How to Tie the Alpine Butterfly Loop Knot
The Alpine Butterfly Knot
The Alpine Butterfly Knot is a secure midline loop knot used to create a fixed loop in the middle of a rope without requiring access to either end. It is widely used in climbing, rescue work, mountaineering, rigging, and general rope applications because it forms a strong, stable loop that can be loaded in multiple directions. Its versatility and reliability have made it one of the most respected loop knots in modern rope work.
Other Names: Butterfly Loop, Lineman's Loop
Alpine Butterfly Instructions
The Alpine Butterfly Knot, listed in The Ashley Book of Knots (ABOK #331), is recognized as one of the most effective loop knots for forming a fixed loop in the bight of a rope. Its symmetrical structure distributes load efficiently and allows the loop to remain stable whether tension is applied to one end, both ends, or directly to the loop itself. This unique characteristic makes it particularly useful for isolating damaged sections of rope (isolating a fray), creating attachment points, or constructing rope systems where multidirectional loading may occur.
For similar knots, see the Double Alpine Butterfly (two loops), the Artillery Loop (inferior to the Alpine Butterfly), and the Dropper Loop (rope).
Key Considerations
Dressing the Alpine Butterfly Knot correctly is vital to ensure the knot performs correctly and all strands are seated neatly before loading. A well-dressed knot helps maintain strength, improves stability, and allows for easier inspection. As with all critical rope knots, it should be checked after tying to confirm the loop is properly formed and the strands follow the correct path through the knot.
Advantages & Disadvantages
One of the key advantages of the Alpine Butterfly Knot is its ability to withstand loading from multiple directions while remaining relatively easy to untie after heavy use. It performs well in a wide range of rope materials and conditions and is valued for its combination of strength, security, and versatility. These qualities have made it a standard knot among climbers, rescuers, arborists, and rope professionals throughout the world.
ABOK #331 - Lineman's Loop
ABOK Numbers: Abok #331, Abok #1053
Clifford describes the Alpine Butterfly by another name, the Lineman’s Loop. These knots are the same, and Ashley’s Book of Knots entries are as follows:
Abok #331,
‘The knot sometimes called the Lineman’s Loop is secure and has an excellent lead. It is also compact and is the neatest of the lot. Of the three I should recommend whichever one is found easiest to tie.’
Abok #1053,
‘Linemans Loop. J. M. Drew was the first to publish this knot, and he is probably responsible for the name. It has an excellent lead and is strong, secure, and easily tied; a better knot in every way than the Harness Loop.’
Disclaimer
The information on this website is provided for educational and informational purposes only. While every effort has been made to ensure accuracy, knot strength, security, and suitability can vary depending on rope type, condition, load, environmental factors, and how the knot is tied. Users are responsible for inspecting their equipment and verifying that a knot is appropriate for their intended use. Do not rely solely on the information provided here for activities involving personal safety, life support, climbing, rescue operations, heavy lifting, or other high-risk applications.
SCB Media Group assumes no responsibility or liability for any injury, loss, damage, or consequences resulting from the use or misuse of the knots and techniques described. Always seek professional instruction and follow applicable safety standards where appropriate.