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erdnarob

Reserve Spectra Rip Cord

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No, I'm making fun of the image of some crazed tazmanian devil madly slashing everything in sight including the reserve cord.

The chances of your reserve handle coming out are slim. The chances of a canopy collision are slim. The chances of having your reserve handle come out and being involved in a canopy collision are extremely slim. Now, reserve handle, canopy collision and lines wrapped around near your reserve handle coupled with hook knifing the spectra? If you live you'd better buy some lottery tickets!

Taking the emotional argument out of the equation and using logic, science and probability, the metal cables aren't killing piles of skydivers every year. I don't believe switching to spectra will change this. They are, however easier and cheaper to manufacture. I believe they are easier to inspect than swagings.

So take your pick but let's be reasonable in trying to see if there is a safety issue in this product.

-Michael

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I have to thank everybody for participating to this thread. We don't have always to agree. But the best will always come out from the controversy and this forum allows us to do it. B|

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

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Sorry I almost forgot to answer you.
Most of the countries having civilian skydivers are relatively advanced technologically speaking. Then I guess they have a system of gear inspection more or less organized. But the problem doesn't come from the country only, it also comes from the skydiver attitude. We are doing a high risk sport then we have to behave accordingly and our best investment is to be knowledgeable about our equipment. I know many skydivers in advanced countries who almost doesn't care about what they have on their back when jumping. They prefer not seeing their rigger packing their reserve for instance, even once. Could you imagine a high sea sailor on a sailboat not knowing his boat and the rigging on it ?B|. Or the mountain climber not knowing his equipement ?
Thanks for the participant on this thread who mentioned that "telephone" type housings used for ripcords were made of stainless steel. I swear I have seen some brass at least on the endings.:$

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

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> The chances of your reserve handle coming out are slim.
... not to me ... my velcro is new and shit and my low profile finds his way out ... even on the exits. One might be tempted to say that the chances of having shitty Velcro on a new rig are low too but it happen to me.

> Taking the emotional argument out of the equation
Can I keep the imaginary argument that you've brought at least? The tazz devil? I like it.
I have an imaginary tazz devil too. He jumps out of a Cessna and snag his spectra coord in something sharp enough from the door frame. He's name is Snagallot, Sir Snagallot and he likes to chew on Cessna doors.

Which one has a bigger probability of snags Metal or Spectra? (this is not a rhetorical question, I have no idea, I haven't tested this and I hate using personal hunches)
Lock, Dock and Two Smoking Barrelrolls!

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Suppose that you were in a canopy collision (CRW, after opening or in the pattern). This is a plausible and unfortunately too common occurrence. You whip out your hook knife and start slashing lines wrapped around your body. Unbeknownst to you, your RC has been dislodged. And as fate would have it, the RC cable (whether spectra or metal) has wrapped around a line of the other guy's canopy.



We had a very good laugh at this at the DZ yesterday. If you're madly whipping your hookknife around you should be careful not to cut your reserve risers or legstraps too.

As Booth said 3". If you happen to slash your spectra reserve then with a steel one you would have probably hookknifed the cable and deployed the reserve into the mess anyway. Maybe once you're done your mad slashing your AAD could successfully deploy the reserve in this case. Unless of course you believe AADs are unsafe too.

-Michael



You completely missed the point.

Maybe you don't know this, but I work as an engineer that does hazard and risk assessments on systems that range from the mfg of the shuttle's SRBs to mid-air retrieval systems. Failure mode analysis is also part of this work.

A severed spectra reserve cable is a foreseeable failure mode that may lead to catastrophic consequences.
Whether the spectra cable is cut with a hook knife or abrasion from another line is immaterial.

Don't assume that an AAD or RSL w/ or w/o a Collins lanyard will activate the reserve.
There might not be enough altitude for the AAD to re-arm.
The main might not separate and render the RSL system ineffective.

.
.
Make It Happen
Parachute History
DiveMaker

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> The chances of your reserve handle coming out are slim.
... not to me ... my velcro is new and shit and my low profile finds his way out ... even on the exits. One might be tempted to say that the chances of having shitty Velcro on a new rig are low too but it happen to me.



If this is happening to you regularly then I would suggest it is a major safety problem and you need to correct it before jumping again. I've only got 300 and change but this has NEVER happened to me. I have NEVER had a canopy wrap and I've NEVER had to use my knife. I've NEVER personally seen a handle floating, never seen a wrap, and never seen anyone use a knife.

I know in this sport shit just happens but sometimes I think people stress about very unlikely events. Sir Snagsalot will probably never get a chance to slash his spectra ripcord. When the OP gets his spectra or mine come with my new rig then I will spend some time comparing it by jumping around as a fake floater...

[reply[
Which one has a bigger probability of snags Metal or Spectra? (this is not a rhetorical question, I have no idea, I haven't tested this and I hate using personal hunches)



I believe the metal since it will have no give whatsoever. In other words if it snags and is pulled 1" then your pin moved 1" - POP. The snagged spectra will first have to stretch the distance of the bungee section before it starts to directly apply the pressure on the pin.

-Michael - Sir NoSnagsalot.

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Spectra reserve cables scare me. I've seen reserve handles pulled in CRW wraps before (both metal and pillow). I've seen lines get broken multiple times in CRW wraps. I've seen tons of really nice scars too caused by lines in wraps. A spectra reserve cable could get sliced in a wrap. It is a possibility. I just don't see a need for the additional risk.
I mean if there was some major problem with the metal cables that was taking lives regularly but there isn't.

If people drag their rig when packing, that's wear and tear. If the line rubs against velcro in the reserve pocket, that's wear and tear. There are so many potential dangers with this it just scares me.

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> I mean if there was some major problem with the metal cables that was taking lives regularly but there isn't.
Are you saying that we're adding something "new" (and this is a key word) to an allready working system that interracts in a predictable manner within it's average usages without having any *need* for it?
Do we have any other inovations like this out there that are driven by other things than necessity?
Hmmm, out of curiosity ... what do you think is driven by other things than necessity on wings and dolphin containers?
Lock, Dock and Two Smoking Barrelrolls!

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> The chances of your reserve handle coming out are slim.
... not to me ... my velcro is new and shit and my low profile finds his way out ... even on the exits. One might be tempted to say that the chances of having shitty Velcro on a new rig are low too but it happen to me.



If this is happening to you regularly then I would suggest it is a major safety problem and you need to correct it before jumping again. I've only got 300 and change but this has NEVER happened to me. I have NEVER had a canopy wrap and I've NEVER had to use my knife. I've NEVER personally seen a handle floating, never seen a wrap, and never seen anyone use a knife.

I know in this sport shit just happens but sometimes I think people stress about very unlikely events. Sir Snagsalot will probably never get a chance to slash his spectra ripcord. When the OP gets his spectra or mine come with my new rig then I will spend some time comparing it by jumping around as a fake floater...

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Which one has a bigger probability of snags Metal or Spectra? (this is not a rhetorical question, I have no idea, I haven't tested this and I hate using personal hunches)



I believe the metal since it will have no give whatsoever. In other words if it snags and is pulled 1" then your pin moved 1" - POP. The snagged spectra will first have to stretch the distance of the bungee section before it starts to directly apply the pressure on the pin.

-Michael - Sir NoSnagsalot.



I agree that if d123 is having trouble keeping his reserve handle in the pocket, he has a problem that should be attended to with all haste.

d123 mentions the rig is new. Well, sometimes even brand new rigs have problems. Sad but true.

d123, please have someone who can determine the cause of your floating handle look at your rig. Then get it fixed.

A recurring floating handle is a disaster waiting to happen. Fool me once, shame on you, fool me twice, shame on me.

With regard to the snag danger being different between a metal ripcord and a spectra ripcord, I don't think I agree with you, hackish.

Once things get snagged, they don't usually just magically free themselves. Metal ripcords are supposed to have some free play too. You should see it as the cable extending inside the handle when everything is in place as it should be.

But metal or spectra, I don't think a snag is going to be better on one over the other.

Again I will say that I am not in any way defending the spectra ripcord. I do not think it is really ready for general use. There are too many unknowns. It might be ready for people like Andre (erdnarob) to be doing field trials, but he is far better able to regularly inspect it and evaluate its real performance of the new component than the run of the mill jumper is.

So, though Jan and I had a difference of opinion going here a little earlier in the thread, I tend to agree with her conclusion regarding the spectra ripcord - it could just be a bad idea altogether. But at the very least, it is something that needs field trials in the hands of people who can adequately assess the performance of a new component.

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Hi paul,

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I agree that if d123 is having trouble keeping his reserve handle in the pocket, he has a problem that should be attended to with all haste.



I agree completely. This is not something to get fixed 'whenever.'

I once had a new roll of hook Velcro in which the 'hooks' would just fall off of the backing. I only had to do the slightest handling of the material and the hooks would fall off. I chucked that roll into the garbage and have never had a similar occurrence since.

Sometimes things happen that we think never could happen. I am always amazed when it does.

JerryBaumchen

PS) IMO ONLY, I think the Spectra ripcord is a solution to a problem that does not exist.

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With regard to the snag danger being different between a metal ripcord and a spectra ripcord, I don't think I agree with you, hackish.



It's entirely guesswork on my part and I could definitely be wrong. The reason I think it would have less chance of snagging is this:

Suppose you had the metal handle floating on the metal cable. If it's at the end of the cable - against the swage then there is (little as Paul points out) give. Something snagging it momentarily, arm, leg whatever else can easy pop the pin.

With the extra play built into the spectra cable you can then have the metal handle extend an additional 3" or so before it starts moving the pin. Arm or leg it may allow the handle to pivot around the obstacle. May. It may not.

When my insurace finally gets around to settling my new rig will probably have a R/C cable so I'll have all winter to play with it...

-Michael

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With the spectra line being larks headed around the outside of the handle, dragging the rig while packing, or even just rubbing the front of the rig against anything will have the rip cord pinned between the handle and whatever the rig is rubbing or dragging against. While spectra is fairly robust, and slippery as well, over time this will lead to wear on the line and require replacement.

I have to imagine the cost of a new line would be very low, as there would be no need to replace the D handle, but aside from the cost, it's just another area the requires attention from the jumper on a regular basis. Many jumpers are very bad with regular maintenence.


Also, with the larks head just going around the top of the D handle, it appears free to slide from side to side, and on the harness side is the velcro that hold the handle in place. Velcro + spectra line = not good. It might be nice if it was held clear of the velcro in some way. Even a wrap of super tack through the cable hole in the handle. Does the handle even have a hole?


I also wonder if the spectra is more prone to damage during a reserve deployment, be it via skyhook or handle pull. I know metal cables can get kinked during an RSL deployment, but otherwise they are pretty resiliant.

Are these cords sized differently for different rigs, or does the internal bungee make 'one size fit all'? One size fits all would make it easy for riggers to stock one or two extra lines, and have them available for installation when one is damaged.

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I know metal cables can get kinked during an RSL deployment, but otherwise they are pretty resiliant.



Vector RSL is different, and the metal cable does not get kinked (the RSL ends with a reserve pin, unlike other rigs, where the RSL pulls the metal reserve cable at approx 90 degree angle). Therefore, it will not be a problem with a Spectra either.

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Are there any "infrastructure" changes that need to be made on a Vector when switching from a metal cable to the Spectra cable, or vice a versa? I have recently ordered a Vector and on the fence as to which cable to install. I am almost certain I will elect to have a metal cable installed however would like to have the option or the Spectra cable once it has been field tested a bit more.

thanks

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A Spectra ripcord is a direct replacement for a "steel cable" ripcord on any Vector with a LARGE diameter ripcord housing. No change is necessary to add the Spectra ripcord later. If you order with an RSL, you automatically get the large housing.

Remember, a Spectra main ripcord, going through the same housing, has been "tested" on thousands of Sigma systems for 8 years now. Because a main ripcord is used on every jump, this 8 years of use is equal to many, many, many times 8 years of use as a reserve ripcord, which is only used every 800 jumps or so. At that rate, it will take 6,400 years (8 x 800) before Spectra, used as a reserve ripcord used on an equal number of rigs, receives an equal number of uses. I hope you can wait that long.

Also, your RSL, as well as the loop that holds your reserve container closed, are made of Spectra, as well as, (possibly) your main and reserve connector links and suspension lines. If you don't trust Spectra, you've got a problem.

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If attributing incidents to some particular piece of equipment, it is only rational to attribute saves and successes too. Even in the early days these innovations save lives and it is a jumpers conscious choice to select the gear he jumps based on potential outcomes. Bill can be proud of his record of saves, and I'm sure even the skyhook's ballance sheet is positive.

But talk is cheap, back it up by jumping a rig without any of Bill's innovations.

I know of at least one person who had a hard reserve pull due to following her training which told her to punch out at 90 degrees with her handle, I was given the same training but understood immediately what had happened to her. If you don't really understand the mechanics (and many people don't) you can give yourself a very hard reserve pull and scare the crap out of yourself as this woman. It's one of those factors you can never fully account for in the statistics of no-pulls or low pulls.

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You completely missed the point.



Looking at the failure modes of the new system while ignoring known flaws with the old system seems to intentionally miss the point, but it's always easier to resist change and stick with the status quo than to lead. Pretending there is no risk associated with not adopting a change is a safe and popular fallacy.

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Also, your RSL, as well as the loop that holds your reserve container closed, are made of Spectra, as well as, (possibly) your main and reserve connector links and suspension lines. If you don't trust Spectra, you've got a problem.



There's at least one incident where worn softlinks put someone in a wheelchair. On the other hand there's another one where reserve Rapide's were not done up by the rigger....

Trust but verify.

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A Spectra ripcord is a direct replacement for a "steel cable" ripcord on any Vector with a LARGE diameter ripcord housing. No change is necessary to add the Spectra ripcord later. If you order with an RSL, you automatically get the large housing.

Remember, a Spectra main ripcord, going through the same housing, has been "tested" on thousands of Sigma systems for 8 years now. Because a main ripcord is used on every jump, this 8 years of use is equal to many, many, many times 8 years of use as a reserve ripcord, which is only used every 800 jumps or so. At that rate, it will take 6,400 years (8 x 800) before Spectra, used as a reserve ripcord used on an equal number of rigs, receives an equal number of uses. I hope you can wait that long.

Also, your RSL, as well as the loop that holds your reserve container closed, are made of Spectra, as well as, (possibly) your main and reserve connector links and suspension lines. If you don't trust Spectra, you've got a problem.



Hi Bill,

First, I want to thank you for being active on the dz.com community. Its great to be able to reach you directly here.

Would you explain the necessity for the large cable housing?

With no marine eye on the end of the Spectra ripcord, wouldn't it fit through the narrow housing?

Or is the large diameter housing of a superior quality to the narrow housing?

Pretty much my whole consideration about the system is the difficulty inspecting the inside of the cable housing. With a steel ripcord, that was not much of a consideration. If the housings that are used are somehow guaranteed not to need such inspection, then my concern is reduced to a negligible amount.

Do you think there would ever be a hope to retrofit existing gear, other than a Vector with the large housing, with a Spectra ripcord?

If not, why?

Thanks!

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A Spectra ripcord is a direct replacement for a "steel cable" ripcord on any Vector with a LARGE diameter ripcord housing. No change is necessary to add the Spectra ripcord later. If you order with an RSL, you automatically get the large housing.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I suspect it is a case of "why change something that works?"
LARGE diameter housings are mandatory with old-style steel ripcords (Vector) and work well with Spectra ripcords. Since there is a risk that a customer will lose their Spectra ripcord and replace it with a steel ripcord, the simple answer is to continue installing LARGE diameter housings.

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