The Butterfly coil is a method used by climbers for carrying a rope, such that the rope remains attached to the climber and ready to be thrown or uncoiled. It is most useful when one can approach an anchor point without needing the coiled rope itself. It is also known as a Backpacker's coil.
Starting with the two free ends in your hands, take 1.5 to two arm lengths of rope and let the ends hang free. Now start coiling the rope one arm length at a time, each time placing the coiled rope into your hand in opposite directions. This means that the rope forms two separate "lobes" (or wings, hence the name). These lobes keep twists from forming in the rope. Once you reach the middle of the rope, just add it to the coil. Ideally you keep the end longer than the rest of the coils to mark it for later.
The alternate method of coiling starts with taking two arm lengths of rope as before. But instead of coiling the ropes in your hands, you loop it behind your neck and coil the rope back and forth behind your neck. Try to keep the middle longer as before.
In order to secure the coil wrap the ends around the top of the coil 1 or 2 times and pass a bight through the top of the coil. Finally, pass the two ends through this bight to secure the rope.
This completes the coil, but you can attach the rope to yourself with the following process. Take one end in each hand fairly near the coil. Place the coil behind you with an end going over each shoulder. Pass the ends under your armpits and cross them behind you and behind the coil. Join them in front of you with a square knot for a hands free method of carrying the rope.
- "Rock Seconding School Student Manual". July 2006. http://rss.cmcschools.org/manual.htm#standardsmiscellaneous. Retrieved 2006-10-19.