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Been poking around looking for info about the primary stow for lines. From what I gather on sub terminal/ low jumps it does little to nothing to help stop line dump. Looks like most don't even use it for slider down jumps.

Is there any reason not to single wrap it on a sub terminal jump? What about double wrap? It looks like Troll says double, while Apex (what I have) says single wrap

Should I single, double, or not at all? Does it really even matter?



Thanks.

The purpose of the primary stow is to prevent the bottom skin from expanding prior to line stretch, which (from my understanding that I'm sure people smarter than me will quickly correct) discourages the slider from descending and tension knots from occuring. So no primary stow will fail at accomplishing this effect. One stow might not be as secure as two stows, but if you do two stows, it's possible the rubberband will break in the pack tray (with you unaware). I usually feel like I can accomplish the desired effect with one stow (although I sometimes do two when I'm skydiving my Raven), so the answer to one or two is going to depend on the rubber band and the thickness of your line set. If it feels secure, then you should be fine, but if it feels very tight, it could possibly snap prematurely.

Thank you for the reply, but I am talking purely slider down here. So it sounds like it doesn't matter if I do it or not, but there's not harm in a single or double stow. Worse case with a double is it breaks and does nothing.

There was a recent thread about this.
If I recall correctly someone mentioned that if using the primary stow it should be tight, as loose can mean the rubber band holds on to the lines on the outside of the bight while the ones on the inside are released.
I double stow mine for all jumps.

The tension knot piece applies to slider down.

the primary stow is not just there for keeping the slider up and preventing line stows, this is very incomplete.

the main purpose of the primary stow is staging the deployment. that of course includes keeping the slider in place before lines are stretched, and did you ever think about why and how it is actually supposed to prevent linedumps?

the thing is, parachute openings need some staging, or the malfunction rate goes up.
in the early days of parachuting canopy first deployment was the thing (so the rounds that they had were not restricted from inflating while lines werent fully out, lines were stowed on the back of the jumper). with time and higher deployment speeds they found out that this isnt working that well anymore, so lines first deployment took over. this means that you have some opening staging device that keeps the canopy from inflating before lines are fully stretched. (diapers, sleeves, pods, etc). in general this works really nice.

ever wondered why we still see many malfunctions like lineovers and tension knots, although we spend a lot of time packing really really nice, while in skydiving the packing is quick and dirty in comparison and those malfunctions are rare? because they have a really good staging device, the pod.

the primary stow is our staging device, it doesnt work as well as the pod when it comes to enforcing staging of the deployment, but it has a way lower rate of hangups/locking, so theres no reason to not use it.


as already stated in comments above, the reason why atair recommends double wrapping is that it is just holding onto the lines as a bundle way better than a single stow, in which the inner lines can easier slip than the ones on the outside in contact with the rubber.
http://parachutistonline.com/...uble-wrap-stow-bands


as stated i do not see a reason to not do it.
i would bet money that it is lowering the malfunction rate in pretty much every scenario.
so i do them always, double stow, from ultra low shit to wingsuit....

damn that's a good post. Nice to see

Last 150 Sd jumps no stow- Cleaner openings. SU double everytime

Agree with the long post above. I use a small rubber band with a big bite of lines single wrapped. What exactly do you mean by "cleaner openings"? I've used a primary stow on every single slider down jump I've ever done, and never had anything I would categorize as anything but a "clean opening".

Thanks for filling in the gaps in my reasoning.


The article mentions that single stows became insufficient as linesets got skinnier and skinnier. Do you think the size of BASE linesets (particularly the beefy ones I have on my BlackJack) makes it reasonable to single stow on some canopies?

yes, of course, thinner lines are a skydiving thing. i posted it more because of the nice pictures and to show that in skydiving theres something kind of parallel to this discussion going on...

My head hurts. All that considered....

SD jumps on my Apex summit/Lobo....

Double wrap the stow every time then? That's what it sounds like.

It's up to you.
I have some jumps with double stow. About 90 with single stow. About 10 without any stow. A single stow makes sense to me and that what I go with.
Think about it and get some of your own data to work with (jumps).

Yes !

Should be just tight enough to not fall out, but not tight enough to brake during hiking. Everything and anything else is legit. Doesnt matter one, two, or three stows as long as it fits within the first sentence.

Everything in this post is in reference to slider down/off jumps:

Think about what the stow does. As was mentioned above, it stages the opening in several ways. First, it holds your lines together at their bottom skin attachment to allow your lines to feed out in an organized manner, thereby preventing line-dump (I know, debatable whether this is legitimate).

Second, your stow holds the bottom of your canopy together for a moment to allow the bottom skin and the nose to start inflating AFTER you reach line stretch. Third, the stow releases and your canopy finishes doing it's thing.

This, I believe, is the theoretical model of the affect of a primary stow on opening. The reality may be that your primary stow gets yanked out prematurely and have no effect on the staging of your opening, I don't think anyone has done a rigorous study of whether or not a primary stow does anything or not (someone please prove me wrong!). Even though I and many others have done jumps without any kind of primary stow, using one does make sense at least from a theoretical point of view.

Now imagine the differences in the amount of force it would take to pull a double stow with a large rubber band vs a single stow with a small rubber band. When you think about the force that is being applied to that stow when you reach full line stretch, any differences in resistance applied by either setup will be completely negligible. Remember, if you weigh 180 lbs, you are applying many multiples of 180 lbs to that rubber band by the time you reach line stretch. I guess my point here is that you shouldn't worry too much about reefing your canopy too much with minor variations in how you do your primary stow.

tl;dr version: At worst, using a primary stow is not a bad thing. Whether you use a single or double wrap probably doesn't make that much difference.

Anyway, I hope that made some sense and gives you something to think about.

Thanks for the info. Exactly what I was looking for. I will continue to double wrap the stow. Just wanted some reassurance after reading some contradictory stuff and seeing apex suggest single wrapping.

Predominantly a slider down jumper with a significant amount of jumps. I've double stowed every jump I've done.

Check out how easy it is to unstow a double stow. Your worries will be over. Unless you're doing specialized low jumps, don't over think a standard rubber band.

Toddshoe169
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850 jumps in 29 years.


Registered: Dec 3, 2007
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May 12, 2016, 8:01 AM
Post #45 of 47 (323 views)
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Re: [DaveO] Free stowing tail pocket (Slider Off) [In reply to] Quote | Reply
To use, or not to use, the single “primary” stow under the tail pocket...that is the question.

It has become a very personal thing. Some jumpers swear by it and others swear against it, as is evident in this thread. In the very early days of BASE tail pockets all of the lines were rubber band stowed. Yes, a full stow tail pocket. Then free stow tail pockets came along and having that one single stow made some feel better.

I’ve made a couple hundred jumps using the single stow. But since then I’ve made 4 times that many jumps without. I personally decided to stop using the primary stow on no slider jumps for a few reasons:

1- Any stow will not release all the lines at the same time. Any lines that are not in direct contact with the rubber band (the inner lines) will escape the stow first. The lines in direct contact will be released later. I didn’t like that.

2- With a single bridle attachment there is no counter force to the lines pulling the tail down. Try it. Open a pack job. Anchor the bridle and pull the container away from the canopy and see what happens. The primary stow will pull the tail down and distort the pack job. I didn’t like that. Now, try it again this time without the primary stow. Pick the one you like best.

I stopped using the primary stow on no slider jumps. Once the tail gate came along it was a better solution (in my mind). The gate is open or closed. All the lines are either trapped or freed at the same time. This was in contrast to point 1. The Multi provides the resistance that I believe is needed to eliminate point 2.

On a rare occasion (like when jumping a canopy with ZP) or when I really need one more reefing device to slow an opening down I might use the primary stow. But first I would much rather use several wraps of direct slider control (on slider up jumps).

For a no slider jump I believe the primary stow is not necessary, but a tail gate is.

For slider up- keeping the slider at the base of the stabilizer until line stretch is complete is very important. If you don’t direct stow the slider then the primary stow is the next best option to achieve that goal.

These are the observations that have impacted my packing decisions, but I understand and respect that other jumpers may prefer a different packing style. For this reason Apex BASE continues to put a primary stow on all of our canopies so the jumper can have the option if they believe it is of benefit to their style of packing

Edit: next time you pack put a single stow(large-small) and pull lines out. Put on a double. Feel the difference for yourself.

What are your thoughts on tube stows?
https://www.rockskymarket.com/...+stoes&results=7
They should be less likely to break inside the container.

Don't use those tube stows are too strong.

If you're worried about a primary stow breaking, just change out the rubber band every now and then. I really never even considered the primary stow breaking after packing it into the rig. Seems unlikely.

I go back and forth on slider-down/off primary stows. Something I've heard before is that it can also be a ~pivot point for the packjob as it is going to line stretch. That in addition to all the things Huck posted.

No stow, 1 wrap, 2 wrap...follow your heart and don't think about it.

*body position*

Definitely not. Out of 25 year s skydiving and almost 20 base jumping, standard rubber bands have never been a problem.

Forget about what you read higher up, Rubber bands don't break inside the container unless they were almost broken to begin with. And then still probably won't until line stretch.

Thanks all for the replies. I'm continuing with a double wrap and checking the band isn't worn out.

As with most things BASE related.... I'm more concerned about the "what not to do's" that I may not know more than knowing what to do. If that makes any sense.

To play devil's advocate a little bit about the "pivot point" theory, your canopy isn't getting to line stretch, pausing at the primary stow, and then spinning 90+ degrees. 95/100 twists I've seen reverse video of happen on the way to line stretch before the primary stow is loaded... usually as a result of pilot chute orbiting, though occasionally as a result of body positioning or high wind in short delays. Body position, in my opinion, tends to make these offheadings worse more often than being the initial cause...like a 45 becomes a 90 or 90 becomes a 180 as the canopy becomes loaded unevenly through the risers and seeks to one side or the other, kind of like sitting unevenly in a skydiving harness under a tiny canopy sniveling, though not exactly the same of course either. This could be a distorted perception of course, because I don't really jump with anyone who has bad body position often or severely enough to create severe offheadings. Really, I think the only "pivot point" is the point at which the lines stream out of the tailpocket, which you have whether the stow exists or not. In theory, two small tailpockets could be better if you're dead set on removing that pivot point, but timing them to hit line stretch evenly would be nearly impossible and could increase effects of body position, riser symmetry, or even packing on heading performance. I'm sure this idea has already been discussed and subsequently dismissed.

So, if you're gonna use a stow, I think the point is that it's taut to the lines, holding them securely, but not ridiculous. If you have a fat lineset like some blackjacks, then maybe that's one small rubber band, prestretched, single-wrapped. If you're like me, maybe you want to use a half-cut large rubber band double-wrapped. This way I feel good about it being tight, but it would break before hanging up too bad... or at least that's my theory. It's more gear maintenance, but I feel all warm and fuzzy about it. I use the stow slider up and down, I've tried multiple methods from no stow to tight stow to multi-wrap, and I think more important than your stow method is just good decision-making about your jumps. Stay safe whatever you decide OP.

Indeed.

http://www.basejumper.com/...20side%20of;#2987988

Hi..i am a new user here. As per my knowledge no primary stow will fail at accomplishing this effect. One stow might not be as secure as two stows, but if you do two stows, it's possible the rubberband will break in the pack tray. I usually feel like I can accomplish the desired effect with one stow, so the answer to one or two is going to depend on the rubber band and the thickness of your line set.