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Where the theory applies
Loop — mid-line

Alpine Butterfly

Interlock · Climbing

Does not pick a knot

This page does not pick a knot for you. DNA, molecules, quantum braids and vortices stay off Decide.

Finished structure

No drawing of this exact knot yet. The written steps are the reference.

Failure modes

When this family fails, it fails as these. The recovered end still outranks the name.

Alpine-butterfly family

A mid-line eye that can take load in three directions.

  • !Twists not nested — the eye distorts under side load
  • !Tied as an overhand on a bight, which will not take three-way load
  • !Eye sized after it was already loaded
Fails when
  • !The lifted turn was laid over the other turns but not tucked under them, so it slides straight out as the knot comes off the hand.
  • !The turns separated while sliding off the hand and the tuck came out of place, leaving loose coils instead of a knot.
  • !It was set on only the loop or only the standing parts, so it sits twisted and can change shape under its first real load.
Geometry
  • Wrong wrap order

    Body inverts into a slip loop

    Fingertip turn must wrap around the other two before it leaves the hand · step 02

  • Twisted body never loaded on all three parts

    One standing part slips through under load

    Dress by pulling the loop and both standings · step 04

  • Used as an end-loop

    Wrong job — a bowline or figure-8 would untie easier

    This is a mid-line loop, not an end-eye · step 01

If you saw this
  • Loop distorts or one standing part slips through

    Check

    • ?Square body
    • ?Loop standing perpendicular
    • ?Both standings leaving opposite sides

    Then

    • Untie and retie the hand wraps
    • Load all three parts to dress
  • Wrong wrap order

    Check

    • ?Body inverts into a slip loop
    • ?Inspect step 02

    Then

    • Retie. Do not dress a defective structure and call it seated.
  • Twisted body never loaded on all three parts

    Check

    • ?One standing part slips through under load
    • ?Inspect step 04

    Then

    • Retie. Do not dress a defective structure and call it seated.
  • Used as an end-loop

    Check

    • ?Wrong job — a bowline or figure-8 would untie easier
    • ?Inspect step 01

    Then

    • Retie. Do not dress a defective structure and call it seated.
This failed — start Diagnose

What holds it

  • ·A mid-line loop is tied on a bight. Both standing parts stay load-bearing.
  • ·Alpine butterfly and bowline-on-a-bight are different geometries for the same job class. Invariants do not rank them.

What topology does not predict

  • ·Direction of pull (one standing part vs both) is mechanics, not knot type in the Jones sense.
  • ·No working-load table is attached here.
  • ·Capsizing under ring load is a physical defect, already a Diagnose story.

Not for

  • ·An end-of-line terminal eye
  • ·Using this page to override a Decide elimination
  • ·An end-loop (use bowline / figure-8)
  • ·A loop you will tie and untie every five minutes in stiff hawser

Same pattern, different job

No sourced twin among these knots. Related knots stay on the Library card.

Sources