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brettpobastad

Double stowing suspension lines

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Was it those double-wide Vector tandem bands they double stowed and didn't break? I could imagine that happening.



No, a normal large, rugger band.

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I couldn't imagine a three foot wide drouge not breaking a regular rubber band at terminal.



The drogue isn't 3-ft wide after you pull the drogue release ripcord anymore.

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I've also had several tandem instructors, including a Strong examiner, tell me I needed to double wrap the stows to keep from getting line dump.



Line dump is no big deal. I've had it on several tandem jumps and wouldn't have known if it wasn't for the video. Every reserve deployment with a free-bag is basically line dump. Bag strip on the other hand is bad. The good thing is that it is very easy to prevent because all thaqt has to happen to prevent it is the locking stows must remain in place until the lines are taut. Since the locking stows are close together, there is about the same weight of line between the stows as there is on the outside of the stows, so the weight is neutral and the lines don't want to 'fall' out of the stows. This is why bags with the narrower stows (same width as the locking stows) are the way to go.

Derek

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I've also had several tandem instructors, including a Strong examiner, tell me I needed to double wrap the stows to keep from getting line dump.



You're not going to get line dump if you use the proper stow band, stow your lines neat, stow them the same length a bit on the long side.

I don't care if Bill Booth, Ted Strong, Domina Jalbert, Elvis or the good Lord himself, down from the heavens, tells you to double stow....don't you listen to them.

DO NOT DOUBLE STOW!
"It's only arrogance if you can't back it up"

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"Line dump is no big deal. I've had it on several tandem jumps and wouldn't have known if it wasn't for the video. Every reserve deployment with a free-bag is basically line dump."

I disagree. Lines properly stowed in a free bag will deploy in an orderly manner until the two locking stows are released. They all have the same tension as they deploy from the freebag. Besides, you want the reserve to open fast.

Lines "dumped" out of rubber bands on a main deployment bag can occur out of sequence if there is not proper tension on each stow. This can either cause a hard opening or a possible malfunction.

Loose stows on the main are not a good idea. There should be a "snap" on each stow as the lines are stretched to insure the lines are straight and clean before the canopy is released from the bag.

If your stow is loose, double it. If it is tight, leave it alone. The pilot chute is much stronger than most people give it credit for.

IMNSHO

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Lines "dumped" out of rubber bands on a main deployment bag can occur out of sequence if there is not proper tension on each stow. This can either cause a hard opening or a possible malfunction.



If that were true, then the no-stow d-bags would be causing hard openings and malfunctions. They are not.

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Loose stows on the main are not a good idea. There should be a "snap" on each stow as the lines are stretched to insure the lines are straight and clean before the canopy is released from the bag.



Again, if that were true, then the no-stow bags would cause mals and they are not. Same thing for free-bags. Why did I not have mals or hard openings on those 3 tandems where the video showed line dump?

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If your stow is loose, double it.



Why? Just get the right sized rubber band. Again, as long as the locking stows hold untiul line stretch, the canopy will open normally. No-stow bags and free-bags have proven this over and over.

Derek

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DO NOT DOUBLE STOW!

Why?

I have been double stowing since my last malfunction...That was 1989 and I have not had one since. Hmmm? Maybe I am on to something. Hell, if it is really stretched out I might even (gasp) TRIPLE STOW!

What is the advantage of loose stows?

Rubber bands, even tube stows do not wear evenly. You can start out with a complete set of properly sized stow bands and after time they can be different lengths. I don't replace them until they break. If they are loose DOUBLE THEM!

I can think of advantages to having tight stows, I don't see any advantage to having them loose and sloppy.

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DO NOT DOUBLE STOW!

Why?



Because it causes line twists and bag locks. With double wrapped stows, the bag tilts to the side more as the stow releases, this can cause the bag to spin.

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I have been double stowing since my last malfunction...That was 1989 and I have not had one since. Hmmm? Maybe I am on to something. Hell, if it is really stretched out I might even (gasp) TRIPLE STOW!



Do whatever you want.

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What is the advantage of loose stows?



Not loose stows, correctly sized bands.

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Rubber bands, even tube stows do not wear evenly. You can start out with a complete set of properly sized stow bands and after time they can be different lengths. I don't replace them until they break. If they are loose DOUBLE THEM!



If they are loose, replace them, don't be lazy.

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I can think of advantages to having tight stows, I don't see any advantage to having them loose and sloppy.



Not loose and sloppy. There is a middle ground between double wrapping and "loose and sloppy".:o Neat and corretly sized, single wrapped stows, replaced as necessary. I used tube stows because they didn't break very often. The only reason to stow any lines besides the locking stows for for a more orderly deployment. You can safely pack with only stowing the locking stows:o

Again, if you needed tight, double wrapped stows, then no-stow bags and free-bags would cause malfunctions and hard openings. They don't. So much for that theory:S.

Derek

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"Because it causes line twists and bag locks. With double wrapped stows, the bag tilts to the side more as the stow releases, this can cause the bag to spin."

Hmmm? Never had a bag lock and I don't get line twists either. So much for that theory....

Do you really think a doubled rubber band is stronger than the pull force of a pilot chute?

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Do you really think a doubled rubber band is stronger than the pull force of a pilot chute?



Think? No, I know it is. I had a bag lock on a tandem with normal, large rubber bands. Just because it hasn't happend to you doesn't mean it doesn't happen.

Derek

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Yes the bag is my design. I made it several years ago and it is the only one I have or will make.

Sparky



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

Hee!
Hee!

Back in 1983 I bought a second-hand Eze-Flyer, (made by Ron Marshal at Roger Sport) and it had a reserve-style line stow pocket on its main d-bag.

Then in 1985 I bought a new Mirage from Skydive Gunter (West Germany) and insisted on a line stow pocket on the main d-bag.

I made hundreds of jumps with both d-bags and had hundreds of decent openings.

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I can think of advantages to having tight stows, I don't see any advantage to having them loose and sloppy



1. Double Stowing your suspension lines is not a good idea because it can contribute to line twists, off heading openings and harder openings.

2. Double (or triple or quadruple) stowing WILL NOT cause a bag lock.

These are the facts.

Brett
"It's only arrogance if you can't back it up"

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2. Double (or triple or quadruple) stowing WILL NOT cause a bag lock.



Not too long ago, I saw someone get bag lock on a sport rig from double stowing using stow lengths of about 3 inches. The pc appeared to be functioning properly because a few of the stows did release, but one locked up tight.

Between seeing that and hearing about what happen to Derek on that tandem rig, I'd say that it can happen. Maybe not often, but it can happen.

John

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Between seeing that and hearing about what happen to Derek on that tandem rig, I'd say that it can happen. Maybe not often, but it can happen.



First of all, I need to make the statement that, yes, anything can happen! We're trusting our life to a buncha nylon and rubber bands. And of course, I wasn't there to see the results of 'ol hook n release' bag lock tandem. So it's maybe not quite fair of me to say this but I will anyway. You didn't have a bag lock because of double stowing your lines. Hook n pile didn't have a bag lock because of double stowing his suspension lines. John, you seem to be onea those newer jumpers that is going about things in the right way. I personaly apreciate that. But be carefull who and what you listen to.

If you've seen the movie Spinal Tap, you'll get this analogy....just make ten louder!

Brett

PS Check out the attached picture. Might Hoop n Load's bag lock have locked something like this?
"It's only arrogance if you can't back it up"

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That 'bad stow' pic is definitely bad, but I don't think it would cause a bag lock.
People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

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Might Hoop n Load's bag lock have locked something like this?



No, pobastard, it wasn't. When I looked over my shoulder, the lines were even, running to one stow, which would not release. On the ground, I pulled all the lines as they went to 1 stow, holding the bridle with my foot. They would not release.

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Hook n pile didn't have a bag lock because of double stowing his suspension lines.



You right, it wasn't because I double wrapped them, the packer did. The bag lock was caused by double wrapped stows.

Derek

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OK - I think we all know who is for and against double-stowing.

Since the incident in question happened on a Tandem Vector, here is what Relative Workshop says about line dump and double stowing tandem bands:

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Proper Stow Band Set-up

During test and evaluation jumps that RWS has done during the past several years, we have confirmed that our current recommendations are still valid. By using a large Tube Stoe on each of the two center locking stows on your main bag, and wide RWS tandem bands in all other locations, you will get the most reliable deployments possible. In combination with line bites that are 3.5-5 inches long, you can albeit eliminate line-dump. According to John LeBlanc from Performance Designs, line-dump is the primary cause of line-overs, tension knot malfunctions and hard openings capable of damaging other important components such as main risers, canopy and lines. Large Tube Stoes are available through RWS or Sky Systems, the manufacturer of Tube Stoes.

How to Prevent Bag Lock

There are several causes of 'Bag Lock.' The primary one being the type of stow band and how it is used. See our note in this newsletter about 'Proper Stow Band Set-up.' Military tandem instructors are taught to double-stow our wide tandem bands because they jump with heavier weight (up to 1000 lbs.) and use larger drogues with diameters of 60-72'. Double-stowing in the sport world with 54' drogues will most likely yield a bag-lock. Another cause to consider would be extra stow bands left on the bag which are not being used. These bands can jam up a line bight quickly. If nothing else, they can certainly cause a tension knot malfunction.



(Bear in mind that the line stow length on a tandem is longer than a sport rig because of the bulk of the stows.)

I have a lot of jumps on the military tandem rigs referred to in the second paragraph that double-stow the rubber bands (the first two locking stows are single-wrapped tandem tube stoes). The canopy is a PD421 loaded as heavily as 1.54:1. On loads that heavy we use a 72" drogue. I would not put one of those rigs on my back that had single wrapped line stows, nor would I allow anyone else to do so.

The Sigma Tandems we use at Raeford (Sigma 370 canopies) are single-wrapped tandem bands all the way across the bag. We use a standard 54" drogue and load the canopy as high as 1.35:1.

On both my personal canopy and my work canopy (both with 825 lb microline) I use standard rubber bands on the locking stows, double-wrapped, and mini rubber bands on the regular stows, single-wrapped. I have consistently smooth openings on heading, with my work canopy (a Silhouette) occasionally diving 90 degrees to one side.

In all four scenarios mentioned above, I have never had as much as a hesitation let alone a bag lock.

In Derek's situation I firmly believe the double-wrapped tandem bands caused his bag lock malfunction. Why? Because I trust the manufacturer's guidance.

I also believe that whatever stow band you choose should hold the line tight enough in place to result in 8-12 pounds of force to release each stow. Why? Because I trust the manufacturer's guidance (see this article).

Brett: you posted this question because you were "curious as to jumpers and riggers opinions" (your words). You received several very clear opinions from some highly experienced Riggers whose knowledge is respected both in these forums and elsewhere. Then you chose simply to argue, with the objectivity of your replies eroding to silly name calling and boldly stating that people reading this post should listen to you instead of three pioneers in the sport, a dead rock star, and God. We all understand what your opinion is.

Everyone else: information posted in this forum can be very informative and has likely saved people from injury or death. The key is in making an informed decision based on gathering information from trusted sources. Do your homework, discuss all of the information with the manufacturers of your equipment and experienced professionals that you trust, then decide for yourself.

This thread will continue if the posts are objective and civilized. If replies are made simply to make the other person wrong or to discredit them somehow by perverting their username, it will get locked.

Nuff said. [:/]
Arrive Safely

John

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This thread will continue if the posts are objective and civilized. If replies are made simply to make the other person wrong or to discredit them somehow by perverting their username, it will get locked.



I'm done, John. People certainly know where I stand on this issue. The smart ones also realize I'm correct.

Brett
"It's only arrogance if you can't back it up"

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the smart ones realize quite the opposite



Well said, Marc. I think I'll stick with Bill Booth's thoughts on the matter as I tend to think he knows what he's talking about.;)
Sky, Muff Bro, Rodriguez Bro, and
Bastion of Purity and Innocence!™

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thanks, brett. this has been one of the most entertaining threads in a long time.

I feel, for sport rigs, there is nothing wrong with double stowing lines. the locking stows don't usually need to be double stowed, and I don't feel good about double stowing them, but I have done it many times without any issues. and for the rest of the stows, well, I haven't used small rubber bands since mid 2000.

for those that don't know me, I have about 5-6 years packing experience, so I am not just relating what has worked for me, but for hundreds of my customers over the years. I don't pack tandems, and probably have less than 1000 pack jobs on student rigs.

then again, this is just my opinion based on years of packing at busy dz's.
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Abbie drove me to Idaho and all I got was this lousy sigline

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