BASE Mals
Tension knots, canopy reliability statistics, & design progression
By the SQ/AD Team
(version Française ici)
Tension knots could be the scariest and least understood BASE malfunction. Caused by an entanglement of lines during deployment, a tension knot can result in an uncontrollable canopy forced into a high descent-rate turn, stall, or asymmetric stall. The exact causes have remained unclear throughout the 40 year history of BASE, yet most BASE jumpers can tell you at least a couple of things that supposedly contribute.
In an effort to increase understanding of rates of occurrence, we surveyed BASE jumpers in 2019, and conducted a more than year long study during 2020-21. Getting a large enough sample to gather adequate data for strong conclusions may be impossible, but this is a start. Thank you to the jumpers who took the time to answer our questions and contribute to this research.
This is by no means a conclusive study, and is only part 1 of what we hope is a more thorough effort by the community to understand tension knots. It is not easy to reliably create tension knots on-demand using normal packing techniques. Until a phenomenon can be reliably created, it’s difficult to identify major individual factors.
In the short term, we aim to:
Suggest techniques for dealing with tension knot malfunctions
Allay fears about factors that don’t seem to be major causes
Bring your attention to factors which may be significant
While the 2019 survey was useful, the bulk of progress that has been made is the result of two years of test jumps using a variety of gear configurations, sliders, and line plans. Using the information collected during this study, we are endeavoring to develop equipment designs with decreased tension knot potential.
