HMA Lines

[garywainwright 0]

Does anybody have any idea on how long these lines are lasting?

http://www.garywainwright.co.uk

Instagram gary_wainwright_uk

[grosfion 0]

depends if you have te 160 or 200 lines. I was told that the 200 last for 800 to 1000 jumps..
blues
Marcus

[cobaltdan 0]

i would be concerned about recommending 800-1000 jumps.

to be on the safe side it should be more like 400 jumps provided with proper care.

sincerely,

dan<><>

Daniel Preston <><>
atairaerodynamics.com (sport)
atairaerospace.com (military)

[grosfion 0]

do you use HMA lines on any Atair canopy???

[cobaltdan 0]

no, not currently.

but we were the original manufacturer of the nitro, which precision has resurected and renamed the nitron. this is where precision got the idea to use hma.

i have safety issues with hma, all of which have been voiced in a previous thread.

sincerely,

dan<><>

Daniel Preston <><>
atairaerodynamics.com (sport)
atairaerospace.com (military)

[grosfion 0]

Just got the info from Pascal former designer from Profile Research and now owner of High Performance Research. I think they introduced the HMA lines (now Technora Lines). Let's see how the Blade is...
M

[crazy 0]

Quote

but we were the original manufacturer of the nitro

You guys crack me up. two years ago, you claimed that you were not familiar with that canopy, you even asked me who is the manufacturer. Later on, you gave me a follow up where Stane claims that, 4 years earlier, he built 2 prototypes of the nitro, for Klaus. Now you claim that you were the "original manufacturer of the nitro". Are you still talking about these 2 protos from 96? Or did you actually manufacture the final product?

Quote

which precision has resurected and renamed the nitron.this is where precision got the idea to use hma.

i have safety issues with hma, all of which have been voiced in a previous thread.

Well, i don't think that the nitro died. Klaus Schenk's creation is still alive, he survived through his designs and his genius is still recognized by quite a few people.
People have been jumping these canopies for some 5 years now, without special incidents. Of course lines break, but spectra steering lines can break after 100 jumps as well (it really happened). There is no evidence that HMA (or technora) lines have an unusual rate of failure in skydiving (if someone has, please tell me). The horror stories from the paragliding world have to be put back in their own context. If HMA was so unsafe, it wouldn't be used for marine applications (sails, ropes), extreme sports (rock climbing, paragliding, skydiving), aerostats, aerospace applications, submarine applications... My feeling is that there is a good feedback from many types of applications, no alarmist report from skydiving, few (identified) problems not necessarily relevant to skydiving.
Apart from this, i must say that i really like the fact that there is no significant change in the length of the lines. With 1 jump or 200 jumps, the openings and flight characteristics are almost the same. For my needs it sounds like a very good product, much better than spectra.

--
Come

[GroundZero 0]

HMA lines ...

Please accept comments from only those with experience... we have seen numerous linesets pass 1000+ jumps, (many of those were in the harshest conditions..desert southwest, USA).

First a bit of technical for you chemists out there...
_______________________________


Technora is a para-aramid fibre independently developed by Teijin, which
has been commercially available since 1987. It has high tensile
strength, high modulus and excellent resistance to heat and chemicals,
especially acids and alkalis.

Technora is made from copolymers and is produced in the different
process from PPTA(poly-paraphenylene terephthalamide)

Aramid fibres are a type of nylon of which the molecular structure are
comprised of linked benzene rings and amide bonds.

The U.S. Federal Trade Commission (FTC) distinguished these fibres from
conventional aliphatic polyamide fibres, i.e. nylon fibres, in 1974,
collectively referring to aromatic fibres as "Aramids." In 1977, the ISO
similarly included this name in its listing of synthetic fibres.

As is described in this technical guide, Aramid fibres differ greatly
from conventional fibres (nylon) in both their properties and
applications. Aramid fibres are broadly classified as either
para-compounds in which the molecular skeleton is generally linear, or
meta-compounds with a zigzag skeleton.

Characteristics

(1) High tensile strength
The tensile strength of Technora is 28g/de(24.7cn/dtex,350kg/mm2), which
is 8 times as strong as steel and 3 times as strong as fibreglass,
polyester and nylon of the same weight. This property will serve
significantly to reduce weight.

(2) Fatigue resistance
High tenacity fibres generally show a loss of strength against repeated
abrasion, flexure and stretch, Technora has excellent fatigue
resistance, as compared to the other high tenacity fibres.

(3) Dimensional stability
Technora has a stiff and highly oriented molecular structure which leads
to a high modulus, low creep and low stress relaxation. Due to its low
thermal shrinkage, it has good dimensional stability.

(4) Heat resistance
Technora has a decomposition temperature of 500C. It can be used at 200C
for long periods of time and, even at 250C, it maintains more than half
of its tensile strength that was measured at room temperature.

(5) Chemical resistance
Technora exhibits high resistance to both acids, alkalis and organic
solvents. It is also resistant to sea water and steam.


Mark Cole

Sales Manager Industry
Achner Weg 6
88316 Isny
Tel: +49(0)7562 98 11 45
Fax:+49(0)7562 98 11 00
WWW.Edelrid.de

_______________________________________-

I was later alarmed by a "claim" coming from a competitor that there was a problem/grounding on paragliders.. so I asked the manufacturer...

.............................................

-----Original Message-----
From: Chris Martin [mailto:chris@precision.net]
Sent: Friday, September 13, 2002 5:12 PM
To: Mark
Subject: Re: Aramid


Mark,

Thanks very much. I have heard that in Germany this line has been banned
from use in paragliders, is this true or is this a rumor? Apparently,
it is due to failure caused by UV exposure.

Thanks,
Chris
......................................
and the reply...

"Morning Chris,

No, this is a rumour, we are selling a lot. The unsheathed version goes
into competition gliders and the sheathed version more for the general
gliders. Maybe you are thinking of PBO which is very UV sensitive even
with a sheath we had very bad test results. Be assured we are not
selling you anything that is banned here!!

Best regards

Mark"
>>>>>>>>>>>>


Be very watchful of claims made by persons who are not knowledgable of their subject...

We've had terrific results with HMA lines... do remember, anything can and will fail, but our experience with this line has been exceptional with respect to both performance and durability.

With respect to the Nitro/Nitron... I personally feel this canopy will grow to be the most popular canopy ever manufactured. The Nitron is the exact canopy of the Nitro. This is the only design that did not receive any "tweaking" by Precision. (Note: EVERY other canopy built and marketed by us did receive some changes after we started jumping them. Only the Nitro, was a perfect, completed design when it arrived.)

If you have not jumped the Nitro/Nitron, you're missing out!

Watch for the newest design in higher performance coming soon from the same design team!

Chris Martin
Precision Aerodynamics, Inc.


Let's start substantiating our vague claims (especially when referring to a competitors products)....geez!

[cobaltdan 0]

chris,

we were making prototype canopies with hma long before you heard of the stuff. i have since a couple years ago received quantity samples and full technical papers on technora direct from the japenese manufacturer teijin. whereas they have made a great improvement upon previous material, i still have some founded reservations. as such we will simply have to agree to dissagree.

sincerely,

dan<><>

Daniel Preston <><>
atairaerodynamics.com (sport)
atairaerospace.com (military)

[grosfion 0]

Quote

i still have some founded reservations. as such we will simply have to agree to dissagree.

can you let us know about our concerns in more detail or did I missed out something? Do you have any examples were you had problems of the lines? Do you know any cases of accident involving the lines?
thanks
Marcus

[roq 0]

for example see accident thread
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&safe=off&th=176bbc307a8105b9&rnum=7
"accident with a Canopy with hma lines"

roq

[Kirils 1]

Here, here! I worked with Continental Tire and evaluated HMA cord. It is a dream... far superior oxidative resistance, strength and deformation characteristiscs as compared to nylon or dacron.
HMA is the wave of the future...just bulk it up some...

"Slow down! You are too young
to be moving that fast!"

Old Man Crawfish

[eames 0]

From what I was able to parse from that thread he was jumping an EXTreme 99 (FX or VX, I couldn't tell). At least historically, these canopies are lined with Vectran, not HMA.

Jason

[crazy 0]

Oh my, this is a reference! I have to quote it here:

Quote

i ve heard from a friend, that there was an accident in perris where a
steering line broke in a hook turn.
is that right. did anyone heard about it?
what kind of canopy was it?
how is the skydiver?

Of course no confirmation of this claim. This is a very bad case of rumor mongering indeed (there are much better stories on urbanLegends.com). Even the rumors about HMA lines banned from the paragliding industry were not as pathetic as this one.
Are all the safety issues about HMA line as convincing as this one?

BTW, in Perris, mid septembre (+- 1 week), a steering line broke. It was a spectra line with 100 jumps. Is this enough to ban spectra?
--
Come

[roq 0]

see germany thread http://groups.google.com/groups?hl=en&lr=&ie=ISO-8859-1&q=Nitro%2Bhma&btnG=Google+Search&meta=group%3Dde.rec.sport.fallschirm

Like I know the spectra lines can break when are cut or with great shock. I believe in the technological evolution and that the current lines AHM is good an reliable, but were not in the past.

roq

[prost 0]

I don't think this thread is going to be of any use to most of the readers of this forum as it is not written in English.

[roq 0]

translate with http://babelfish.altavista.com/tr

roq

[ramon 0]

I have read all the responses.

I have also seen a big boy jumping a xaos 21 135 have 6 lines break (that was a fantastic malfunction from the ground). They guy most probably was exceeding the max suspended weight of the canopy. About 200 people witnessed it as it was during the Texas state record attempts.

This was posted here before and can be found if you search the forums.

I never heard anything else about it (reasons or causes, circumstances etc).

ramon

"Revolution is an abrupt change in the form of misgovernment.", Ambrose Bierce.

[crazy 0]

Great story. As altavista is a pain in the ass to translate a newsgroup, here is a short summary of the beginning of the thread (thanks to Marcus):

- 1st post: Frank Besler (FB) claims that the FAA grounded all the nitros until the brake lines are replaced with spectra lines. The reason is an accident in Perris where a line with 250 jumps broke in a hook turn.

- 2nd post: Pascal Lavielle (from Profile Research), after rebuking FB for his wrong info, explains that the guy had replaced his original lines (HMA 430), which had more than 1000 jumps, with much thinner ones (HMA 200). He also claims that, for reasons he wouldn't explain, the canopy and lines were not maintained by Profile Research or any authorised dealer.

- 3rd post: Frank Besler corrects his own post: don't replace the lines, the broken line was cannibalized and didn't respect the manufacturer's requirements, the only grounded nitros are the 30 which were stolen to PR.

I skip the other posts in the thread, not sure if there is any real info there, apart that there was 1 reported broken brake line with HMA 360, which is the reason why Profile Research upgraded to HMA 430, more than 3 years ago.

So much for this horror story. It's still rumor mongering. Yes, there was an accident, but as soon as you check the facts, it's quite harsh and unfair to incriminate the line. I understand that lines breaking during landing are really scary, but please check the info before spreading rumors. If a skydiver goes against all the manufacturer's recommendations, makes stupid modifications and doen't maintain his equipment properly, he is the only one to blame in case of failure.

Anyway, even though the HMA 430 was apparently good enough, as far as i know, now HiPeR use HMA (Technora) 750 for the steering lines.

bb
--
Come

[roq 0]

I didn't diffuse rumors. I just answered to somebody that asked concerning incidents with hma lines, indicating the places where the subject was spoken, for each person to read for itself, nothing else.
In whole the case, I always say that is known that the old hma lines had less resistance to the abrasion that the dynema or spectra lines.
I don't have anything against lines of any type, but there are some dozens of canopys with HMA and there are thousands with spectra. Check the incidents with some and with others

roq

[alan 1]

Quote

From what I was able to parse from that thread he was jumping an EXTreme 99 (FX or VX, I couldn't tell). At least historically, these canopies are lined with Vectran, not HMA.

I don't know about the specific canopy you are referring to, but i do know that you can have your FX/VX re-lined by Precision Aerodynamics with HMA. They do what they call an X-Mod to the canopy. It consists of non-cascaded HMS lines, replacement of the stabilizers with their "stabilrib" and replace the slider with one that has lighter brass grommets. I had the X-Mod on my VX and cannot say enough good things about it. Opens better, flares better, more speed (well, at least a little) and seems to glide better. I've probably got over 100 jumps on it now and the lines are showing no appreciable signs of wear.

alan

[alan 1]

Quote

If you have not jumped the Nitro/Nitron, you're missing out!

I'll back Chris on this. I've been getting some jumps on a 120 and 135 with an exit weight of 220 to 225# and they are just the nicest general purpose HP canopies. You probably won't see anyone winning the big swoop competitions under them, but they are superb for everyday fun jumping for an experienced canopy pilot that wants performance without going to an x-braced class canopy.

alan

[roq 0]

I was to see and to compare the new lines technora, and I was very convinced that are in fact a good option for new HP canopys without cascade lines.

Technora 160 (about 400 lb) with 1mm diameter have half diameter of the spectra 550 lb
New Technora is Impregnated Line that gives maintenance of the length and diameter, light and UV protection, low abrasion, preservation of the trim, low resistance to the advance

A canopy without cascade line have about more 50% of lines than the cascade canopy, but nevertheless has a resistance surface inferior to the advance to a canopy with cascade lines with the double of the diameter.

Roq

[Lavielle 0]

Thank's Come!
in advance: please excuse my bad English! Many skydivers crying arround (if an accident happens) that the material (canopy, gear and so on) caused it. But in most cases it's the skydiver himself. They jump risers with soldered braking rings (very good for steering lines), do not use link protectors or soft links or simply do not take care of their equipment. This means for us we have to consider all these silly behaviours. Now we use 750 Technora steering lines and steel grommets for slider. This normally wouldn't be necessary. Fact is as Chris mentioned: the Technora (HMA) line is an extreme good line (maybe the best at the moment) which other manufacturers cannot overlook.

I know that guy whose steering line broke, unfortunately! He was the first and only case with 430 HMA and the reasons why he couldn't get replacement lines I don't want to explain here.

What Dan said about how many jumps the Technora lines lasts is not correct. Believe me I really offen get Nitros for relining with many jumps. One guy gave his Nitro to us (200 HMA) with 1,200 jumps of the first and only lineset. Just the steering line has been replaced one time.

Just to explain who I am. I worked to years for Klaus Schenk (Profile Research), designer of the Nitro. The year 2000 was a great year for the Nitro. Many skydivers, in the U.S. too, asked to get one. In June 2001 we visited Precision to make a license agreement, so that the Nitro could manufactured and sold directly in the U.S. to keep the costs low. Unfortunately Klaus died of a bad illness in December 2001. Everyone of the team was totally shocked, but we (his wife and 3 friends) decided to go on manufacturing and developing canopies.

Have fun and take care of your equipment!

Pascal Lavielle
High Performance Research (HiPeR)
www.hipercanopies.de

P.S. Our site will soon be in English

[Rdutch 0]

I read on a web site for a vectran manufacturer, and they were defending the line for use for archery, and other application's. And the one thing they said was vectran had had a potential of drying out, this meaning the wax that they coated the lines with, deteriorated with use, Also they mentioned retreating the lines with this wax substantially increased the life of the line. I can't remember the web site, but I would love to find out the company, so I could contact them and get a supply of the wax. I just got a reline on my velocity, and it is a huge difference with the new lines, and when the lines do dry out, my slider likes to hang a lot more, just like Dacron. If you have any idea or know anything it would be much appreciated, and Im sure anyone that jumps vectran would appreciate it.

Ray
Small and fast what every girl dreams of!