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Skydive_Gregor

Dangerous stowless bag from Seamless Rigging !!!

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mjosparky

500 jumps on a trash pack. This is where you pull all the lines taught, rap the tail around the canopy and put it in the container. No bag or stows. Never had a hard opening.



A good point to make. After all, terminal BASE jumps work too.
But we're talking F-111 style material in those cases. Probably not good to freepack (or BASE pack with a tail pocket) a modern higher performance canopy where slider placement and size tends to be crucial.

(Did you restrain your slider with an elastic or leave it free?)

And it does seem to be a premature, as the OP stated. I don't see evidence of a super quick pilot chute pull, in the moments his right hand was mostly out of view on the video.

To combine what others have basically said, although
a) the bag didn't cause the premature, and
b) the slider happened to stay up until at least the very beginning of line stretch (but soon went on an angle and did not allow for a controlled, well staged opening)
... a bag that fails to contain lines and parachute at a sitfly speed is still probably considered a bad thing.

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Hi Gregor,
glad you are alive .. That could have gone bad ...

My thoughts on that whole stuff:
1st: you had a premature opening at a higher freefallrate
2nd: you had an out-of-sequence opening

to 1st: that happened before, will happen again and is not a joke
even if you jump alone, blablabla ..
> you know the hazards in a situation like this.

How to prevent that?
Gearmaintenance (pouch, length of closing loop, ...), proper packing (stowing the bridle, hackey,..) and
checking your handles before you exit is worth thinking about.
If you drive a faster car at higher speeds, you need more concentration ...

to 2nd: if you have an out-of-sequence opening, that may get worse. linedump etc. is not funny. Seeing the lines at you after the container was open is frightening. Especially at 0:29 ..
if the bag only works on lower speeds, that has to be checked.

See https://www.youtube.com/watch?v=2vRe51Ap0dI
as an example.
At 0:47 you see a premature opening , but with a staged sequence.
Your bag should at least provide linestretch before the canopy falls out of the bag ..

that demo in your clip with the shake of the bag is very interesting ..

Summary:
you have to judge if any stowless-bag is able to guarantee that in-sequence opening, even at higher deployment speeds.
Even that, prematures can cause damage to material and persons, no matter which gear was used...
--------------------------------------------------

With sufficient thrust,
pigs just fly well

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First of all, I wouldn't jump that bag design. Many gear makers and riggers have decided that magnet closure on main deployment bags isn't a great design in the current configurations we see...as you now realize.

Second, pulling right out of a sit is kind of irresponsible. Give yourself the best opportunity to survive when it's within your control...

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Amusing how that UPT interview combined two sales pitches about a new d-bag design and a new removeable deployment system.

How long before we combine both functions in a RDS?
Hah!
Hah!
...... similar to the deployment system on PZ-81, Rogallo reserve (made in Russia). PZ-81 bridle links the reserve pilot-chute directly to the slider, preventing premature descent of the slider.
Some American-made, military HALO and HAHO containers use similar bridles and they were popular with some Jalbert Para-Foil jumpers circa 1980. Double-length bridles doubled the reefing force of a single pilot-chute. One end of bridle was tied to the pilotchute, while the other end was tied to the middle of the bottom skin. The bridle ran through a pulley sewn to the middle of the slider.

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Hajo

Hi Gregor,
glad you are alive .. That could have gone bad ...

My thoughts on that whole stuff:
1st: you had a premature opening at a higher freefallrate
2nd: you had an out-of-sequence opening

to 1st: that happened before, will happen again and is not a joke
even if you jump alone, blablabla ..
> you know the hazards in a situation like this.

How to prevent that?
Gearmaintenance (pouch, length of closing loop, ...), proper packing (stowing the bridle, hackey,..) and
checking your handles before you exit is worth thinking about.
If you drive a faster car at higher speeds, you need more concentration ...

to 2nd: if you have an out-of-sequence opening, that may get worse. linedump etc. is not funny. Seeing the lines at you after the container was open is frightening. Especially at 0:29 ..
if the bag only works on lower speeds, that has to be checked.

See https://www.youtube.com/watch?v=2vRe51Ap0dI
as an example.
At 0:47 you see a premature opening , but with a staged sequence.
Your bag should at least provide linestretch before the canopy falls out of the bag ..

that demo in your clip with the shake of the bag is very interesting ..

Summary:
you have to judge if any stowless-bag is able to guarantee that in-sequence opening, even at higher deployment speeds.
Even that, prematures can cause damage to material and persons, no matter which gear was used...



You have got right Hajo. Thanks for your reply.

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pms07

First of all, I wouldn't jump that bag design. Many gear makers and riggers have decided that magnet closure on main deployment bags isn't a great design in the current configurations we see...as you now realize.

Second, pulling right out of a sit is kind of irresponsible. Give yourself the best opportunity to survive when it's within your control...




"Second, pulling right out of a sit is kind of irresponsible." - I don't know if I good understood - I don't open by myself.


Quote

Would you tell us how the decision to use this bag was made?

Did someone you respect suggest it?

Or was this choice made all on your own?



That was my own decision. Bad decision.

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Skydive_Gregor

***I'm not sure you can blame the premature deployment on your d-bag. Might want to look into your BOC/bridle protection/closing loop area first.



I don't blame premature opening on d-bag.
I blame d-bag (magnets) that it didn't keep canopy inside bag when PC take it from container.

if the process of opening were normal, links would be tightened and there would be a normal process of opening a parachute.

It didn't happen and all lines and canopy were on my back and legs, canopy just blow up, slider does not slow down the opening.

BOC/bridle protection/closing loop - everything was ok, checked on the ground by me and my friend, before exit i have checked hackey. BOC is in very good condition (DOM 07.2015).

Your main problem was the premature, which put your canopy in the air while you were in a freefall speed that is greater than optimum. That has hurt and killed people who have had normal d-bags. Deployment at high airspeeds is a known and well documented danger to both you and your equipment.

Your slider was still at the top when you reached line stretch and so was still doing its job, but in the higher airspeed the canopy inflation was so violent it forced the slider down much faster resulting in far higher decelration forces. This also has nothing to do with the out of sequence cause by the dbag and it all would have happened even if you had a normal dbag.

Your secondary problem was an out of sequence deployment. This can cause tension knots, line overs and asymetrical inflation resulting in line twists. If none of these happened then the dbag did not cause any of your issues. I would still change the dbag though.

Happy to be corrected by more knowledgeable people (and there are many :)).
Rich M

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I hate that stowless bags are a thing. It's a perfect example of skydivers choosing cool over what works... :S

From the video the only question I can see is if the stowless bag is more likely to result in an out of sequence deployment / bag strip. At freefly speeds with weak magnets I can definitely believe it.

That said, at freefly speeds it's possible that it might have happened with a traditional D-bag as well. There's just no way to tell.

The premature deployment and everything that happens after line stretch is immaterial to the D-bag discussion.

You got REALLY lucky none of those lines wrapped you. Figuring out why you had a premature deployment is the first thing to do, because it's either poor maintenance, poor packing or not checking your shit before exiting. All of those are easy fixes and are only on you.
Break that link in the chain and nothing else happens...

Don't fix what ain't broke.

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There is a whole community of skydivers that jump magnetic bags. There are manufacturers in the USA and in Belgium. These bags have been around for close to a decade! Each manufacturer has sold, in this lapse of time, a few hundreds of their goods. Probably thousands have been in use for 8/10 years. Any idea how many jumps have been made with these by now..? People chose these D bags because they're 'cool' over safe...??? Maybe, just maybe some people were simply seduced by the idea of not having to deal with rubber bands any more. Maybe the wear on the lines created by the friction of each band at opening was taken into account too. Maybe the disappearance of the rotations of the bag at each stow released during deployment was appreciated... Maybe , the fact that tens of thousands of jumps made in a decade with these magnetic bags without any reports of proven malfunction directly linked the bags themselves has had people think they might be safe to use... But I may be wrong. I have magnetic bags and always say exactly what the person who got one before me said to me when i was considering trying one: 'I will NEVER go back to rubber bands, and my only regret is having waited so long to try one'.

--------------------------------------------------
The tongue is NOT only a tool for speech!

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frenchcloud

Probably thousands have been in use for 8/10 years. [....]Maybe , the fact that tens of thousands of jumps made in a decade with these magnetic bags without any reports of proven malfunction



You are talking about FULL magnetic bags, with no elastics or tabs, at all, so that the bag closure is also done with magnets?
Are they really that popular? And you have ones that work well?

But if you are talking about bags using magnets for line stows only, that's nice but not relevant here. (I made one myself over a decade ago, and agree, they are nice.)

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Have to admit I really like my fully magnetic bag. I tried the same thing as the video but I fully closed it before trying to shake it out and it would not come out. Additionally, Brad provides great customer service.
My goal is that when all is said done I will have a big pile of well used gear and a collection of great stories.

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I have some rigs for rent in my school, there are different manufacturers, different D-bags. I have two lazy bags, but any stowless.
Dear skydivers, could you explain your choice? Why full magnets? Is it complicated to replace some rubbers sometimes?

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My theory is no one wants to buy rubber bands. My dzo gives them away so no issue. I pack all types for many people and prefer standard d bags with rubber bands and 4 locking stows (vector?) seems more secure (safer) to me. on my racer all 8 stows are locking stows, I believe no way the bag will be stripped off the canopy...

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:( Don't use a stowless bag! I was around when the original ram-air reserves were introduced. Bag strip was real then and sure is now. I recommend you find a four stow deployment bag for your main. As you demonstrated, the inertia of the canopy and lines can leave it in the container at high deployment airspeeds. While we used the pouch on the original free bags, the stows evolved to bungee or "O" rings. Only really good rubber bands should be used to stow suspension lines. Longer bights are preferred over small ones.

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RMURRAY, It is simple answer. I agree. I also can noticed that skydivers are more, and more stupid. Spending fortunes for tickets, fortunes for rigs, they are trying to save money on rubber bands. In fact stowlsess bag is not for free, also they have to spend another extra money.
Maybe it's the fashion? The owner of such stowless bag looks to be smarter then the rest of using normal D-bags. J

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In a very limited scenario, semi-stowless bags may have a place. (Personally I think fully stowless are a bad idea) If you're jumping ultra-high performance canopies then there's an argument to be made for reducing the shake of the bag as the lines deploy from rubber bands for deployment stability.

For everyone else they're a cool-factor, or a convenience.

Prove me wrong. Tell me why someone with a Spectre 150 is safer with a stowless bag than a traditional one.

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Dude, your canopy came out at freely speeds. No magnets on earth bar something that powers the Haleron Collider would keep that deployment normal. If you want to point a finger first... look at yourself for kit maintenance.
At long last the light at the end of the tunell isnt an on coming train!!!

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Just some food for thought about the fully magnetic gear bag, a friend of mine had a bag lock with a fully magnetic bag.
Which is quite contradicting to the discussion here about lack of closing power.

Not being an expert, I get the feeling that:
If used properly and deployed under normal conditions fully magnetic are just as good as standard bags.
Not packed properly or not deployed in standard conditions all bets are off, just as it would be with standard bags.

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Yes. Everything was like manual of the rig says. I can see the problem with the shape of BOC pocket, the hackey w/o lock and ZP pilotchute.
I don't feel smarter then manufacturer but I think that bigger pilotchute made from F111 could better work with hackey handle

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