Canyon rappel
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These are rappelling techniques that are frequently used descending canyons, but may be less common in other fields of ropecraft, such as rock climbing.
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[edit] Rappelling with a Pack
Rappelling with a backpack can be both uncomfortable and dangerous. A large pack can get stuck in narrow positions in the rappel. It also shifts the center of gravity, unbalancing the rappeller. This can make the start of the rappel more dangerous. On a long free rappel the pack will pull the rappeller backwards and can even invert a rappeller.
There are three standard solutions if rappelling with the pack on is concerning. The first is to somehow get the pack down by itself, the second is to attach the pack somewhere to your body where it will not throw your balance off, the third is to use a chest harness. These methods are described below.
[edit] Sending the pack down the line
Clip the pack to a carabiner and slide it down the rappel rope.
- This works best if you are not sending the pack straight down. It is often used when there is water at the bottom of the rappel that is undesirable to swim through with a pack on. The first person in the group usually rappels packless (leaving it with another person to send down after him.) When he gets to the base of the rappel, he will walk out as far as he can in one direction to create an angled descent for the packs. The packs are then zipped down the rappel line and to the person at the bottom.
- Common sense should tell you when you should not use this technique. This technique tends to be slow.
[edit] Attaching the pack to your harness
There are a lot of ways to attach a pack to your harness. The main idea is that you don't want it on your back throwing your weight off - especially if there is any chance you will become inverted. Here are some of the common ways to connect your pack to your harness.
- Clip the pack to a secure position on the back of your harness.
- Using a canyon quickdraw allows the pack to hang freely below the rappeller, out of trouble.
- Note that if attaching a heavy bag, it will pull you from behind, and become quite uncomfortable.
- Using a Safety Tether attached to the front of your harness
- Often times the same Safety Tether that you use to clip into anchors can be used to attach your pack. In some cases, you can even get on rappel and then unclip the daisy chain from the anchors and clip it in to your pack. Allow it to dangle below you as you start the rappel.
- This method is particularly effective on large free-rappels commonly found in canyons. (e.g. the last rappel of Pine Creek Canyon
- Remember, especially for heavy packs, to connect the sling to your bag using at least two attachment points; or use a canyoneering-specific pack with a strong attachment point.
- In waterfalls and for landing in hydraulics, the pack should be kept close to the body, perhaps clipped short to the gear-loop on the non-rappel side. For dangerous landings, the pack should be tied on with a releasable hitch, such as a munter-mule.
[edit] Chest Harness
Using a chest harness will keep the rappeller's chest close to the rope and prevent their pack from inverting them. There are a number of variations here.
- Use a complete body harness (less popular in the US).
- Tie a make-shift chest harness using:
- a sling crossed in the back figure-8 style with the two loops up front clipped to a carabiner.
- a carabiner clipped to one of the pack shoulder straps.
- Clip the carabiner onto the rope with the rope running through the carabiner above the rappel device.
Use caution with a chest harness and a wet rappel. The chest harness adds a second point of contact with the rope and can make escape from the rope more difficult. Do not use a chest harness in a waterfall or when landing in a hydraulic.
[edit] Negotiating Wet rappels
Canyoneers frequently find themselves either rappelling into water or rappelling down a waterfall. This adds a new technical element that can be extremely hazardous.
[edit] Rappelling into water
This is best done by placing a 'biner block at the anchor with the end of the blocked rope just at water level. By rappelling single stranded, the canyoneer will rappel off the end of the rope just as they enter the water. This avoids the swimming disconnect and the perils of dropping the rappel device into deep, murky water.
- If you can't see the water to set the rope length properly, set a contingency anchor and let the first canyoneer down help you adjust the rope length.
- ATS YouTube video showing technique of rappelling off the end of the rope into water.
[edit] Rappelling through water
This can be very hazardous as a canyoneer trapped in a hydrolic can quickly drown. It is recommended to:
- set a contingency anchor,
- rappel single stranded and
- without a top belay.
The contingency anchor will allow canyoneers at the anchor to lower a trapped or injured rappeller. Rappelling double stranded can be disastrous. If the water twists the two ropes around each other, this can prevent descent. Sometimes a twist can pass through a figure-8 device, but a twist will not pass through an ATC device. Should the rappeller rotate in the wind or water, a second rope used as belay will become twisted with the rappel rope and will likewise prevent both descent and ascent.
One should also consider cutting backpack straps short for easy escape from the pack. When in doubt, rappel without the pack and have someone send it down the line. As always, loose hair and clothing needs to be tied back to prevent catching in the rappel device and entrapping the rappeller.
[edit] Adding More Friction
On a skinny rope or with a heavy pack slung off the rappel ring a canyoneer may want to add more friction to their device. Some devices, like the Pirana, allow a canyoneer to add more friction to the rappel rig, but most do not. Alternative techniques include adding a second loop to the HMS carabiner or setting up a Z type rig.
- Use two HMS carabiners instead of one. This increases the surface area of the carabiners and adds more friction.
- Add a 'biner to a figure 8 to increase the tortuous pathway of the rope.
- Munter Hitched Tube device - More friction can be added to a tube device by clipping an extra loop of rope to the spine of the HMS carabiner. This adds more surface area for friction and heat dispersion.
- Z rig - Clip a carabiner into a leg loop and another above the rappel device on the anchor side of the rope. Run the rope down through the leg loop and then up in a Z fashion through the carabiner on the rappel rope. The brake strand is now oriented to increase tension when pulled downward as usual. While this system is probably best rigged prior to initiating the rappel, it can be rigged while on rappel if things get scary. A canyoneer also can opt to add each turn in the Z format sequentially as increasing friction is needed. It is important to note that when using the intermediate state (clipped into the leg loop carabiner only), the brake strand is reversed in orientation: increasing friction is added by lifting the brake strand upward. Once the full Z format is established, by clipping into the anchor line carabiner, this orientation is reversed and increasing friction is again added by pulling downward on the brake strand as usual. As usual, locking carabiners are preferred.
- When using a figure-8, one can use a small upper carabiner clipped through the lower hole in the 8. Be careful the rope doesn't slide against the lock and open the carabiner.
- Munter hitch brake line to leg carabiner - As above, add a carabiner to the leg loop. Tie the brake line to this with a Munter hitch. This will provide lots of friction. As above, it will be difficult to untie and should be avoided in a hydrolic situation.
[edit] Guided Rappels
Occasionally it is useful for the rappeller to traverse sideways while descending. For example, when rappelling down a waterfall, the canyoneer may not want to enter the hydraulic at the bottom for safety or style reasons. Alternatively, this technique may be used to rappel over a pothole rather than enter it. It is possible to traverse on the rappel line, but is usually very difficult to prevent the canyoneer pendulum from finding the lowest point on the arc (ie not where they're trying to go). There is also real danger in swinging sidewise on a rappel. If the rope runs over any kind of ledge or lip, the sideways sawing motion of the pendulum can result in real injury to the rope!
Alternatively, a canyoneer can use a second fixed line to descend at an angle.
- The anchor is set with a 'biner block at the top of the drop.
- The first rappeller descends and negotiates the unpleasantness everyone else wishes to avoid.
- Alternatively, the first rappeller may attempt to establish the guide line anchor from above.
- Throw a pack or pot shot onto the landing zone and secure it by sliding additional ballast down the line.
- Lasso a solid object on the landing zone with a loop or knot.
- Set a drift anchor by floating an open pack or pot shot downstream to a more secure location and then weighting it with additional ballast slid down the line.
- Alternatively, the first rappeller may attempt to establish the guide line anchor from above.
- The first rappeller moves to the desired landing zone with the pull line (now the guide line) and sets an anchor there.
- Using the second anchor, the first rappeller tightens the guide line against the top anchor, but only as much as necessary. Tension in the guide line is transmitted to the top anchor and can cause anchor failure if that anchor is not solid.
- Subsequent rappellers rappel single stranded on the rap line while clipped with a Safety Tether to the guide line (be sure the tether will not interfere with the rappel device). This draws them along the angled guide line to the landing zone.
- After the first rappeller down the guide line, the guide line is tightened once. Do not tighten after subsequent rappellers to avoid unnecessary tension on the top anchor. This can be done quickly by tying an in-line-figure-8 and setting a 1:3 pully system (or 1:5 if doubled).
- After the last rappeller, pull the 'biner block as usual.
- Caution is advised regarding the force on the upper anchor. As seen on the anchors page, increasing the angle of the rappel line drastically increases the force on the anchor. In a simple experiment Sonny Lawrence measured a 2.85 kN (640 lbs) force on the upper anchor resulting from a 200 lbs person rappelling along a 30 degree guided rappel!
- See discussion on ACA forum
- See Cerberus Canyons guided rappel and drift anchors.
[edit] Speeding groups through bottle-necks
Large groups can get quickly backed-up at a rappel station. There are a number of ways to improve group dynamics at a rappel station.
- Every rappeller needs their own harness and rappel device.
- Set up anchor at a position that is easy to access.
- Set a Stein knot below the anchor. This isolates the two strands of rope. One canyoneer can rappel on one strand, while a second sets up on the second strand. The last rappeller must remember to remove stein knot to retrieve the rope.
- Set a simulrap from conventional anchors. Place a knot block and clip the the unblocked side to the anchor. Two rappellers then rap simultaneously, each on a single strand. The two rappers should stay close together, so they do not knock rocks on each other. For the last pair down, the heavier person raps off the block, and the lighter person raps off the heavier. Of the techniques here, this one is the most fraught with the possibility of misadventure. See Petzl page for details and pictures.
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