Читать книгу Canyoning in the Alps. Graded routes in Northern Italy and Ticino, Austria, Slovenia and the Valais Alps онлайн

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Common alternatives to a figure-of-8 are a rack, a bobbin device and a standard belay device. None of these cause rope twisting, but all have their own drawbacks.

Racks

A rack is heavy and pendulous, time-consuming to rig and very difficult to release in turbulent water. Double ropes can be used, but may jam if previously twisted by figure-of-8 use. Racks are not recommended for aquatic canyons.

Bobbin devices

Bobbin devices give a horrible jerky descent in inexperienced hands (bounce = sawing action) and can’t be used with double ropes. Bobbin devices with an automatic brake (such as the Petzl Stop) provide the most control over any device, but require two hands to operate – not always easy in high water.

Belay devices

Standard belay devices are cheap, lightweight and can be used with double ropes, but controlling speed is difficult and they are easily lost when unloading them in turbulent pools. Belay devices are not recommended for canyoning at all.

In addition to these is the Kong Hydrobot, another specialist canyoning descender, currently unavailable in UK high streets. It is essentially a single-barred rack – much less cumbersome than a standard rack and certainly much easier to rig and release. A central bar keeps double ropes separate, reducing the chances of jamming if twisted. However, it is dangerously slick when used with new or small-diameter single ropes, and applying extra friction or stopping mid-descent is not at all easy or reliable. Use the Hydrobot with caution.