Presentation on theme: "Rappelling Techniques ALERT Cadet Alpha 3 rd California Jason Kim March. 2006."— Presentation transcript:
Rappelling Techniques ALERT Cadet Alpha 3 rd California Jason Kim March. 2006
Rappelling Qualifications Written test - Cadets must score 70% or better to receive a GO Knot test - Cadets must correctly tie the following knots, each in 30 second or less: bowline with overhand knot, square knot with two overhand knots, prusik knot with overhand knot, and bowline with overhand knot. Rigging test - Cadets must correctly rig a Swiss Seat Harness and Figure Eight Follow Through knot for rappelling operations within 5 minutes. Command & Control - Cadets must be able to issue commands and hand & arm signals, and correctly perform all procedures controlling rappellers. Hook-up test - students must inspect 2 hook-ups, each within 10 seconds, and identify any deficiencies. Equipment inspection- Given 5 items of equipment. Must inspect all equipment and identify unserviceable items within 2 minutes, Cadets are allowed one re-test per exam. Cadets that fail a retest will be disqualified from this expedition.
Double Fisherman Knots (used to tie the ends of two ropes together) The double fisherman knot is used to tie the ends of two ropes together (ie: to rappel) or to join a single cordelette into a loop (ie: prusik loop) Coil the end of the rope twice around the second rope, crossing over the first coil to make the second one, then pass the end thru the coil. Repeat these steps with the second rope on the opposite direction. Double fisherman Single fisherman Knot
Clove hitch The clove hitch is used to clip into a carabiner attach to an anchor without actually tying a knot, easy to adjust the length without unclipping. Easy to undo. In the middle of the rope create two loops in opposite side, overlap them and insert them in a carabiner. Or at the belay pass the rope thru the carabiner, take the loose end from under the rope tie to your harness, create an opposite loop and clip it into the carabiner.
Munter hitch The best friction knot, better friction then any belay device but has tendency to create kinks in the rope. Excellent method for belaying and lowering. The munter is reversible. Twist a coil on the rope, then fold the lower strand over the upper strand, clip it into a carabiner. Can easily be transform into a clove hitch. In rescue situation the Munter hitch combine with the blocking knot will keep the system releasable.
Prusiks It will allow you to climb along a rope, to set up a z-pulley system, to belay yourself while rappelling. The original prusik is multi directional (must be 2 size smaller of the rope that its wrap around), many variation of the prusik knot are not multi directional. Wrape the prusik around the rope. 2 to 3 time or more depending the condition, icy, wet, new or old rope.
Blocking (Mule) knots Also call Mule knot. A very important knot. You can not perform a Z pulley system, a lower with a knot pass, a load transfer or many other rescue system without this knot. It is a must know. It will allow you to keep all your options open.
Figure-Eight Figure-Eight on a bight: you can tie a figure eight in the middle of the rope to make a loop for clipping into an anchors Figure-Eight Follow- Through: Tie a simple figure-eight knot in a rope, then run the end of the rope through harness you want to attach it, then trace the end of the rope back through the figure-eight knot.
Water Knot Even if most slings theses days are sawn you must know how to do a water knot. Seldom slips once been tightened by weight, but can be very difficult to untie. Back it up with safety knots.
Z Pully System: (pictured right) The basic rescue technique in case of a crevasse fall is the Z pulley system, which allows you to pull your friend out without the use of extreme force. Building the anchor remains the most complex part of the rescue (judgment of snow quality, direction of pull, type of anchor have to be decided). The Z pulley requires a minimum of gear: 2 locking carabiners, 2 regular carabiners, 2 cordelettes (1 long, 1 short), 1 sling. You must know the following knots: Prusik, bachman, munter hitch and blocking knot. Prusick Knots Blocking Knot Bachman Knots Munter Hitch Smalles t angle when pulled 1P (50lb) 4P (200lb) 1P 2P 1P 4P 1P 2P
Safety Checks Double Back all systems (anchors and knots) Double Check all systems (buddy checks) Wear boots, gloves, and helmet Re-tighten the overhand knots at each rappel Use standard check-list to check all systems