Breakable risers?

[mcrocker 0]

Would is make sense for people jumping tiny mains (21 sq foot for example) to have breakable risers? The fatality in AZ was caused by high G forces and the inability to cut away. What if the risers were weakened and designed to fail at a 500 lbs of force (200 lb person, 5 Gs = 500 lb force on each riser). If one of the risers broke, the spin would stop and the jumper would have been able to recover, cut away and deploy their 'landing main'.

Just a thought, not for normal jumping but for the 3 chute jumps involving a tiny main that will be cut away so a landable main can be deployed.

[jjiimmyyt 0]

I know jack about rigging, but wouldn't deployment cause the risers to break? Even if D'Bagged?

Repeat, I know jack about rigging.

"This isn't an iron lung, people. You can actually disconnect and not die." -Dave

[kelpdiver 2]

Might work for the test jumps where the canopy is deploy sub terminal, but certainly you run chance that it will break when you don't want it to. Difference between a hard flat turn and an uncontrolled spin is duration, not G forces up to a certain point.

Can you manufacture to that level of precision? Good, but not great?

In Incidents, someone suggested a cypres like device based on a g force sensor. Should be easier to create, though still non trivial for a small target audience.

[mcrocker 0]

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In Incidents, someone suggested a cypres like device based on a g force sensor. Should be easier to create, though still non trivial for a small target audience.

Maybe that would work better. Cut the 3-ring loop on the risers if there is a greater than X G force for Y seconds.

[billbooth 10]

Correctly made, and maintained, mini 3-ring risers will easily cutaway even under a 6 "G" spin, which by the way, would render the jumper unconscious in just a few seconds anyway.

[mjosparky 4]

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Correctly made, and maintained, mini 3-ring risers will easily cutaway even under a 6 "G" spin, which by the way, would render the jumper unconscious in just a few seconds anyway.

I think you called it Bill. His inability to cut away had nothing to do with the equipment. Considering the the radius of the spin, he was G-loc after 3 maybe 4 for revolutions.

Sparky

My idea of a fair fight is clubbing baby seals

[riggerrob 643]

Breakable risers would create more problems than they could solve.
First, since openings are rarely perfectly symmetrical, you would load one riser more than the other and break a lot risers during "firm" openings,

[j3zz 0]

Would it not be possible to just use a standard expert cypress 2 pin that cuts the loops as the real problem is downward speed eventually

ONe could set it like doing a high DZ jump so it would fire early?

I am not sure the amount of cable on the current 2 pin system but it could work.

Quetion though, could g forces achieved under a canopy kill one on there own?

Just a thinking aloud

Jezz

"Now I know why the birds fly"
Hinton Skydivers

[MarkM 0]

Think the easiest solution I've heard would be to use a student cypres with a round reserve.

[MakeItHappen 15]

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Correctly made, and maintained, mini 3-ring risers will easily cutaway even under a 6 "G" spin [snip].

This does not make sense to me. The G load would increase the loop load too. At some point the loop will break or the cable will kink. This can only be related to force magnitude, not Gs.

6Gs for a 100 pound person would be 600 pounds in the main lift web.
6Gs for a 200 pound person would be 1200 pounds in the main lift web.

I would think that the cable kinks at such-n-such a force, eg 223 pounds. or that the loop breaks at such-n-such force, eg 550 pounds.

Do you have a relationship between F_loop vs F_MLW, empirical or experimentally determined?

For instance if F_loop = 0.33 F_MLW and a 6 G scenario
the 100 pounder would have 198 pounds in the loop and the 200 pounder would have 396 pounds in the loop.

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Make It Happen
Parachute History
DiveMaker

[billbooth 10]

The three ring release divides the force put on the risers by a factor of up to 200, depending on which size 3-ring system you use. Go to Relativeworkshop.com and look at the 3-ring riser pull force chart. You will see that even a mini 3-ring system can easily handle a 600 pound load on each riser.

[peckerhead 0]

I remember making a joke about four years ago how someday jumpers would exit with absurdly small canopies with no intention of ever landing them.

No Shit!

They would just fly them around at high speed and then cut them away and deploy something that could be landed safely. The cutaway toy would have some high tech beacon to find and retreive it.

I never thought it would end in tradgedy like this, I honestly thought it could not be worse than jumping a board, and quite likely safer.

Just because we can push the limits of what is possible does that mean we should?


Baby steps people. You don't have to die to be a "pioneer"

Breakable risers=bad idea

Secondary automatic release? I would love to see this explored. I hate to rely on gadgets but I think this might be the next phase in aads.

An aad that can ALSO release a spinning malfuntion before firing the reserve?

Tough questions, what altitude, what speed, etc.

Welcome to the 21 century.

[riggerrob 643]

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I remember making a joke about four years ago how someday jumpers would exit with absurdly small canopies with no intention of ever landing them.

Breakable risers=bad idea

Secondary automatic release? I would love to see this explored. I hate to rely on gadgets but I think this might be the next phase in aads.

An aad that can ALSO release a spinning malfunction before firing the reserve?

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

Aparently a multi-cutter AAD was considered at the start of the CYPRES project, but the soft-ware was too complex, so Helmut Cloth focussed his efforts on de-bugging a 1-pin AAD.

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[mjosparky 4]

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I remember making a joke about four years ago how someday jumpers would exit with absurdly small canopies with no intention of ever landing them.

Breakable risers=bad idea

Secondary automatic release? I would love to see this explored. I hate to rely on gadgets but I think this might be the next phase in aads.

An aad that can ALSO release a spinning malfunction before firing the reserve?

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

Aparently a multi-cutter AAD was considered at the start of the CYPRES project, but the soft-ware was too complex, so Helmut Cloth focussed his efforts on de-bugging a 1-pin AAD.

Rob,

Remember Robert's reefing cutter? Rig them with a G load mechanism for pulling the pin on a 0 time cutter. Or go to a 30/40 sec. timed cutter and pull the pin on exit.
Use small ones for cutting the loops or the large cargo ones for cutting the risers.

Sparky

My idea of a fair fight is clubbing baby seals

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