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rapaz

Aramida tapes instead nylon on rounds

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So you're talking about using an aramid, in particular Kevlar if talking about older round reserve canopies like the National Phantom.

I am guessing that Kevlar was used because for a given bulk the tape has more strength. Particularly useful when upgrading a canopy without making it much bulkier than it was before.

1/2" wide Kevlar tape as used in skydiving is rated at 550 lbs (MIL-T-87130, Type 1, Class 2 style, according to ParaGear), while it takes 1" wide Type III binding tape to be rated to 525 lbs. I don't know the thicknesses offhand, but both are fairly thin, the Kevlar perhaps thinner. As for weight, Poynters says the maximum allowed ounces per yard is .30 for the 1" nylon, compared to .09 for the 1/2" Kevlar.

So again I'm not sure of bulk exactly, while the weight is about one third for a similar strength.

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I know very few rounds that are reinforced with kevlar tapes.
Most emergency rounds have type 3 or type 4 tapes as radial reinforcements.

Kevlar is great when you want a canopy that is super strong and has to withstand high deployment speeds.
Martin Baker uses Kevlar tapes on their ejection seat rounds...

Aramida helps to decrease the chance of inversions while deployment. Pioneer had a big problem while testing the K-xx Reserve (a 20 ft. in diameter :S). It blew up as they used "normal" tapes as reinforcement, but solved the problem while using Kevlar instead of Nylon tapes.

The only downside of Kevlar is, that it´s impermanent against UV light. So when you leave it in the sun it will loose it´s strenth. It´s also quite expensive and not very easy in production.

Cheers
NV1

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Aramid (e.g. Kevlar) was fashionable back during the early 1980s because it offered the best strength per bulk/weight. Kevlar was also the first zero stretch material for parachutes. Zero stretch can be a disadvantage during hard openings, because it does not stretch to help absorb opening shock.
Kevlar was part of the whole drive to downsize skydiving gear during the 1980s, that era also saw tiny round reserves, (e.g. Pioneer K-20) being jumped by stupid, fat, white men. Fortunately acid mesh grounded most of those tiny, low-speed round reserves.
The down-side is that Kevlar is rapidly degraded by sunlight and friction. It also has a nasty habit of abrading any other material near it.
Strong Enterprises used Kevlar reinforcing tapes into their tandem reserves for many years (30-ish), but their reserves were limited to 20 deployments.
Better materials have been developed since: Spectra, dyneema, High Modulus Aramids, Vectran, etc.

Now we rarely see Kevlar outside of round chutes packed into ejection seats. Many of them are on a 2 or 3 year repack cycle.

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Dear Wendy,

Pioneer K-20 reserves were designed for your petite ... er ... anatomy.

Rather I was making sarcastic comments about stupid, fat, white men who jumped them.
To be fair, I also made sarcastic comments about stupid, fat, white men jumping Micro Raven reserves.

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Hi Rob
Excellent answer to the thread question.

Unfortunately a guy you know had other view about Kevlar usages>:(B|. See below what kind of answer has been found in his "senior" rigger exam answers.
I knew that was wrong but I double checked with a major manufacturer who told me that Kevlar was not used on crossbraced canopies and nowhere else in modern equipment.
Could you spot other mistakes ?
««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««
MATERIAL IDENTIFICATION

NUMBER ITEM MBS USED FOR
1 TYPE XIII 7000LB MILITARY HARNESSES
2 SUPERTACK 90LBS HAND TACKING
3 SPECTRA LINE 500LBS ZP MAINS
4 1” TUBULAR NYLON 4000LBS CANOPY APEX ON ROUNDS
5 KEVLAR 750LBS CROSS BRACE CANOPIES
»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»»

Learn from others mistakes, you will never live long enough to make them all.

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1) Type 13 webbing is also used to make harnesses for Racers, Sidewinders and Slimline PEPs.

2) Supertack comes in at least 3 different strengths, ranging from 30-ish to 80-ish pounds. I will have to look up the exact tensile strengths.

3) A long time ago (early 1990s) Performance Designs used to line Sabre 1s with 500-ish spectra suspension line. It was not very durable, shrinking out of trim within a few hundred jumps (300-ish), so I always re-lined with 750 or 825 pound Spectra.

4) Yes, I have seen tubular nylon webbing reinforcing canopy apexes on rounds, but cannot remember the MBS. Can I look that up?

5) Kevlar reinforcing on cross-braced canopies???
Maybe on Excaliburs, but nothing sewn during this century.

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gowlerk

No photo needed. I have several Swift Pluses here to look at. They are one of my favorite reserves.



They are nice to pack but the design shows its age when you actually ride one. The flare sure ain't a PD flare... Since I have just completed inspecting an R7 and R8 they both use kevlar tape.

-Michael

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