It’s not a flaw with the wing but I’m taking it out of service until I can resolve an issue with the unsheathed lines that are getting tangled with the keepers. This situation wouldn’t be a problem for a foot launch pilot or even one on a smaller two stroke trike. But… This is a big rig and probably not a configuration the designer considered when putting this wing together.
… pinch/stretch to zoom
This video is an aborted launch caused by the brake and 2D lines tangling with the line keepers on the outer ring of the cage. The unsheathed lines have no “stiffness” to withstand the turbulence and “suck” from the prop.
Part of the problem is that there are two line keepers. Why Terry Lutke did this, I’m not sure but he encourages using both. Also… I noticed that prior to starting the engine I pulled several inches of 2D and brake line to allow me to reach the ignition key. Even if I’m not pulling the brake far enough to reach the ignition , just grabbing the risers and preparing to start, brings the junction of the sheathed and unsheathed lines right up to the keeper where the tangles occur. The “Y formed by the A1 line is at risk for getting hooked on a keeper. Also… The unsheathed lines have little or no tension as it runs back to the wing.. I fear that eventually, that incredibly limber line is going to get whipped into the prop.
There are some things I can do that will help. An electric start button on the throttle would help, allowing me to have most of the slack out of the lines because I would not have to pull line creating slack while reaching for the starter. Also…. The line keepers must be modified to eliminate the possibility of lines snagging at the bottom of the V.
I think, with this large paramotor trike, there is an inherent danger with a thin unsheathed line this close the the propeller, especially during the take-off sequence, when line position and tension can be so dynamic.
I want to note that I did not use the A assist. The A line on the Colorado riser is shorter than other wings I’ve flown. The assist line would have only been about 6 inches long. I wasn’t confident that the A assist would be effective and was uncomfortable with a short A assist tugging on the wing while in flight. Also…., I wanted to feel the new wing during inflation.
One way I’ve thought to fix this issue is by adding 1 meter (maybe more) of sheathed line to the brake and A1 lines where they leave the risers. This will of course, require shortening the unsheathed lines and lengthening the 2DmBR the 2D steering line and the A1 line. This will put stiffer lines around the keepers and move their connection point, with the unsheathed lines, away from the rig where they have been getting tangled. I don’t think this change will have a material effect on the wing’s behavior…
But…. I look forward to Mr. Recek’s thoughts. If changing out a few lines is going to be the best solution. Then, I’m all for it. It’s just a matter of calculating the correct measurements and ordering the line. If he has a better solution…. I’m all ears.