HalbMastwurf Sicherung and translated it means Munter Hitch Securing, a munter hitch or wider double munter hitch fitting into the wider part of the ‘pear shaped’ karabiner making it a more versatile piece of equipment. It can be used as a descender itself with the munter hitch or double munter hitch if you don’t have a figure-of-eight descender.

Head Protection

It is always wise to wear a helmet when climbing or abseiling; this generally protects you from debris dislodged from above either by yourself, the rope or others.

The Technique

As there is a certain amount of technique and coordination with abseiling a reasonably smooth face of about 60ft (18m) angled at about 10 degrees from the vertical is good for learning. There are two ways to lock the figure-of-eight descender, the first is to cross the rope over the descender to the other side, this can result in trapped fingers for beginners as they try to hold their weight with the rope and not the descender. The other is to hold the rope out to the side at arm’s length to descend and bring your arm around to your rear to lock; or as they say in the military ‘To stop, thumb up your bum’! The latter method is the most balanced and controllable; it is also the same method in reverse for abseiling forwards, but to stop you bring your thumb to your belly button. The descender will not lock abruptly unless you intend it to; it will give smooth, controlled braking under all conditions directly proportional to the position of your arm. Once you have completed your safety checks and are standing upright on the cliff top, gently ease your way over making sure that your legs are at right angles or slightly less to the rock face and are about 2-3 feet apart to give a stable stance. Descend gently by walking backwards using the friction of the rope through the descender to control the speed. If you are having control the speed of your descent by holding the rope tighter your technique is incorrect.

Safety

Some prefer a safety rope from the top but this can cause balance problems; I personally prefer to hold the rope from the bottom and in the event that the descent is too fast all you need to do is pull the rope tight to lock and then control the descent from the bottom. Of course, this method does not afford any protection against equipment failure but this is so rare as to outweigh this disadvantage over the obvious advantages gained by controlling the descent from the bottom.

Gloves

Wearing gloves is a personal thing. Under normal climatic conditions I never wear gloves for two reasons. The first is that they can get trapped between the rope and the descender if using the front crossover method of control or when tying-off, and the second, is that if your technique is correct the rope will not burn you even on extremely fast descents as it is only passing through your thumb and forefinger as a guide. At no time should it be necessary to grip the rope tightly to arrest a descent.

Safe and happy landings!

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