Sabre 1 120 reline

[flipwithit 0]

This is my 5th sabre 1 120 (WS canopy) and first time relining one since they are harder and harder to find. Any reason to not go with vectran instead of spectra? Our lz is mostly desert style bullshit, so not considering hma.

[parachutist 1]

Vectran life is kinda short. Also it gets damaged near the links quickly, unless you pull the slider down on every jump. Spectra would be my choice

[betzilla 56]

but by the time you see enough damage on the Vectran to warrant a reline (say, 500 jumps, give or take), the Spectra may have gone out of trim far enough to make openings squirelly, so you might reline at about the same # o' jumps either way. Personally, I'd choose Vectran and enjoy factory trim for the whole life of the lineset.

[gowlerk 1,904]

betzilla

but by the time you see enough damage on the Vectran to warrant a reline (say, 500 jumps, give or take), the Spectra may have gone out of trim far enough to make openings squirelly, so you might reline at about the same # o' jumps either way. Personally, I'd choose Vectran and enjoy factory trim for the whole life of the lineset.

I'd agree with this. A 120 is a small enough canopy that line trim matters. On 170s and up it matters a lot less and then I'd go with Spectra. Just my 2 cents. Other people see it differently.

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[parachutist 1]

betzilla

but by the time you see enough damage on the Vectran to warrant a reline (say, 500 jumps, give or take), the Spectra may have gone out of trim far enough to make openings squirelly, so you might reline at about the same # o' jumps either way. Personally, I'd choose Vectran and enjoy factory trim for the whole life of the lineset.

Must be something to do with the area where jumps are made and line life. That's kind of the message I got from a PD rep when discussing with them a few years back. I'd asked why Sigma vectran lines were wearing so fast for DZs close to me (350 jumps). It was something happening with the fine sand dust particles getting in the lines and shredding away. Switch to Technora and we get 650. Spectra doesn't seem to be affected, except for the typical shrinkage.

So for my area I was thinking 450 from a spectra line set before the openings are bad enough to replace, and 350 for Vectran. Maybe all desert areas aren't like my sandy beach area here, but the OP mentioned desert so I figured it might apply

[parachutist 1]

gowlerk

***but by the time you see enough damage on the Vectran to warrant a reline (say, 500 jumps, give or take), the Spectra may have gone out of trim far enough to make openings squirelly, so you might reline at about the same # o' jumps either way. Personally, I'd choose Vectran and enjoy factory trim for the whole life of the lineset.

I'd agree with this. A 120 is a small enough canopy that line trim matters. On 170s and up it matters a lot less and then I'd go with Spectra. Just my 2 cents. Other people see it differently.

Yes everything gets more affected on smaller canopies. Maybe I am biased against Vectran because of the constant need to replace it around here.

[masterrigger1 2]

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Any reason to not go with vectran instead of spectra? Our lz is mostly desert style bullshit, so not considering hma.

I would never reline a Sabre I with Vectran simply because it would open harder. While Vectran does have more drag coefficient to slow down the decent of the slider (which in turn slows the opening), Spectra has more elasticity than Vectran which counts at the bottom end of the opening. This makes it a little more forgiving if you had a hard opening.

I would reline it with my Black 600lb Technora. It would make the openings softer and more reliable and you should get 400-600 jumps out of it even in the desert environment if you take decent care of them.

MEL

Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

[masterrigger1 2]

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betzilla wrote:
but by the time you see enough damage on the Vectran to warrant a reline (say, 500 jumps, give or take), the Spectra may have gone out of trim far enough to make openings squirelly, so you might reline at about the same # o' jumps either way. Personally, I'd choose Vectran and enjoy factory trim for the whole life of the lineset.

I'd agree with this. A 120 is a small enough canopy that line trim matters. On 170s and up it matters a lot less and then I'd go with Spectra. Just my 2 cents. Other people see it differently.

Pretty much what Betsy said... Although I would not install Vectran on a Sabre I which is #4 on the hard opening canopy list.You simply don't want to make matters worse...

With regards as to it matters less on larger canopies; I would disagree. All of the fatalities involving hard openings that are known to me, where were under canopies lined with Spectra. The smallest two canopies were both 120sq.ft while the majority were larger canopies.

Just a few hard openings on Spectra lined canopies from another thread for example:

Sabre2 210 – separated pelvis and shattered femur.
Sabre2 190 – femur, elongated hip rings, dmg to both risers and stitching on cable housings
Stiletto 120 – fatal - torn aorta, no damage to canopy
Sabre2 170 – fatal - torn aorta and broken back
Spectre 190 - fatal - incapacitated by opening
Spectre 190 - fatal - incapacitated by opening, multiple broken lines


MEL

Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

[skydiverek 54]

masterrigger1

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Any reason to not go with vectran instead of spectra? Our lz is mostly desert style bullshit, so not considering hma.

I would never reline a Sabre I with Vectran simply because it would open harder. While Vectran does have more drag coefficient to slow down the decent of the slider (which in turn slows the opening), Spectra has more elasticity than Vectran which counts at the bottom end of the opening. This makes it a little more forgiving if you had a hard opening.

I would reline it with my Black 600lb Technora. It would make the openings softer and more reliable and you should get 400-600 jumps out of it even in the desert environment if you take decent care of them.

MEL

How about relining with Dacron? Keeps trim, slows the slider down due to friction, and stretaches during hard openings.


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[masterrigger1 2]

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How about relining with Dacron? Keeps trim, slows the slider down due to friction, and stretaches during hard openings.

Absolutely, but the added parasitic drag of the bigger lines affects a smaller canopy more than a larger one. It will do three things.
1.Slows the canopy speed wise
2. Pitches the canopy slightly more nose down attitude
3. The combination of the two things above will diminish the flare.

Although you could put a 400lb Dacron on it and resolve most of the issues associated with a larger Dacron.


MEL

Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

[gb1 2]

If someone could get rid of the slider with another opening device, the line manufacturers would be hurting. Would have to get real lucky to replace the slider.

[RiggerLee 61]

I don't buy your argument that vectran would open harder then specter do to specter having greater elasticity. Specter doesn't have a lot of give to it. It sets and has very little give, same with vectran and hma. Even Dacron has a limited amount of energy absorption. I think that whole business is a bit of a myth. I think it dates back to rounds with long lines. If you look at an opening curve you will see a sharp spike where it hit's line stretch then the opening. With a long lined canopy like an old round there is a long distance over which it can accelerate and build up kinetic energy the spike can be pretty big and the peak higher then the opening. The supper stretchy rubber bands lines can help with a momentary spike like that. Keeping in mind that the old type 3 lines had ten times the elongation of dacron. But even that can't help with the actual opening. After that 12 inches of stretch the lines are saturated and all the load goes right through the system. There is a limit to the amount of kinetic energy some thing like that can absorb. Force over distance. Integrate it. Once it stops stretching... that's it. It's done. How much force does it take to stretch the lines on a round that twelve inches? Pulling harder does not count if it only stretches a 1/4 inch. It's force times distance. And then you are not absorbing energy or lowering the peak load. With some thing like dacron how far does a line stretch? 2 inches? And under what load? You're still seeing that load. Doing the math, it's not much help at all. In fact the round canopies I've been test jumping have been lined with specter.

Where does this come from? I think it's secondary issues related to line material. How well the rubber bands hold the lines. The quality of the staging. Friction on the slider and how fast it's pushed down. Shrinkage of the outer lines pushing the slider lower on the canopy reducing it's effectiveness. I think the size thing is real. A canopy that large can put even more hurt on you if the canopy becomes dominant over the slider to early in the opining or if there is a problem with the staging. It's also a product of the higher loads under them. If the guy weighs twice as much there is twice as much energy to be absorbed. If he's falling faster, as big guys do, it's even worse as energy goes up with the square. And with a higher speed you can have more snatch force compromising the staging.

Of all the issues with hard openings I just don't think line elongation is a significant factor. And your own evidence points to specter being even less forgiving. Still I've seen problems with going from specter to vectran or other materials. Example. Guy got a canopy lined with specter relined with vectran. This is back when it was first becoming popular, I think it was a vengeance. Suddenly his openings went to shit. They were not hard but they became radical. Basically the slider was coming down slower and sticking or at least hesitating part way down. This meant that the canopy was more inflated at this point and trying to fly. It would surge forward and radically dive turning hard to one side or the other. The slider being part way down made the canopy less stable in roll and it became super twitchy during the opening. Eventually he had it relined in specter again and it all went away. So there are some weird interplay's that can occur in the dynamics of the opening. If you take an older canopy and put one of these newer line sets on it you should consider your self a test jumper.

Lee

Lee
[email protected]
www.velocitysportswear.com

[masterrigger1 2]

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I don't buy your argument that vectran would open harder then specter do to specter having greater elasticity.

Obviously you have never jumped a canopy with Spectra, lined that same canopy with Vectran and then jumped it.
I have and the difference is what I have previously explained.

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Specter doesn't have a lot of give to it. It sets and has very little give,

Spectra is easily shown that is has more elasticity to it than Vectran by simply putting a piece of Spectra on a line table, put it under load, make a mark that matches the same spot on the table, and then watch the two mark separate slowly. It will do it every time..

Vectran will not do this...
So my statement stands.

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I think that whole business is a bit of a myth.

You need to look into it more.
Dacron lined Mantas open just fine. Put Spectra on one and you will soon see the difference, enough to have to install a nose mod on them.

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Of all the issues with hard openings I just don't think line elongation is a significant factor. And your own evidence points to specter being even less forgiving.

Elongation (or lack of..) is an issue if you have a hard opening would you not agree??
Most people would think so.

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Still I've seen problems with going from specter to vectran or other materials. Example. Guy got a canopy lined with specter relined with vectran. This is back when it was first becoming popular, I think it was a vengeance. Suddenly his openings went to shit. They were not hard but they became radical. Basically the slider was coming down slower

Thanks for making my point.
Vectran will slow the slider down with increased friction from the Vectran material as I previously indicated. The problem is that is has NO stretch to it to speak of. Spectra does.

You were speaking earlier of curves.
If you have 0 elasticity or give to the load, it would be pretty much a straight line would it not??

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If you take an older canopy and put one of these newer line sets on it you should consider your self a test jumper.

Well since I have basically brought Vectran and Technora mediums to market, have developed line trims/line sets in the last 25 years or so for various canopies that are in use today, and lastly have test jumped them all; that is not problem.

Also of note,NZ Aerosports uses exactly the lines that I have had developed over the years as do a couple of other manufacturers.


MEL

Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

[gowlerk 1,904]

It's a little misleading to blame those incidents on the Spectra lines. Until recently almost all canopies of those classes were factory lined with Spectra, and they are among the most popular and common canopies ever produced.

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[gowlerk 1,904]

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Obviously you have never jumped a canopy with Spectra, lined that same canopy with Vectran and then jumped it.
I have and the difference is what I have previously explained.

That is strictly anecdotal and subject to your own prejudices and perceptions. Not terribly meaningful as data.

In any case, a distinction needs to be made between hard openings which may be a habit certain canopies and certain lines may have a problem with, and the type of rouge openings that result in serious injuries. Something else is going on with those. And as far as I can see it must have a cause rooted in the failure of the slider to stay in place long enough to control the spreading of the bottom skin. When that happens a minor characteristic of the lines is not going to be enough prevent injury.

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[masterrigger1 2]

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hat is strictly anecdotal and subject to your own prejudices and perceptions. Not terribly meaningful as data.

All facts are anecdotal to people whom perceive it as such.Data is data no matter how it is achieved.

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In any case, a distinction needs to be made between hard openings which may be a habit certain canopies and certain lines may have a problem with,

The distinction is that Spectra lined canopies are the problem. It is the common denominator.

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When that happens a minor characteristic of the lines is not going to be enough prevent injury.

Hard openings is always a series of events. Bad canopy design, bad line type choice, bad packing, etc...
If you eliminate one,better things happen less.

MEL

Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

[gowlerk 1,904]

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Hard openings is always a series of events. Bad canopy design, bad line type choice, bad packing, etc...
If you eliminate one,better things happen less.

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The distinction is that Spectra lined canopies are the problem. It is the common denominator.

If I read what you are saying correctly, you believe that only Spectra lined canopies are capable of giving jumpers catastrophic hard openings. And that if only people would use your chosen line type they would be eliminated?

I've got a lot of respect for your experience and knowledge. But this seems a little like hyperbole. Have you actually investigated, or at least received reports of, all cases of devastatingly hard openings and linked all of them to Spectra lines?

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[gowlerk 1,904]

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Although I would not install Vectran on a Sabre I which is #4 on the hard opening canopy list.

Now, that makes me want to see the rest of your list. What other canopies are on the "hit" parade?

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[masterrigger1 2]

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If I read what you are saying correctly, you believe that only Spectra lined canopies are capable of giving jumpers catastrophic hard openings.

Negative.
I am saying that Spectra lined canopies will more likely have a catastrophic opening than the other line types. This is because it has less friction available to the slider grommets and it also goes out of trim. The other line mediums generate more resistance to the slider and they stay in trim.

I am also saying certain canopies should only have certain line types installed.
For instance, A Crossfire should never have Technora installed as it will greatly affect the opening. It would because to that the slider will hang up most of the time.

I have been investigating hard openings for 11 years...

MEL

Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

[masterrigger1 2]

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Now, that makes me want to see the rest of your list. What other canopies are on the "hit" parade?

Here are the top four in order based on real life incidents:
1. Sabre II (Early Versions)
2. Spectre
3. Triathlon
4. Sabre I

All Spectra lined canopies BTW...

MEL

Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

[gowlerk 1,904]

masterrigger1

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Now, that makes me want to see the rest of your list. What other canopies are on the "hit" parade?

Here are the top four in order based on real life incidents:
1. Sabre II (Early Versions)
2. Spectre
3. Triathlon
4. Sabre I


All Spectra lined canopies BTW...

MEL

Do you know what was changed between early and later versions of the Sabre 2 that make a difference?

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[gowlerk 1,904]

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I have been investigating hard openings for 11 years...

I have long had a suspicion that the 3" tape that sliders are outlined with may be a culprit. If both the front and rear of the slider have a 3" border fold under it could leave a much smaller hourglass shape to do the job.

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[flipwithit 0]

I appreciate all the feedback. Hard openings with a sabre aren't a concern to me. Long story short, never been an issue, even with small suits and slick jumps.

I guess where I'm at now, is technora just a fancy word for hma, a hma hybrid etc etc? Because it's sounding like technora vs vectran at this point.

[mxk 1]

masterrigger1

Here are the top four in order based on real life incidents:
1. Sabre II (Early Versions)
2. Spectre
3. Triathlon
4. Sabre I

MEL, I'm surprised to see Spectre on that list. I have Dacron lines on mine and picked it specifically for its opening characteristics. Is it just down to the line choice or are there design aspects as well that put it so high on your list?

[parachutist 1]

flipwithit

I appreciate all the feedback. Hard openings with a sabre aren't a concern to me. Long story short, never been an issue, even with small suits and slick jumps.

I guess where I'm at now, is technora just a fancy word for hma, a hma hybrid etc etc? Because it's sounding like technora vs vectran at this point.

MEL would have the details on that.

From my observations and experiences: they aren't the same. HMA looks like it's ready to fray when new, like a fuzzy sweater. Technora is solid and stays that way. Maybe the fibers are the same with the difference being all in the coating.