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Semi Stowless Bag Questions

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Have been reading some threads on stowless bags but none quite addressed some specific questions I was pondering clearly, so can I ask, re understanding the Semi Stowless Bag option (context is in terms of the option for one on a Vector 3 rig):

Q1 - What are the advantages of it? (is it just ease in packing? is it supposed to give a better / on-heading opening?)

Q2 - What are the disadvantages of it, in particular re safety, if there are any? (e.g. less margin for error in packing method? increased chance for line dump if the packing was a bit off?)

Q3 - Is there any industry consensus generally that it's a better method/option?


cheers
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I've had the UPT semi-stowless bag for this past season, and love it.

Advantages:
Definitely easier/faster to stow lines.
Promotes on-heading openings, reduces chances of line twists since unstowing lines does not cause bag to rock side to side like a standard bag does as the tension of the rubber bands on each side come undone.
And you don't need to replace as many stows.

Disadvantages:
Paying for a new bag.
Other than that, I don't know of any.

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I agree with klafollette...

About 250 jumps on mine and I love it. Even if just for the ability to pack a little faster (I only change the rubber bands when they start getting worn out, which is roughly every 50 jumps).

The UPT one is a simple design, once you do it once, it's a walk in the park.

It's essentially the same type of idea that your reserve freebag likely has (not talking about racers here). All of the lines are stowed in a pouch and 2 locking stows to keep the canopy in the bag... and those work, right?:P

"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
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What about extra line wear from all that extra friction with the flaps? What lines are you using on your canopies?

There was another thread started a while ago where a guy noticed more wear. He was supposed to post photos but never did.



I've got vectran lines, and only ~200 jumps on the canopy that's currently in there... I see far more wear on the bk-tog line than anywhere else on the lineset.
"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
I'm an asshole, and I approve this message

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http://www.youtube.com/watch?v=RDuijFUD-4U
&
Taken from a previous discussion on UPT's Semi stowless bag which I found very informative and helpful for those who want to know. I have jumped my Semi-stowless bag for 320 jumps now and love it.

"I first started jumping the semi-stowless bag from UPT prior to them going into production because the designer wanted his design to be field tested using mostly an everyday jumper with what he thought would be typical skydives and pack jobs.

I make 325-350 jumps each year. Roughly 1/3 are camera jumps filming tandems. The rest are belly jumps as 4 and 8 way training, competing, coaching and FS organizing at boogies and events.

I make use of packers for about 275-300 of my jumps (one of the reasons for the designer to give me a proto type of his bag).

I now have more than 700 jumps on the semi-stowless bags using Katana 120s and Velocity 103s.

I have zero jumps (that means none) on wingsuits. So my opinion is based on my personal experiences and my general knowledge of skydiving and deployment sequences.

I have nothing but good things to say about the semi-stowless bag. It is essentially set up the same as a reserve bag except it uses a flap with tuck tabs for figure eighting the lines instead of sliding them down into a pouch.

This allows the packer to see what the lines look like as they are being figure eighted. A good thing IMO.

As recommended by the designer I use large rubber bands for the two locking stows and double wrap them around no more than 1 1/2 inch of line bite (usually a bit smaller).

Some people will tell you double wrapping is not a good idea and may cause bag lock. This is a myth (assuming the use of large bands and the proper maintance of your pilot chute and kill line length).

I've been double wrapping large bands for more than a decade on all my stows (locking stows included) even before the semi-stowless bag).

I love the openings of the semi-stowless bag. I've had mostly very controlled on heading openings. Any off heading openings (90-120 degrees) usually happen on my pack jobs because I've been told I sometimes pack a bit hastily. Thank God for packers.

The bag does allow you to get to line stretch quicker and cleaner than a conventional bag. I like this because I believe that the majority of line twists start and are caused before the canopy comes out of the bag.

Most jumpers replace the rubber bands only when they break or are extremely close to breaking. How many times have you wrapped a band around a line bite thinking "come on don't break..... just hold for one more jump".

This means that our bands are generating varying levels of force on our line bites. Some hold better and longer than others due to better (newer) strength.

I believe the single wrapping of line bites sometimes allow the lines to deploy out of sequence allowing one or more lines to sneak out early and wrap around another line bite which can and has caused bag locks. And I believe too much line bite helps cause line twists and out of sequence line deployment which can also cause line twists and bag lock.

I've seen footage of quite a few opening sequences using high speed cameras. Which means you can slow the footage down by roughly 2/3 of a normal video camera slow motion. The footage is quite enlightening. I think most people would be shocked to see how much bag dance and out of sequence line deployment is actually going on above our heads.

Now, this doesn't mean that it happens all the time but it does happen pretty regularly. It also does not mean that it couldn't happen with the semi-stowless bag but the design is such, and testing has proven, that bag dance and out of sequence line deployment is dramatically reduced to almost nothing.

I like my lines to come out quickly and cleanly (like a reserve) so my canopy can hit the air with the greatest chance of an on heading deployment from the bag.

After that, it's a matter of how well you packed and placed the canopy in the bag, your body position during deployment and the design and wing loading of the canopy.

All of this can and almost certainly will be debated by those who are nay sayers. And I believe that healthy, sensible, civil debate is good and necessary for further development of ideas in our sport and gear. And I welcome the debate by those who have actually given some rational and original intillectual thought to this subject.

Of course this is just my humble opinion.
+
As I mentioned earlier, you do get to line stretch quicker but it does not cause faster or harder openings. The openings are controlled by the slider and the packing (and canopy design).

If a person gets a hard opening it's usually because the slider was not well controlled during the packing and bagging process. There can be other factors but it's almost always the slider.

The semi-stowless bag does not affect the hardness or softness of the openings. It only affects the speed to line stretch which I like. It also allows the lines to play out in a more orderly fashion.

We must remember, we only use rubber bands to keep the lines in place until they are needed and then to allow them to play out in a relatively orderly fashion in what is otherwise a fairly chaotic couple of seconds. But those bands can and do create other issues as I mentioned above.

The semi-stowless bag does exactly the same thing but simply allows the lines to play out more consistenly."

All credit goes to Sandy Grillet who has more than 7,500+ jumps and 35+yrs in the sport
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Just make sure you don't start reading any of those threads where people debate closing rubber bands size, configuration, line dumps and all sorts of weird events contributed to having bends wrapped once instead of twice. >:(

Because you see, here are only 2 bands. Line dump happens on just about every jump, and the sequence of bands letting go of your lines is nonexistent (except for 2 closing bands). So according to rubber band hoaxers this design is the closest thing to having a death wish, yet people (me included) report more consistent, more on-heading openings without slammers (even with my girly pull with wingsuit in full flight). :P

The bset thing about this bag is better openings. Easier packing is just a bonus really ;)

I understand the need for conformity. Without a concise set of rules to follow we would probably all have to resort to common sense. -David Thorne

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Hi pnuwin,

Quote

What about extra line wear from all that extra friction with the flaps?



IMO there are so many variables during any deployment that it would be nearly impossible to quantify the reduction ( if any ) that any type of modern design line stowage pouch causes to lines.

Where one guy/gal might get ~10% less jumps due to line wear on any one type of pouch the next guy/gal may experience no additional wear.

Now that is not to say that I cannot design a line pouch that will create a lot of wear, because I think I could. :)

YMMV,

JerryBaumchen

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I have heard a lot of positive feedback from people who use one. I found a couple clips from UPT and found them useful.
I've been trying to put the links up here but they keep getting messed up. Go to YouTube and type in, Semi Stowless deployment bag, and the clips will come up.

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With line wear, there's not only the issue of how much wear might come from a pouch, but how much wear one would otherwise get with rubber bands.

Maybe there isn't much, but recall how rubber bands on hip rings could quickly wear leg straps. Rubber bands for parachute deployment tend to rotate and flip to relieve tension from lines pulling out, so that may reduce some of the frictional wear. But without a closer study, I'm not sure that the wear would be non-existent.

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I now have about 30 jumps on my new Infinity semi stowless bag. All have been wingsuit flights. The openings have improved to being on heading. I switch between a variety of canopies depending on what type of canopy I want. The Infinity bag can hold several size canopies and can be used as a standard fully stowed d bag as well. I like that I have options as to how I can use the bag.
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What about the Advance magnetic D-bag? Does anyone have any experience with them. I have one waiting for me at home once I get off of this deployment with a new rig and canopy attached to it.



Send it to me, I'll try it out and let you know. :P
"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
I'm an asshole, and I approve this message

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Just make sure you don't start reading any of those threads where people debate closing rubber bands size, configuration, line dumps and all sorts of weird events contributed to having bends wrapped once instead of twice. >:(

Because you see, here are only 2 bands. Line dump happens on just about every jump, and the sequence of bands letting go of your lines is nonexistent (except for 2 closing bands). So according to rubber band hoaxers this design is the closest thing to having a death wish, yet people (me included) report more consistent, more on-heading openings without slammers (even with my girly pull with wingsuit in full flight). :P

The bset thing about this bag is better openings. Easier packing is just a bonus really ;)



Right on!

There's a lot of horseshit talked about linestows. Anyone who jumps a stowless bag must be a witch!

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airtec does state that their AAD's are NOT affected by magnets and many people who do have magnetic d-bags haven't reported anything that I know of

But there hasn't been a long term conclusive study on whether or not magnets would effect an AAD over the course of many years. So whether you'd like to take the risk or not is up to you.

.......back on topic to semi-stowless bags ;)

For info regarding lift ticket prices all around the world check out
http://www.jumpticketprices.com/dropzones.asp

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You're probably thinking of the Bill Booth PIA 2007 video where he was first introducing the magnetic riser covers and covering the topic of "if the magnets being beside tape based video would erase the bits" part.

Obviously it had no affect whatsoever and did NOT erase any data as confirmed by DSE as well. He also did mention that it did not affect anyone with a pacemaker either as an older guy put them on his chest.
For info regarding lift ticket prices all around the world check out
http://www.jumpticketprices.com/dropzones.asp

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You're probably thinking of the Bill Booth PIA 2007 video where he was first introducing the magnetic riser covers and covering the topic of "if the magnets being beside tape based video would erase the bits" part.

Obviously it had no affect whatsoever and did NOT erase any data as confirmed by DSE as well. He also did mention that it did not affect anyone with a pacemaker either as an older guy put them on his chest.



That's the one.

Thanks!

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I bought a UPT semi stowless bag last year for my V347 and have jumped the following canopies in it:

Katana 135-85 jumps. Massively improved my heading performance and reduced endcell closure due to the shortened linestretch time. Had one case of a tension knot (500 lb HMA) which I will hit on later...

Velocity 111-7 jumps. Excellent opening characteristics. Had a chop due to body position and trying to manipulate the canopy too much during the snivel... Not the D-bags fault.

Velocity 103-12 jumps. Great Openings.

Pilot 132- 3 Jumps. Great Openings.

Thoughts: I'm a believer in it. I had horrible openings on my Katana with a traditional bag prior to going to the SS Dbag. Some of this was learning to fly the canopy through the deployment (after downsizing from a Jedei 150). A lot of it was the bag. The traditional bag adds a lot of what I call "bobble variable" into the equation during the linestretch of the canopy. On modern, higher wingloaded canopies that are designed to open slow-this can lead to a lot of goofy heading characteristics.
On a semi unrelated note: The SS Dbag principle has been working for hundreds of thousands of Reserve and BASE deployments (A tail pocket on a BASE canopy does pretty much the same thing), it is a proven system.

Pros: Less opportunity for the canopy to wander off heading. Faster to stow the lines, (once you learn how). Simpler, cleaner line stretch. If you are trying to put a small canopy into a too big main container (like I currently do)-the SS Dbag adds some bulk. Line Dump will not happen if you stow the lines cleanly and secure the tuck tabs. You will have rapid line stretch, but you're pretty much safe from line dump.

Cons: You have to train anyone who may pack your rig how to do so... This may have been a contributing factor to the tension knots I had on my Katana as mentioned above. Small, Soft lines have to be "figure-8'ed" carefully while stowing the lines to avoid tension knots...
If you are trying to stuff a larger canopy into a small main container it adds bulk. It's expensive.

-Harry
"Sometimes you eat the bar,
and well-sometimes the bar eats you..."

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Line Dump will not happen if you stow the lines cleanly and secure the tuck tabs. You will have rapid line stretch, but you're pretty much safe from line dump.

-Harry



I'm unclear on this:
1) Isn't this evil "line dump" exactly what this bag does the moment the flap releases?
2) If not, and line dump is when the locking stows come loose first and the canopy beats the lines "out of the bag" - then how is this any better?
3) I thought #2 was bag strip.

Can you explain to the class more about this "line dump" concept related to the SS bag?

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I'm unclear on this:
1) Isn't this evil "line dump" exactly what this bag does the moment the flap releases?



The flap doesn't release on the UPT SS bag, the tucktabs are held taught with the canopy in the bag, so they release when the canopy comes out of the bag.
"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
I'm an asshole, and I approve this message

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