What happens to the strength of the Alpine butterfly knot if pulled end-to-end?

The Alpine butterfly knot is designed to maintain a significant amount of its strength even when subjected to loads. When the knot is pulled end-to-end, it experiences certain structural changes that can impact its overall strength. Research indicates that the strength of the Alpine butterfly knot decreases to approximately 57% when subjected to end-to-end loading. This reduction occurs due to the specific geometry of the knot and the way the fibers of the rope interact after being manipulated into a knot formation.

Understanding the strength retention of knots like the Alpine butterfly is crucial in rope rescue operations, as it informs rescuers about how much load they can safely apply. It's also essential for ensuring the safety and effectiveness of the knot in practical applications, such as anchoring or creating a secure loop in a rope system. The decrease in strength serves as a reminder that while knots are essential tools in rescue scenarios, their characteristics can significantly influence their performance under load.