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ZegeunerLeben

Continuous Disreefing Control System

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>>Dis-reefing is the act of slowing down the initial opening of a parachute, accomplished in sport parachuting via the slider, which dis-reefs in stages. The ideal disreefing device, however, is continuous. No one has as of yet come up with working canopy design that continuously deisreefs, and apparently it's the big puzzle in parachute design.

>>Ballistic Recovery Systems(BRS) has won a contract with NASA to develope a continous dis-reefing parachute system for entire jet-liners, to be deployed at over 250 knots. If successful, it could revolutionize sport parachuting also. Your canopy wouldn't need a slider or a d-bag, and could be deployed safely at nearly any airspeed. Staging the deployment/opening sequence would be less critical, and you wouldn't need different size PC's for different airspeeds. I was trying to imagine some designs for a continuously dis-reefing system, and browsing around on the web I came across an obscure pdf . I don't quite understand it all, but apparently they used a special 'disreefing line' and a sensor on the skirt that would theoretically provide continuous dis-reefing via feedback.

>>I personally wouldn't want to depend on a peice of gadgetry to keep my canopy from exploding, but it seemed an interesting solution. So what do you guys think? Any ideas for continuous dis-reefing out there?

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Pilot chute controlled "spider slider". The faster you are moving the slower the canopy opens.



>>I've never heard of a 'spider slider', how does that work?



It is a method of Pilot chute controlled reefing.
Pilot chute is attached to a slider, see attachment, by a long line that runs through the top and bottom skin of the canopy. When packing the line is pulled up through the canopy pulling the slider up to the stops. When you deploy the pull on the P/C is greater the faster you are going. As you slow down the P/C allows the slider to come down.
My idea of a fair fight is clubbing baby seals

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I don't believe it is used on any current manufactured canopy. Like the "ropes and ring" it used a standard pilot chute, spring type, and it was very bulky.



The last one I saw was on a ParaFoil 252, installed in a new Wonderhog and using the standard RWS throw-out pilot chute.

Mark

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I don't believe it is used on any current manufactured canopy. Like the "ropes and ring" it used a standard pilot chute, spring type, and it was very bulky.



The last one I saw was on a ParaFoil 252, installed in a new Wonderhog and using the standard RWS throw-out pilot chute.

Mark



I think you are right, Foils were the only canopies I have ever seen use the set up.

The one you describe above sounds scarey.

Sparky
My idea of a fair fight is clubbing baby seals

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I don't believe it is used on any current manufactured canopy. Like the "ropes and ring" it used a standard pilot chute, spring type, and it was very bulky.

Sparky



There was no requirement for a spring-loaded pilot chute.

I had a 189 ParaFoil with a spider-slider. I jumped it with a pullout pilot chute in an SST. It gave the smoothest openings I ever had. The downside was that the bridle passed through a grommets in the top and bottom of the center of the canopy. The bridle occasionally left friction burns in the top and bottom skins, and in the two ribs adjacent to the bridle.
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

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What type of material was this bridle?



IIRC, tubular nylon.

Mark



Right. The spider its self looked like a light harness webbing, (probably overkill). The rings at the end were welded stainless steel. I also saw some that were made with #8 grommets instead of the stainless rings.

Forgot to mention: You could adjust the rate of opening just by changing the size of the pilot chute. I was initially getting slammed when I used the pilot chute that came with the rig. When I complained to the mfgr he told me to use a 40". I had a 40" made and it gave silky smooth openings every time. I don't know why the mfgr didn't bother to include a note with a new canopy explaining that requirement.
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

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I can see how that would work but I have never heard of it before. Is the 'spider slider' in use on any in production canopy? just curious?



AFAIK it is still used one the Matrix CRW canopy made by IcarusNZ.
----------------------------------------------
You're not as good as you think you are. Seriously.

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I don't believe it is used on any current manufactured canopy. Like the "ropes and ring" it used a standard pilot chute, spring type, and it was very bulky.



The last one I saw was on a ParaFoil 252, installed in a new Wonderhog and using the standard RWS throw-out pilot chute.

Mark



>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Back in 1981, I made about 70 jumps on "ropes and rings" Strato-Clouds made by Para-Flite.
They were considered old technology by then.
They were a bitch to pack.
The fabric was tired and the ropes were a bit too short, so it was always a struggle to keep the end cells open.
Their one saving grace was their soft openings, even after tracking for a minute!

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AFAIK it is still used one the Matrix CRW canopy made by IcarusNZ.



The ParaFoil spider slider was attached to the pilot chute via a bridle that ran through the canopy. Is the Matrix spider slider similar? The web site says "lower surface pilot chute retraction", but it also says "brisk openings", which is what you would expect if the spider slider were slowed only by the aerodynamic drag on a couple pieces of webbing unconnected to the pilot chute.

Mark

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