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nacmacfeegle

HMA lines

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Is HMA 'legal' in Europe, I was chatting with a packer recently and he seemed to think there was issues with HMA being 'outlawed' due to some problems with Parapents/Paragliders.
He also seemed to think there was some issues with wear characteristics, ie hidden failure, lines prone to busting with zero or minimal signs of wear.
Or is all this packing shed mythology?
Personally I can't see reputable manufacturers providing anything that is in any way 'dodgy', but I said I would ask.
Cya
D
It aint what you fly, its how you fly it!

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I did some searching on the web for it lastnight. Here is one of the several pages I found that compares the different types of lines. Keep in mind when I was doing the search the only people that had info were the paraglider wing mfgs.
http://www.crittermountainwear.com/linematerial.htm
From the way I read it, is it is more durable than vectran, but becareful when sewing it cause it can weaken and it doesn't like UVs. It isn't as durable as Spectra, but it doesn't shrink. I spent like 3 hrs looking at different web pages lastnight, there is quite a bit out there about it, but you have to look under paraglider links.
Kelli

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i was told by a major paraglider designer that hma was not legal in germany. apparently about 12-18 months after it was adopted by a few companies there were enough accidents and fatalities to ban it.
hma is simply another kevlar aramid: #49 as opposed to kevlar #51.(vectran). looking at the fibers spec sheets hma seems less appropriate to use than vectran. it has 1/2 the elongation 2% as opposed to 5% buit also has 1/2 the elasticity and is more horribly degraded by exposure to blue-uv light.
i requested accident reports involving hma from dhv in germany but have not received them yet.
sincerely,
dan

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Dan,
I was hoping to see the results of the Nasa tests first...
but looking forward to the tests from the other space agencies also...
_____________________________________________
"another space agency is performing crossfire tests scheduled mid april. results will not be released till after then"
_____________________________________________
Let's see, NASA tests... just a moment I'll find a quote....
____________________________________________
"5 crossfires were tested by nasa in a windtunnel.
the report should be published next month....
sincerely,
dan"
____________________________________________
Geez Folks!
I'll gladly accept anyones' practical experience to be quoted, but searching for failures in a completely different application... What gives? I think I'll replace the aluminum on my airplanes because Stainless Steel appears to be less corrosive. Paragliders spend HOURS per flight.. we spend minutes per flight. HMA has been demonstrated for a number of years on skydiving canopies. Have you ever noticed that there is no use of Performance Textiles "Soar-Coat" used in the paragliding industry. Soar coat uses DuPont's additive "Solar Guard" to extend the life of this zero-p fabric. Soar-Coat with Solar Guard is used by both Precision Aerodynamics and Performance Designs for their highest performing canopies. This fabric has increased lifespan when used in parachute applications. No paragliding manufacturer has chosen to use it (that I'm aware of...) because it is not designed for that application.
Dan,
As your competitor, I have refrained from commenting on your products and until now, your practices. It would serve the viewing public better if you would wait until you CAN document your statements.
What do I need to do? "In the interest of safety in our sport, I am securing motor vehicle and arrest records of all (insert competitors canopy type here) pilots to demonstrate the nylon/drug relationship"... This is how I read your posts... is it this silly or just me?
Chris

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