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anybody using a tube stow for primary on slider up terminal ?

no, we just use rubber bands

I prefer rubber-less myself.

explain please.
Take care,
space

Tube stows are loops of surgical tubing made for stowing lines on skydiving dbags.
I use rubber bands and double wrap about a 6" bight. It's just that every once and awhile on tracking jumps only I get a real hard opening and was thinking a tube stow might provide a bit more tension and was wondering if anyone out there was using them.

thank you for the explanation of what a tube stow is :)

The purpose of the primary stow (aka the hidden/secret stow) is for indirect slider control - to facilitate slider staying up all the way until complete line stretch. By the time your primary stow gets loaded you are at near complete line stretch, with the nose exposed and taught against the relative wind, and thus canopy a moment before inflation/expansion.

My guess is that your PC size and slider type will make a shitload more difference than choice of rubberband under the tail pocket. The only thing I can think of is if you wrap the bite of lines too tight you may get slight line dump (the whole 12" worth :) which may feel like(ish) a hard opening.

I'll let someone with a bit more knowledge answer this one ...

Not only. In addition to slider control, primary stow helps keep packjob tight during extraction (which prevents premature partial inflation and reduces chances of hard opening and lineover) and helps equally preload the lines just moments before the full linestretch (which improves heading performance and reduces changes of tension knots) as the coils of lines can be extracted unevenly from the tailpocket.

I think primary stow is No.1 factor that makes BASE openings so reliable.

The primary purpose of the locking stow is to stage the canopy inflation. It keeps the canopy in a tight bundle until it reaches line stretch. If you remove the locking stow, two things can happen.

First, you can see the slider deploying down slack lines, which can cause lots of problems (such as tension knots). This can be avoided by using the direct control stow to take a bight of the slider fabric.

Second, you will see the slack lines moving past each other as the parachute begins to expand (prior to reaching line stretch). Slack lines moving past each other is also a contributor to tension knots.

Personally, I use both the locking stow (indirect slider control) and the direct control stow on every slider up pack job. I mostly do this in case one of those rubber bands breaks prematurely (i.e. while the rig is being moved around prior to the jump).

I have tube stows on a couple of my canopies at the locking stow position and have had no issues with using them.

I originally put them on because the locking stow band broke when I had run out of large rubber bands (it was at Bridge Day, if memory serves) and the first person I found who could give me a substitute had tube stows rather than rubber bands. I then left the tube stows in place because I'm basically a lazy person and couldn't be bothered to switch them out for a large rubber band once I got home.

Drop your knees and sit up a little on openning. That way your body won't be whipped through as big of a rotation. I bet you aren't getting hard opennings just whip lash. Leave your pack job as it is.

I don't use a locking stow of any kind. I have at least 100 slider off jumps without one and a few (10 maybe) slider up terminal wingsuit jumps without one. No problems. yet...

I don't use a locking stow of any kind.

Can you sell us on the benefit(s)?

I am genuinely curious about this.

Slider up it is imperitive with the canopies I´ve jumped. Also with others that I´ve witnessed out of 8000 SU jumps.
Extremely uncontrolled line/neck breaking (read as knocked unconscious) hard openings without.
Take care,
space

I only have 252 BASE jumps
but have used it every time.

I still wonder why someone
would NOT choose to use it.

Here is the first time I asked:
http://www.basejumper.com/...post=2916956#2916956

I was bloody curious to know the same. Had been watching on this thread for this very answer.

Thanks for the link to the other thread you had started. That was a good read. Thankfully did not end up getting me confused reading different opinions/practices.

As I learned/understood, the locking of the lines made PERFECT sense. For BOTH SD and SU. And never once when packing ,for both SD and SU I thought in the contrary. But seeing Greeny making some changes to this 'general' practice(that seemed logically correct though), made me think. Seems like there are things to learn and see how they come out by ourselves. May be only at Perrine I would say. I personally wouldn't go without a lock but would certainly want to see how it goes without on a jump like at Perrine. For me, the primary concern would be of tension knots. Without the lock, even if you stow the bite into the pocket (tighter for Dagger as I experienced) without a rubber band. I would think the 'loose' lines are more prone to get tension knots than otherwise.

anyway...reading different posts I can only say (as someone put it quite aptly)

Personal preference - as with most things in BASE.

I know my personal preference ...LOCK THE [FUCKING LINES.

Was actually going to ask that in a separate/new thread as it seemed logical to do to reduce the 'hard' opening when I was thinking how to reduce the 'wear' of ones back during sub-terminal and terminal jumps. Thanks for confirming my expectation.

To have any really relevant data, you'd need to go without for a couple thousand jumps. Even without the locking stow, the chance of a tension knot is very small--it's just the consequences that can be huge.


Don't be fooled into thinking "well, it worked 15 times off the Perrine, so it must be a good idea..."

I had a friend who thought that since he was getting on headings from his TARDovers for a month here, he could easily do one off a cliff in Moab. Turned out that was not such a good idea.

yes, the consequence can be huge, indeed

You know, as we were talking about the size and location of the locking stow in another thread, I was actually going to come up with this question -- "Tension knots in a more spacious pocket".

As your experience tells, the possibility of tension knots, (considering only the case of unlocked but stowed bite) is quite small. I had a doubt about the difference in size of the tailgate pocket itself. Since the figure-8s have more room to move around in a spacious pocket as against that of smaller like Dagger (that also has a tighter locking pocket/hole) , would it have more chances of tension knots?

to present my doubt in simple words, I am getting a feeling that

"spacious pocket is more prone to tension knots while
tighter pocket is less prone to tension knots."

am certainly not passing a statement here, just curious if what I think is even logically right if not practically an eventuality.

Thanks for that reminder! I am trying hard,and somewhat successful, to keep that in my head these days.

1st off. I live in Moab and I jump regularly without a locking stow slider off. I still enjoy the (perceived) comfort of a locking stow on Slider Up jumps but have been experimenting with and without on wingsuit jumps and I have yet to notice any difference at all. (but don't have enough to be fully convinced, my main concern is tension knots but with a neat controlled packjob and lines in good condition it shouldnt be an issue)

As for the benefits: There are no discernible benefits per say other than one less packing step. A good friend/rigger who has been jumping forever and used to work for gear manufacturers in the 90's as well as the owner of a certain major gear manufacturer now have convinced me that the locking stow does absolutely nothing for openings and is completely useless. It took me a bitof time to believe them but once I started jumping without I see no reason to go back to using it. Why make anything in BASE more complicated than it needs to be if there is no real benefit? Simple logic.

I'm curious how the slider is kept up at the stops when the parachute is yanked out of the container.

Seems like not using a primary stow is a very inappropriate configuration for slider up jumps.

Probably!

Direct control or slider gate will that for you. I am all for it and use one, but just answering your question.

It's just the tail pocket. The tailgate is a totally separate piece of gear. Don't confuse them.



That's another issue where manufacturers have varying solutions.

The thought process basically goes:

A tighter, smaller tailpocket will hold the lines in place better, hence be less prone to tension knots. However, a smaller, tighter pocket will also be harder to neatly close the lines into, hence more prone to tension knots.

A larger, looser tailpocket will be easier to close the lines into neatly, hence less prone to tension knots. However, a larger, looser tailpocket will not hold the lines in place well, and hence be more prone to tension knots.

Obviously, there is a balance to be struck somewhere there. The tailpocket size has to be balanced to the bulk of the lines (a design decision) and to the jumper's packing skill (a gear selection decision).

The range runs from canopies like the Rock Dragon (super tight pocket) and Dagger (tight pocket) designed by Vertigo, to the Troll (Atair), Mojo (Consolidated Rigging), Ace and Blackjack (Consolidated Rigging) with mid-range pockets, and up through the FOX and Flik (Basic Research) with loose pockets.

Yes I understand that, but the direct control releases quite easily. It mostly depends on the primary stow to keep the lines together during canopy extraction and line extension. It will absolutely work some of the time. I doubt that it will work much of the time.

Am corrected. Not confused with them physically of course but correct terms very important when asking questions :)

Haven't seen a Rock Dragon yet but the tailpocket tighter??!! I thought Dagger's was a super tight already :-D

I see the points that influence the decision in the pocket size. Good read !!

Thanks.

It seems that way to me, too, but I know some very technical minded and respected jumpers who would take off the locking stow for very low slider deployments, because they felt it could cause a split second slider snivel.

Like I said, I'm with you on this one, but I've seen the other side, too.

I always thought a tapered pocket would make a lot of sense seeing as most people taper the stows.

Last time I talked with Todd from Apex he was experimenting with a velcro-less tapered tail pocket. I played around with it a bit and it seemed to work pretty well.

Dammit - I'd better withdraw my patent application ;)
Velcroless eh? Would that be a magnetic tapered tailpocket then?

Nope, no velcro, no magnets, no nothing.

It works more like a "line funnel". I played with the demo set up quite a bit and I could never get the lines to snag; even if I just piled them in there.

You should be able to build a tail pocket with just tuck flaps (or even with no moving parts, if you make packing it a bit harder).

Another idea I've always like is putting stiffeners in between each loop of line to separate them.



Have you tried that with a regular tailpocket? When I teach I sometimes have students who are stressed out about the lines feeding from the pocket. I do a demonstration where I stuff all the lines in as fast and messy as I can and then pull them out. They haven't snagged yet. I wouldn't recommend packing that way for a jump, but it's an interesting thing to play with to put your mind at ease if you're not used to tailpockets.

There was a time before tail pockets,primary stows and tailgates SD & SU . Lines just in a fig of 8 or coiled in the pack tray. Never had and never saw anyone else have a problem with it. Not saying anyone should take a step back into the Dark Ages though

When I towed banners we would store the towrope in a 5 gallon bucket. You would put it in the bucket in a rapid hand over hand move just randomly throwing it in as fast as possible. It would ALWAYS come back out without a tangle. If you coiled it in neatly, it would ALWAYS tangle on the way out.

Counterintuitive.

Like this in the attachment?
Take care,
space

Yes.

Is that something you made yourself?

OK. I think this has already been taken care of when making that thing by the choice of fabric used, but just to kill my curiosity.....wouldn't that add some weight to the tail? I have a feeling, the little extra weight is really not going to matter much to the inflation characteristics but still asking.

that's actually looking simpler and neat (if done well of course )

I will see if I can sort it out for you. Rocket Man Peter designed it and Hans Ostermüncher built it.
I do have concern about the added weight.
take care,
space

What does Hans munch?