Page 148 - Rappelling

weight of the rope itself adds friction to the system
at the beginning of the rappel, which can be huge
for a big drop of over several hundred feet. As the
caver approaches the bottom of the rappel, there is
relatively little weight from the rope, and more fric-
tion can be easily added mid-rappel by engaging
additional brake bars.
Another big advantage of using a rappel rack
in a dirty/muddy environment like caving is that
the system has no moving mechanical parts that
can become inoperable when caked with dirt or
clogged with mud. Some cavers use a file to carve a
small groove in the top brake bar to keep the rope
aligned and centered, and manufacturers also make
brake bars with grooves in them. When rigged cor-
rectly the rope should not rub against the top of the
frame, as this causes wear to the frame. Brake bars
are available in both aluminum and stainless steel.
Stainless steel is much more expensive but far more
durable in the long run.
It is important to note that when using a rap-
pel rack, the fireman’s belay backup will not prove
effective, especially if there is a good amount of
rope between the belayer and the rappeller. The rappel rack.

Caving

he National Speleological Society (NSS), with over 10,000 members, is the largest organiza-
T tion in the United States that “encourages responsible management of caves and their unique
resources; and promotes responsible caving.” The NSS website, www.caves.org, is a good resource
for information on clubs, training, safety, techniques, and conservation.
The longest vertical drop of any cave in the world is deep within the Lukina Jama cave, in Croatia,
requiring a rappel of 516 meters (1,692 feet).
The deepest cave entrance pits are located in Mexico, the longest being the El Sotano del El
Barro cave, requiring a rappel of 410 meters (1,345 feet), with a close second being the famous
Golondrinas pit at 376 meters (1,233 feet), which is also popular with base jumpers because the pit
widens as it deepens, from 160 feet in diameter at the top to 445 feet across the narrowest dimension
of the great room at the base.

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