Joints
We have traditionally used box joints but the rectangle ends degrade the material in the transitional area. It is thus best to use a multiple cross point stitch (i.e. 4-point cross stitch or 3-point cross stitch) as they have superior efficiency and twist flexibility. [3]
Knot Strength
Lines will first fail at the knot. The following table is adapted and expanded from Poynter (8.5.2):
| Knot | Reduction in T.S. Percent | Source | Use | Source |
|---|---|---|---|---|
| Overhand | 55 | 1 | ||
| Square | 50 | 1 | ||
| Bowline | 40 | 1 | Pilot chute bridles | 1 |
| Splice | 20 | 1 |
How-To Tie Knots
Spectra Line Slip-Resistant Knot
Tools
T-handle bodkin: t-shaped wire that is used to finger trap lines. You can easily make your own with some wire, a small PVC pipe, and duct tape.
Resources
[1] Dan Poynter, The Parachute Manual: A Technical Treatise on Aerodynamic Decelerators, Third Ed.
[2] Richards, Knot Break Strength vs Rope Break Strength
[3] Ewing, Bixby, and Knacke, Recovery Systems Design Guide