lazy main deployment bag in Javelin

[indradhanush 0]

today i came across belgian natioanl team javlins rigs with lazy main deployment bag.. is it legal..
the breif discription about the bag is there is no rubber bands instead there is nylon tape similar to toggle width stitched to the place where rubber bands loops are loacated. on the other end there is pocket stitched which houses the 10 cm long 5mm width toggle like structure, that is the moth lock for the bag, and the rest is stowed in fig of 8 like reserve free bag, my queation is ... it legal. when i enquired one of the rigger makes these lazy bags.
as wea re aware about the problem of omega rigs where line getting around flap and one person killed. before we blame the manufacturer do u guys think we are also responsible not do modification on time tested design... please post ur vies.
santhosh

life is a daring adventure or nothing at all

[Hooknswoop 19]

There is no such thing as an illegal main deployment bag in the U.S., they are not TSO'd.

Derek

[riggerrob 558]

You just described a prototype main deployment bag that Sun Path built for several teams training in Florida.
Since they could never make the experimental d-bag skydiver-proof, it never got into production.
It is rumored that the experimental d-bag only worked gracefully with one size of canopy.

[mjosparky 3]

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Since they could never make the experimental d-bag skydiver-proof,

Nothing used in skydiving can be made "skydiver-proof".

Sparky

My idea of a fair fight is clubbing baby seals

[DexterBase 0]

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It is rumored that the experimental d-bag only worked gracefully with one size of canopy.

How could that possibly be true? I read this and then sat for a couple minutes pondering how that could be. I'm at a loss. Any ideas?

[sundevil777 94]

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It is rumored that the experimental d-bag only worked gracefully with one size of canopy.

How could that possibly be true? I read this and then sat for a couple minutes pondering how that could be. I'm at a loss. Any ideas?

It is just that the fold over flaps require a certain amount of tightness and distance to the mating pocket - the geometry has to be right.

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

[DexterBase 0]

That's wild that only one size of canopy would provide that amount of tension. I guess it's not a very dynamic setup then. Why not just use a freebag like a skydiving reserve?

[FrogNog 1]

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That's wild that only one size of canopy would provide that amount of tension. I guess it's not a very dynamic setup then. Why not just use a freebag like a skydiving reserve?

Most skydivers like to be able to repack their mains without having to first search through corn fields to find their deployment components. That's why our bags are tied to our canopies, i.e. they are not "free".

If you mean to ask why the rubber-bandless bags don't just use a pair of rubber band-based locking stows to close the bag (which would make it possible to keep the bag closed with more than a single "perfect" canopy size), and stow the rest of the lines in a pocket by carefully folding them, reducing the quantity of rubber bandage used in the same manner as a reserve bag, there are some people who have done that with their own deployment bags. But it's a halfway measure: the number of rubber bands is reduced but not brought to zero.

Back to the issue of why it requires a "perfect" size of canopy to keep these locking stowless bags properly closed: a bag has to be locked closed somehow, or the canopy will either escape during packing or at the start of deployment, when the pilot chute attempts to lift the bag (which contains a heavy canopy) out of the container. One way to lock bags is with rubber bands that go through grommets and around lines. Another way is with tuck tabs, similar to how some riser covers and pin covers close.

A bag closed with bights of line passed through rubber bands passed through grommets is opened when the bights are extracted from the rubber bands, or when the bands break.

A bag closed with tuck tabs has to be opened by pulling on the bag hard enough that the tabs' holding ability in their pockets is overcome. However, we don't want the tabs to pop out of their pockets immediately after the pilot chute pulls the pin and accelerates the bag off the jumper's back. So the tabs have to hold tight enough to keep the canopy in when the bag is yanked at first, yet hold loose enough that the bag will open when it gets to the end of the lines and now the pilot chute is attempting to accelerate the jumper as well as the canopy, via the taught suspension lines between them.

To make this happen, the bag is sized so when it is stuffed correctly, the tabs' grip will be within a proper range - not too weak, and not too strong. If the bag is overstuffed, the tabs could hold on too strong because their noses can't "push" the bag contents out of the way so they (the tabs) can exit their pockets. If the bag is understuffed, the tabs might not hold on strong enough, and the resultant deployment would be similar to having no bag at all.

Rubber band bag closure is more adaptable. But once there are two rubber bands to continually replace, I guess most people would go ahead and add more bands to use for stowing the rest of the lines.

Note: from a practical perspective, there are few people less expert about these bags than me. I've never made, jumped, or sewn one. But this is my understanding about how these work, from what I've read here. (Yeah, if you read it on dropzone.com, it must be true.)

Now, if someone comes up with another way to keep the bag closed and open it at the right time, we may have something. The tricky part is reliably telling the bag-locking device when line stretch has been reached. I suppose we could attach a curved pin to one of the suspension lines and close the bag with a loop through one or more small grommets.

-=-=-=-=-
Pull.

[DexterBase 0]

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Most skydivers like to be able to repack their mains without having to first search through corn fields to find their deployment components. That's why our bags are tied to our canopies, i.e. they are not "free".

(Thanks for the lengthy explanation of the obvious)

Why must the bag automatically be assumed to detach from the canopy after deployment? Does your current deployment bag do that?

I'm talking about a bag with a bungee locking stow and the remainder of the lines stowed in a tailpocket, something between a reserve freebag and a tailpocket on a BASE canopy.

Basically, you can modify deployment bags all day long and come up with a hundred ways to do things. In the end, you're not going to come up with a system that's as easy to use, and reliable as what we are all currently using.

What is the reason behing trying to come up with a system that uses fewer rubberbands? Saving time by having to replace broken bands less frequently? If so, then cutting the number of bands down to two will save a ton of time, over the course of a couple years of jumping. That's why I don't agree that if the total number of bands isn't zero, then you might as well just have ten. That makes absolutely no sense.

What is the end goal? To have a bag with no rubberbands to replace, but is simple enough to use that you don't end up spending just as much time stowing the lines another way?

I don't think it's going to be easy to do. For now you have to pick one. Spend more time stowing the lines, or continue to replace the rubberbands as necessary.

[indradhanush 0]

Dear friend well said,, no need to reinvent the wheels.. i share the same opnion... i am packer some times i pack 60-80 parachutes i never mind repalcing them rather than doing easy way lazy bag..

blue skies
santhopsh

life is a daring adventure or nothing at all

[jurgencamps 0]

If you copy it, it is illegal. The lazybag is patented. More info at: www.compal.be

[mjosparky 3]

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If you copy it, it is illegal. The lazybag is patented. More info at: www.compal.be

The web site makes no mention of a patent or a patent number. If someone does hold a patent on this bag, where was it granted?

Sparky

My idea of a fair fight is clubbing baby seals

[jurgencamps 0]

Where to look for patents? I don't know. The site only explains the lazybag and where to buy it. But you can always ask Luc Masin (E-mail : [email protected]). I know that the lazy bag is tagged with a small label (Compal), but I do not know if this label also shows the patentnumber.

[phoenixlpr 0]

I couldnt find any info where to get it.
I've checked those links on that site.
Anyway I was told that these kind of d-bag is not allowed to use in Finland due to some old accident. I like the idea, but I think I can not try it :(.

[Hooknswoop 19]

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If you copy it, it is illegal. The lazybag is patented.

Even if it is patented, you can still make one, you just can't sell them.

Derek