SkySaver versus Rappelling
Rappelling or abseiling is the technique used to descend a vertical drop that involves a controlled rope system and an anchor point. It is traditionally used by climbers when a cliff or slop is too steep to descend and rappelling is the only safe way down. Rope access technicians also use this as a method to access difficult-to-reach areas for purposes such as maintenance, construction, inspection, welding, or rescue teams. The technique can also be used to evacuate a building, as in the case of SkySaver. Because it involves dangerous heights, rappelling requires an immense knowledge of the sport and several key pieces of equipment. This short video below goes through the essentials of rappelling and is a good introductory course for those new to the technique.
So, we can see that rappelling requires several key skills:
1. ANCHORS In order to rappel off a cliff, at least two anchors are required. In the instructional video above, she uses a tree, but anchors can also be other points such as bolts, or tied-off boulders. Rappel ropes are always threaded through metal—carabiners, quick links, and steel descending rings—rather than nylon slings, which can melt, break, and fail if they are in direct contact with rope.
2. ROPES When rappelling, you use either one or two climbing ropes, which are threaded through the metal anchor material.
3. KNOTS Before rappelling, it is crucial to learn how to tie proper stopper knots at the end of each rappel rope so you don’t end up rappelling off the end.
4. RAPPEL DEVICE The rappel ropes should be threaded through a rappel device, like an ATC or figure-8 descender.
5. AUTOBLOCK KNOT An autoblock knot or a Prusik knot is a safety back-up on the rappel ropes that lets you stay in control, especially on long steep rappels.
6. PULLING RAPPEL ROPES Pulling rappel ropes is not as easy as it sounds. Lots of problems can occur when you pull your ropes, including getting the knot jammed in a crack, the rope catching in cracks or behind flakes, or too much friction to easily pull the rope down. If any of these problems occur you’re going to have a whole new set of problems retrieving your ropes and they’re not going to be fun. For more on rappelling skill, check out: http://climbing.about.com/od/rappelling/a/6RappelSkills.htm
The SkySaver unit, is similar to a rappelling device in some ways but very different in others. First of all, the most striking difference is the device itself. Rappelling traditionally involves use of a complicated harness that takes time to put on and tighten. Even veteran climbers take a couple minutes fitting the harness and making sure everything is attached properly. SkySaver, however, has the harness contained within the backpack and takes just seconds to put on. The familiar look and feel of a backpack make the SkySaver easy to put on and the straps are ergonomically designed to be easy to locate and tighten. In a real emergency situation, the last thing you want to do is waste precious time getting into a complicated harness. Another thing that sets SkySaver apart from rappelling is that although both make use of controlled descent, with SkySaver, the descent is automatic. When rappelling, you usually have some sort of rappelling device which feeds through the rope, causing friction, and you are able to slow your descent. With SkySaver, the descent is all automatic and requires no concentration on the part of the user to ensure a safe speed. The descent drum which is located in the backpack will lower the wearer at a safe speed of 3-6 feet/second (1-2 meters/second).
Similar to rappelling, SkySaver also requires a fixed anchor point that the device can be attached to. In the rappelling video above, the woman uses trees which are firmly planted in the ground. For SkySaver, we strongly recommend having a professional install an anchor into your wall, next to a window which can be used in an emergency. The anchor doesn't need to be as big as a tree, but it certainly needs to be safe, strong, and conveniently located.