Drogue improvement

[Harksaw 0]

It seems that the drogue is the most fragile part of a tandem system, and this seems to me to be due to all the mesh. Why don't they make drogues that are made out of all zero-P with a hole at the bottom (like some reserve pilot chutes) ?

Would this be legal (for a rigger to make and add on) and/or feasible?

__________________________________________________
I started skydiving for the money and the chicks. Oh, wait.

[AggieDave 6]

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It seems that the drogue is the most fragile part of a tandem system

What brought you to that conclusion?

As I've seen in my short 5 1/2 years of jumping is that each component of a tandem system as a duty life and once that duty life is reached it should be replaced. Same with the drogue. With that said, every drogue that I've seen maintained to correct standards, manufactured correctly and replaced when stated to do such has performed correctly and as planned.

Have you experienced something different in your skydiving career that has shown that current drogue design is incorrect and causing problems?

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[Squeak 17]

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Quote

It seems that the drogue is the most fragile part of a tandem system

What brought you to that conclusion?

As I've seen in my short 5 1/2 years of jumping is that each component of a tandem system as a duty life and once that duty life is reached it should be replaced. Same with the drogue. With that said, every drogue that I've seen maintained to correct standards, manufactured correctly and replaced when stated to do such has performed correctly and as planned.

Have you experienced something different in your skydiving career that has shown that current drogue design is incorrect and causing problems?

wow dAve you read a lot more into apost than I do
From Harksaws post I got that he beleves the drogue to be the most "fragile" component, not that there is a problem with the drougue.
I read that he is wondering if you couldmake a drogue out of all ZP in order to make it less frail, not to make it work better.
But as always I could very wrong

You are not now, nor will you ever be, good enough to not die in this sport (Sparky)
My Life ROCKS!
How's yours doing?

[AggieDave 6]

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wow dAve you read a lot more into apost than I do

Maybe so...I'm very curious as to what types of specific design changes he was thinking of, especially since this is how some cool new ideas have started in skydiving. Starting with a "what if..."

It was definately not an attack on his thoughts and ideas, I just want some specific information.


Personally I think the most fragile component of tandem systems is a lack of proper maintance and mistakes by the TI, but I know that there is a lot of room for new design with tandem systems on the market...I just have no idea what that may be. A new design ZP drogue might be a step in the right direction or may lead to a new idea as such...we'll see, you never know.

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[Harksaw 0]

Well, it just seems that the drogue's duty life is shorter than it could be. Just about every drogue I've seen has rips and sewing all over it, mostly on the mesh. Why not make one that lasts longer?

I know that the Strong manual lists both the canopy and the drogue at lasting somewehre around 600 jumps, and from what I see, the drogue usually gets replaced long before the canopy.

What my idea was is using a design more similar to the Vector reserve pilot chute, without the spring. Have it shaped similarly to the drogue as is, but with the mesh replaced with zero-P with a hole in the bottom for air to come in.

Now that I think about this some more, maybe the vents on the top of the droge (and airflow through the drogue in general) are more critical than I thought in keeping the drogue from wobbling back and forth in freefall.

__________________________________________________
I started skydiving for the money and the chicks. Oh, wait.

[MikeForsythe 0]

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you never know

Want to bet?Hope life is treating you well!

Time and pressure will always show you who a person really is!

[AggieDave 6]

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Want to bet?

Care to fill us in then, or is it a corporate secret, G-14 classified?

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Hope life is treating you well!

Very, very well actually. A lot of very positive things have happened in my life this year and next year is looking just as good. Thanks for asking.


Ok, as for the patches in the mesh on drogues, I can't remember the last time I saw patches in a Sigma drogue but it seems like Strong drogues have patches all over every time I see one. I'm not sure if this is due to the construction, design or just dumb luck of the systems I've personally seen.

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[MikeForsythe 0]

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Care to fill us in then, or is it a corporate secret, G-14 classified?

I can not confirm or deny the presence of a UFO in my office. Just remember that for probably every ten things that we try in the shop maybe one will see daylight for testing. Except for maybe when we are doing the secret night test jumps out of the stealth black helicopter!

Time and pressure will always show you who a person really is!

[billbooth 10]

To be reasonably "stable", drogues need some sort of venting around their "equator". I tried a no-mesh drogue years ago (similar to a Vector reserve pilot chute). It orbited above me in wildly osccillating eight foot circles. It was quite a ride. The other reason all holes in our drogue are covered with mesh, is that TM's often have to dump their reserve pilot chutes past a drogue in tow, and I don't want any snag points to catch that reserve pilot chute.

It is a lot of extra work to "mesh in" all drogue openings, so we only do it because we have to. We use the toughest mesh we can find, and quite often it outlasts other parts of the drogue.

[billvon 3,116]

>As I've seen in my short 5 1/2 years of jumping is that each
>component of a tandem system has a duty life and once that duty
>life is reached it should be replaced.

Right. And if someone comes up with components with longer duty lives, that would surely be a good thing.

>Have you experienced something different in your skydiving career
> that has shown that current drogue design is incorrect and causing
> problems?

We also saw quite a bit of wear on the drouges. Drouges and drouge bridles were the most often replaced items on our tandem rigs.

[mjosparky 4]

What other component of a tandem rig supports the weight of 2 bodies at 120+ mph for 40/60 seconds every jump?

The P/C on a sports rig is one of the most often replaced components and its exposure to terminal speeds is just a fraction of a tandem drogue.

While testing a new system for the P-3 at Yuma I had the opportunity to observe a drogue similar to what Bill described. It was almost twice the diameter of a tandem drogue and made entirely of ZP. With a 376 pound, 6’ 7” test dummy it jumped around so much I was afraid to get close to it in freefall. It would randomly oscillate 6 to 7 feet off center line with the dummy oscillating 4 to 5 feet.

Sparky

My idea of a fair fight is clubbing baby seals

[riggerrob 643]

Strong used to make drogues with 1.5 oz. rip stop fabric, but they were too durable.
Length of life of drogues is directly related to user technique.
I remember one SoCal TI would always waited until he felt the bridle "horse shoe." We were always sewing patches on his drogues where F-111 fabric rubbed on the Kevlar bridle.