Alpine butterfly knot

The Butterfly Loop, also known as the Lineman's Loop or alpine butterfly loop, is a "non-jamming loop on the bight", a loop which may be tied in a rope with two fixed ends, and can take strain from both ends of the original rope, and from the loop. The addition of "alpine" to the name appears to be fairly recent and superfluous.

Contents

1 Usage 2 Advantages 3 Disadvantages 4 See also 5 External Link

Usage

The Butterfly Loop is used by mountaineers to attach climbers to the middle of a rope, such that they have room to move around even when the main rope goes tight, and they can be supported in either direction from the main rope. The loop is typically attached to a climbing harness by karabiner

It can also be used to isolate a worn section of rope, where the knot is tied such that the worn section is used for the centre of the loop.

Advantages

• Does not reduce the strength of the rope by very much
• Will not slip (after initial settling)
• Allows for the knot to be loaded three ways (each end of the main line and by the loop)
• Relatively easy to undo after loading (more difficult if wet)

Disadvantages

• Difficult to tie one-handed
• Requires some training/practice to master

See also

• List of knots

External Link

• Butterfly Loop