http://w w w.brrr.us/safety/ May 23, 2012 Welcome to the Blue Ridge River Runners Safety Page. It has been estimated that an open canoe, swamped, gunwales upstream, in moving water, has the kinetic energy of a Volkswagen Beetle moving at the same rate of speed. A 5 MPH current is a moderate current. Imagine striking a large boulder in a VW Beetle at 5 MPH. Kind of gives you a whole new perspective on what moving water and a stationary rock can do to your boat, huh? Few of us who have been paddling for any length of time have failed to witness the results of such an encounter. Ever notice that the boulder always wins? All too often the boulder becomes wrapped with a combination of high-dollar space-aged plastic and aluminum. It is extremely important that each boater know how to prevent such an occurrence, however, it is not the purpose of this writing to address preventive measures; rather, we are going to attempt to deal with the consequences thereof. The Situation For the sake of this lesson, we are going to assume the case of a sixteen-foot open canoe, with aluminum gunwales and thwarts, and with at least some flotation (air bags or inner tubes). This boat has capsized in a moving current, in the middle of a Class III rapids, and has pinned itself, gunwales upstream, dead center of a mid-stream boulder. The occupants have managed to escape, and are able to assist in their own rescue. Other boaters are at-hand to assist in the recovery effort. One paddler is sitting on the rock against which the boat is pinned. Optimum scenario Ideally, the boat is simply pinned, with little damage, but firmly held in place by the force of the water. A rescuer on one shore throws a rope to the rescuer on the rock. The rescuer on the rock attaches the rope to the far end of the canoe (away from the direction of pull). Several rescuers on shore grab the rope; give a mighty heave, the boat pops off and pendulums to shore. Happy ending. Wouldn t it be nice if all rescues were so simple? Typical scenario In the real world, it is far more likely that the boat has conformed to the rock, and has defied their initial attempt to brute-force pull it free. So, what to do? One popular theory states, If brute force doesn t work, you re not using enough of it. Well, let s use more ropes and more rescuers pulling on the damn thing. Sooner or later it s gotta come off, right? Well, maybe so. Try it, if you ve got the ropes and the people. More typical scenario It s a cold day in the middle of the week, and there s nobody else on the river but you and three or four friends (the rest of us have jobs to go to in the middle of the week), and you just can t get that damn boat to move. So now what to do? To the incredible display of raw muscle power usually to be found in any group of paddlers, add a little brainpower and a few tried and proven techniques. Use the current to help move the load Instead of pulling directly against the current, if we could roll the boat over so that the open gunwales are pointing slightly downward instead of straight upstream, the force of the current might move the
boat upward, reducing the downstream pressure. Steve Thomas, a long-time canoeist and member of the Coastal Canoeists, developed a technique for using the current to assist in raising the pinned boat. His technique has achieved worldwide fame as the Steve Thomas Rope Trick. This technique has saved the day for many an unfortunate paddler, and should be thoroughly mastered by any aspiring canoeist. This may be all you need to dislodge the boat. But then you might still need an additional advantage. Mechanical Advantage Mechanical Advantage is a term describing the use of mechanical devices to multiply the input force by a certain factor to achieve a greater output force. A lever is a good example. By properly applying a lever under a load, a small force on the long end produces enough force on the other end to move the load. Pulley systems can be used to apply mechanical advantage to the task at hand. Hauling systems
System A provides no mechanical advantage whatsoever, but does provide a change in the direction of pull, which may be of advantage. Systems B through F provide mechanical advantages of 2:1 through 9:1, respectively. Each system provides progressively greater mechanical advantages, but require progressively greater quantities of gear and rope. Rigging the pull One of the great things about this sport is that it gives us an excuse to accumulate a lot of nifty gadgets. And among these gadgets we ve hauled down the river with us (or should have) are: Ropes (3/8 or ½ braided or kernmantle Polypropylene or Nylon, 75-150 feet in length) Prusik loops (6-8 MM accessory cord) Carabiners (a whole bunch of em) Pulleys These are the essential parts of several tried-and-true hauling systems. Now we learn how to put the
pieces together. Basic knots Having the right gadgets is one thing; knowing how to use them is another. Below are several very basic knots that each boater should know: Use the Figure 8 knot to put a loop in the end of the line, or to tie two lines together. These knots are very strong, and relatively easy to undo.
The Clove Hitch (not a knot) is used to secure a line to a tree or other object; easy to apply, easy to untie.
The Double Fisherman s knot is used to permanently join two rope ends, or to form the Prusik Loops. Keep several of these loops (in varying lengths) in your kit; they re very handy.
The Prusik, Bachmann and Kleimheist knots will lock onto the standing line under tension, but will slip freely when unloaded. The Prusik will lock in either direction, while the others lock in one direction only. The Bachmann knot has the benefit of a carabiner handle. Additionally, the Kleimheist knot can be formed using webbing slings. The others don t work well with webbing.
The Load-releasing, Mariners and Münter Hitch are used to anchor the haul system, when it may be necessary to release the load gradually while still under tension. The Münter hitch is also an effective belaying hitch for climbing and rappelling.
Here are six different ways to attach the anchor. The Simple Loop and the Girth Hitch are the simplest, albeit the weakest. Multiple wraps or the no-knot method are the most secure. The Z-Drag Also known as the Z-rig, this hauling system is relatively easy to rig, and provides a 3:1 mechanical advantage. The minimum hardware requirements are: Rope(s) Three or more carabiners Two pulleys (optional; the rope can be run through the biner without a pulley, with only a little added friction) Two or three Prusik loops Below are shown two variations on the basic Z-drag.
In A above, the Brake Prusik is used to secure the load while the Traveling Prusik is re-positioned. The Traveling Prusik is re-positioned to get another pull when tie previous pull has run out of rope. Method B uses a friction wrap to secure the haul line, and multiple loops in the haul line to reposition the traveling pulley or biner. Keep in mind that while one pound of pull on the haul end of the line will produce three pounds of pull on the boat; however, for every one foot of movement of the boat, you have to pull the haul end three feet. That s one of the tradeoffs in using mechanical advantage systems. The Piggyback or Pig Rig The Pig Rig combines several of the mechanical advantage systems shown above producing an aggregate advantage of.4:1 or 6:1 depending on the method used. While requiring more gear, it also has the advantage of utilizing two shorter ropes. Tips and tricks
The Prusik-minding pulley keeps the brake Prusik from fouling the sheave. The Snubber system can protect the haulers from harm in the event that the rope or its attachment breaks, by snubbing and re-directing the flying end.
The Taco rig can partially fold a raft; thereby reducing the surface area the current has to work against. The Bottom Line It s great to have all the help you need when you re in trouble, but don t count on it. Be prepared to do the job yourself, or with only limited help. Get some good books. Read them. Really study them. Get the right equipment. Learn how to use it. Practice setting up your rig in your backyard, where you re in control. Don t wait until you re in trouble to find out you don t quite know what you re doing. Better yet, learn from the experts how to avoid trouble in the first place. Remember the old saw: An ounce of prevention is worth a pound of cure. Summary Know the river and its hazards. Avoid accidents if possible, but be prepared for any eventuality. Learn good rescue methods and techniques. Acquire the necessary gear, and carry it with you. Practice setting up the hauls in a safe and controlled environment Above all, learn and practice good boating skills and safe boating habits. And NEVER paddle alone. Acknowledgements The Author has shamelessly plagiarized all of the graphics and many of the ideas contained herein from the excellent book River Rescue by Les Bechdel and Slim Ray. To them go my thanks and appreciation, and my pleas for forgiveness. To Steve Thomas, many in the paddling community (myself included) owe a great debt of gratitude, for the many otherwise hopelessly broached boats that we have been able to recover (and paddle away) using his famous technique. Thank you, Steve. And to you, my long-suffering captive audience, I extend my thanks for your patience, your tolerance
of my aimless rambling, and for your attention (you were paying attention, weren t you?). And no, I will not autograph a copy of this for your kid (unless she s 18 or older and not coyote ugly). Howard Kirkland