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Im making a slider for an experimental canopy, does anyone know the ratio i should use for the span of the slider (width) to the width or span of the cell on a canopy? as in the distance between the center cell top cascade-canopy line attatchments?

thanks in advance...

CH

Im posting this here because BASE jumpers are open to these kind of things. usualy. plus, im banned from every other forum.

Just thinking aloud, but would the slider size also have some result from what sort of opening you were wanting to achieve?

It's different on different canopies. I'd start by measuring the most similar canopy you can lay your hands on (if it's a 7 cell, use your BASE canopy, for example, but if it's a 27 cell, find a swooping canopy at the DZ to measure) and using that ratio, then adjusting as you move through your testing process.

yes, of course. but i think that the span is the most important peice,,, im not sure though.
i remember reading here or the other forum that to change the effective area of a slider that it should be changed cordwise, not spanwise. the 'scoops' built into sliders only add to the nose to slow openings, right?

im just wondering what the rule of wrist is for sliders.

what if it is a 97 cell 220^2' canopy?

basicaly i am modifying a paraglider to be able to take the intial 70kt (ish) airspeed of a jump airplane. I have done some jumps on paragliders, only close to 0 airspeed dbags and rollovers though.

Try PMing or emailing Brian Germain. He's done a lot of paragliding and also designs parachutes...

...come to think of it, I'm pretty sure that once upon a time he busted himself up badly under a paraglider in dodgy conditions .

The slider is primarily driven down by the brake lines. Within reasonable limits, making the slider smaller can result in harder openings and vice versa. The angle between the brake lines and the slider is the driving force here, as a result of tail inflation and some slight bottom skin inflation with the help of stabilizer inflation.

makes sense.
the top 40% of the brake lines act at a higher angle to the slider. after it passes the brake cascade, I assume 90% of the driving force for slider movement is the outside lines from the tarps span.