After landing safely under his main, a jumper using borrowed gear found that the metal Rapide® link connecting his suspension lines to his risers had separated, with the bolt end of the link holding the risers and the threaded end holding the lines. Tension was the only thing that held the system together, and any maneuver would have caused it to separate.
Inspection revealed that the threads had not been stripped, indicating that the link had become unscrewed at some point before the jump. Inspectors believe that the opening shock caused the link to spread out. Rapide® links can loosen over time if the barrel nut is not tightened correctly. If the jumper had checked that the barrel nut was tight before jumping, it would have entirely prevented this from happening. It is also possible to cover metal links with clear tubes, which keeps the links properly oriented with the risers and suspension lines and helps to prevent the barrel nuts from loosening.
This incident serves as a good reminder of why it is important for jumpers to perform thorough gear checks before jumping, particularly on borrowed gear with unfamiliar components. If you are not familiar with any part of a parachute system that you are checking, don’t be afraid to ask someone who is.