Hello everybody.Engineer and new pilot here with zero flights due to no training in current covid situation,i had the luck to try a tandem flight last summer :).
I got the buzz for the sport and perhaps made poor gear choices due to excitement.I bought a secondhand pap pa125 in pa racing frame.I dont have hands on experience with any other paramotors but done alot of research online since. I have come to the conclusion almost all paramotors are lacking in safety and design issues, most of it has to do with the netting and engine mounting.It seems lightweight is what sells and dictates the design.
1.The netting.The pap i have had the same style netting as on the current tinox models.While it is strong you can easily fit a throttle or your whole hand through the netting.I redid mine with tig welded 1,6mm stainless loops and 200kg line strength dyneema with a tighter square netting,you can literally stand on it and the lines are easily replacable at low cost.I could share the build process/pictures/design if there is interest.Many models use weak flexible netting that will of course keep light objects and lines from going in the prop,but offer no real protection for limbs or forces acting upon the net.Other models like the flat top/fresh breeze use strong netting but the line will chafe on the holes and eventually cut.A cut line(netting will wind up in the prop and your going to have a bad day.
2.Engine mounting.From what ive looked,almost all paramotors share the same rubber engine mounts.The rubber mounts are not designed to use in the configuration they are used in paramotors,your literally hanging the engine on some rubber pieces and hope it doesnt sheer off.Even if it doesnt shear it will start to sag and the prop will get closer to the ground.When i got the pap second hand I was wondering why the prop was just touching the ground and not parallel to the hoop.Found out the rubber mounts were sagged and stretched(not cracked yet).I replaced the mounts with new pap ones and after a week its half way there sagging again.One option seems to be to replace the mounts with polyurethane mounts,although these are not available any more,there will be increased vibrations and the fundamental problem of the mounts sheering and engine getting loose still persists.The other more common option is to use a safety line around the mount,while this should keep your engine from working completely loose i would assume it would allow enough movement for the prop to touch the hoop/ground.
Im currently building a engine mount design which is failsafe to replace the standard 30x30 mounts.It would still utlilize the same style rubber mounts so vibration dampening would be the same.But the mount could not fail and the mount would carry the engine weight without sagging.It would be enough to use these mounts as upper mounts and retain the stock rubber mounts as lower mounts.The upper mounts would likely last a lifetime and the lower mounts longevity would be greatly increased due to not carrying the weight anymore.Im building these mounts for myself using a lathe and mill for my own use and testing.But i was wondering if other pilots consider the current mounts as risky as i do,and would be interested to buy these if I would have them manufactured in larger scale?I cant really speak of the price but I would estimate between 60-100euro for a pair depending of manufacturing costs and also if they would be done locally or outsourced to asia.