Re: [Mitchpee] Weird Malfunction
Mitchpee wrote:
Here is a strange malfunction from Bridge Day 2 years ago that I finally found some footage of. I apologize for the sound but I didn't feel like editing it so just mute it.
For the longest time I thought I had a line over but from outside footage it appears to be from the other guy's burble. We did open too close to each other due to us not taking the right delays. I think this really highlights the importance of correctly stacking 2 ways due to obvious burble interference. Definitely a strange malfunction and could have different consequences if on a lower object or a solid object.
https://vimeo.com/126334044
Looks like either an inadvertent SAT related asymmetric collapse or a front riser dive induced asymmetric collapse. As stable as BASE canopies are, they are still "surfing" or "planing" on/through the air.
SAT is a inertia separation event. The common flight orientation of a ram air wing is the pilot and wing flying the sam direction (both +), in a SAT the wing and pilot have opposite directions relative to the air (+ and - if you were to plot then). The wing creates lift as it orbits around the CG of the pilot/wing, and if the SAT is unstable it can cause the AOA of one side to become negative, making it collapse. Note that this is different from a deep spiral, in a spiral the pilot and wing are still going the same direction through the air and follow a spiral pattern down. In a SAT maneuver it is a helix, the pilot and wing orbiting opposite sides of the CG. It is done intentionally as a standalone maneuver or as an entry or exit to different maneuvers in paragliding. In skydiving a lot of malfunctions can create a SAT like flight pattern. In this video it looks like the SAT-looking spin is the result of the collapse, not the cause of it. If I had only the video to go by, I would say the pilot yarded down on the front riser before the wing was flying and while the brakes were still stowed.
EDIT:Belay that last, yeah it looks like the downwash from the downrange jumper could have cause that collapse. I stop-framed and I did not see any riser input. It's amazing how much air an opening canopy drags with it before it establishes flight.
