what is next....

[Bartje 0]

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Nope. Wing structures (leading edge, bracing, etc) inflated with an external high-pressure source look like a nice idea for purpose-built swooping canopies (nose-down trims, detachable slider/pilot chutes, etc. are already taking us down this path).

Still the Rage sounds like that. Closed nose; high pressure airlocks, nose down (closed, just open in front, just after the nose)

A FreeFly Gypsy

[DrewEckhardt 0]

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Nope. Wing structures (leading edge, bracing, etc) inflated with an external high-pressure source look like a nice idea for purpose-built swooping canopies (nose-down trims, detachable slider/pilot chutes, etc. are already taking us down this path).

Still the Rage sounds like that. Closed nose; high pressure airlocks, nose down (closed, just open in front, just after the nose)

Not as in "the user jumps with an air tank."

A couple PSI is going to beat what's in front of a canopy flying at ludicrous speed like Luigi's 39. We have quick disconnect fittings for hundreds of pounds and SCUBA tanks are good for thousands of pounds.

Although your planform and other parameters are limited by deployment,you could effectively match a solid wing's rigidity.

People have demonstrated various inflatable wings and the kite guys now have inflatable leading edges. Some one is going to apply the technology to canopies.

[AggieDave 6]

At that point I bet there's altitude restrictions for the air delievery system, to keep them from going boom in the jump plane.

I wonder how large of an enclosed canopy 6 of those little CO2 canisters (like in air guns/quick bicycle tire pumps) would fill to a pressure slightly higher then the outside air (yes I understand the differences in air density throughout temperature changes and all the other crap...this is just an over generalization).

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

[DrewEckhardt 0]

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At that point I bet there's altitude restrictions for the air delievery system, to keep them from going boom in the jump plane.

I wonder how large of an enclosed canopy 6 of those little CO2 canisters (like in air guns/quick bicycle tire pumps) would fill to a pressure slightly higher then the outside air (yes I understand the differences in air density throughout temperature changes and all the other crap...this is just an over generalization).

Atmospheric pressure is about 14.7 PSI. The pressure differential isn't going to get that high until you're in space where a wing won't work. Even there it's not going to be a dangerous over-pressure.

Filling the entire canopy is unlikely to work - you'd need to build it without stiching holes (adhesives, plastic welding, etc. could work arround that), use a vacuum to pack it, come up with absurdly thin/strong materials to fit it in a container (substantial pressurization into > 50 cubic feet is going to take strong, thick materials), and keep it deployable.

Inflatable frames, spars, etc. are a different story. 1" diameter tubes made from synthetic fabric (kevlar, etc.) with air-tight bladders (latex) woudln't add too much bulk compared to the reinforcing tapes used on reserves and Big Air canopies and their flexibility is not going to cause deployment problems.

[AggieDave 6]

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nflatable frames, spars, etc. are a different story. 1" diameter tubes made from synthetic fabric (kevlar, etc.) with air-tight bladders (latex) woudln't add too much bulk compared to the reinforcing tapes used on reserves and Big Air canopies and their flexibility is not going to cause deployment problems.

Nice, hadn't thought of that.

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

[Bartje 0]

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People have demonstrated various inflatable wings and the kite guys now have inflatable leading edges. Some one is going to apply the technology to canopies.

Perhaps my english is no that good in technical terms but is this not the combination what you mean? http://p4961.typo3server.info/fileadmin/user/pdfs/The_Rage_Principle_A4.pdf

A FreeFly Gypsy

[skygod7777 0]

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but is this not the combination what you mean?

a little while back this was discussed, i think the biggest problem would be the constuction, i'm not sure if you could make a canopy cross braced with that type of nose constuction........i mean, i may be eating my words, but it seams it would be very difficult to build



but then again, brain germain built the sensi which is crossbraced and airlocked (not quite the same though)


later

[kelpdiver 2]

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At that point I bet there's altitude restrictions for the air delievery system, to keep them from going boom in the jump plane.

A bright sun can raise the pressure of a tank 100psi or more. That's still only 3%. Filling it too fast might be 200psi until it cools down.

The biggest change from altitude would be less than 14.7, so it's a total non issue with regards to pressure. Main concern would be protecting the valve - potential energy is somewhat akin to a cadillac hitting a wall at 100mph.

[Bartje 0]

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it seams it would be very difficult to build

I think it is ready,
last summer at Spa the Paratec FreeFly team was training and they are jumping the Rage. They told it would be rready by the end of 2004 but I did not hear anything yet. Perhaps it is like you said, very difficult to build.
I'm going to look for more news.

A FreeFly Gypsy

[DrewEckhardt 0]

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People have demonstrated various inflatable wings and the kite guys now have inflatable leading edges. Some one is going to apply the technology to canopies.

Perhaps my english is no that good in technical terms but is this not the combination what you mean? http://p4961.typo3server.info/fileadmin/user/pdfs/The_Rage_Principle_A4.pdf

No. Like a bicycle tire or air mattress. You could get 100 or 1000X the pressure you get from the wing moving through the air.

[skygod7777 0]

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I think it is ready,
last summer at Spa the Paratec FreeFly team was training and they are jumping the Rage.

yes the RAGE is ready, i have jumped it, the 107 and the 97..........but that design with crossbraces would be very difficult to build.


later

[skygod7777 0]

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No. Like a bicycle tire or air mattress. You could get 100 or 1000X the pressure you get from the wing moving through the air.

how would you seal the stiches??? each time a needle goes thru the fabric it make a very small hole, and air does get out........so even if you could pump it up, how could you keep it inflated that way at all times without having to continually pumping (granted it doesn't let much air out, but it still does).


later

[Bartje 0]

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how would you seal the stiches???

A good glue or birdlime can do miricals

A FreeFly Gypsy

[skygod7777 0]

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A good glue or birdlime can do miricals

i'm not sure what birdlime is, but glue *could be i'm not sure be bad for the canopy..........and me personally (i don't know many glues granted) but don't glues dry hard???? so how would you pack it without cracking the glue


later

[Bartje 0]

Birdlime, or birdglue, is a glue what stays flexible when it is dry.

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i'm not sure what birdlime is, but glue

If you make a new canopy than I will not use fabrics but plastics.

In the past I saw competition swimmers with a suit where the fabric was not always at the same direction maded. It looked as stripes. The advantage was that the water was less turbulent when it passed over the body.
Is that not an idea for a canopy. A fabric that made so the airflow is less turbulent?

A FreeFly Gypsy

[mccurley 1]

Inflatable frames, spars, etc. are a different story. 1" diameter tubes made from synthetic

Good idea I think and like anything else, probaly only difficult the first time.

This whole thread takes me back to grade 7 that whould be 1966, I recall seeing (in popular mechanics or popular science, a glider which was an airfoil much like modern canopies, suspension lines and all, but fully enclosed and inflated with helium! Ment to be ground launched as a glider.

It obviousley caught my imagination or I wouldn't remember it now.
No idea how it flew.

Watch my video Fat Women
http://www.youtube.com/watch?v=eRWkEky8GoI

[Brains 2]

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i'm not sure what birdlime is, but glue *could be i'm not sure be bad for the canopy..........and me personally (i don't know many glues granted) but don't glues dry hard???? so how would you pack it without cracking the glue

You are still thinking ZP. There IS a canopy out there made of kevlar reinforced plastic by 3M. All seams are sealed with heat tape. It is incredibly light(the lineset weighed more than the canopy) and packs up considerably smaller than other lesser sq. ft. mains. Downside to this particular one was that it opened like shit, so i was told, (and saw)

Never look down on someone, unless they are going down on you.

[Joyner 0]

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In the past I saw competition swimmers with a suit where the fabric was not always at the same direction maded. It looked as stripes. The advantage was that the water was less turbulent when it passed over the body.
Is that not an idea for a canopy. A fabric that made so the airflow is less turbulent?

Interesting point. I'm not sure how much the laminar airflow contributes to drag. I'm sure things like lines, skydiver, slider, pilot chute and bag generate a whole lot more parasitic drag than the direction of the fibers of the fabric. But being short of a revolutionary change in design every small thing you can improve does make a small difference.

On the other hand when I learned aerodynamics (10 years ago), I learned that you are actually dependent on a very thin turbulent laminar airflow to generate lift. Sort of along the lines that a perfectly smooth surface would not generate as much lift as a surface just a little bit rough (we are talking on a microscopic level). I know that a lot has happened in the field of aerodynamic research since. Anyone have any input on this.

[kelpdiver 2]

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On the other hand when I learned aerodynamics (10 years ago), I learned that you are actually dependent on a very thin turbulent laminar airflow to generate lift. Sort of along the lines that a perfectly smooth surface would not generate as much lift as a surface just a little bit rough (we are talking on a microscopic level). I know that a lot has happened in the field of aerodynamic research since. Anyone have any input on this.

I believe that is where competition swim suits are at these days - effectively "shark" skins. But the effect doesn't last long - ideally you'd want a new one for the big meet. Kind of a shame - swimming was one of the cheapest sports out there for equipment concerns. I'd like to see it restricted to speedos and a swimcap.

Probably not ideal for skydiving to use a fine sandpaper like finish, unless you can find away to keep the top and bottom skins from rubbing during packing and opening.

[Bartje 0]

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Interesting point. I'm not sure how much the laminar airflow contributes to drag

It create an very thin layer turbulance where the air has less resistance.
The surface, the roof of a canopy, is perhaps not big enough to make a lot of differance but maybe it is something for the birdman. The speeds are higer and so as well the effect perhaps.

A FreeFly Gypsy

[Joyner 0]

[reply
I believe that is where competition swim suits are at these days - effectively "shark" skins. But the effect doesn't last long - ideally you'd want a new one for the big meet. Kind of a shame - swimming was one of the cheapest sports out there for equipment concerns. I'd like to see it restricted to speedos and a swimcap.

Probably not ideal for skydiving to use a fine sandpaper like finish, unless you can find away to keep the top and bottom skins from rubbing during packing and opening.