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ryan_d_sucks

Connecting the D-Bag

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I just got a canopy with the same setup. I simply took a pair of bolt cutters and cut the ring off. Then you can hook up your d-bag with a rapid link where the ring was. Nice and easy lol



Just to be clear, depending on the configuration of the bag, the ring can be important if one wants to use a non-collapsible pilot chute on the canopy.

A non-collapsible pilot chute usually has a loop at the bag-end of the bridle that is large enough to allow using a lark's head to attach it to the ring. In that configuration, the ring is what pulls against the bag grommet to lift the bag. Without the ring, some of the canopy fabric could be pulled though the bag grommet when the pilot chute is lifting the bag. Exactly what will happens depends on the size of the bridle grommet on the bag.

If one ever wants to switch to using a non collapsible pilot chute, something may need to be done to make it function properly. It isn't hard; there are several things that can be done, but something should be done or damage to the canopy may be the result. Some bags have such a small grommet where the bridle goes through that it is not a problem. But some bags have quite a large grommet. These are the ones where you need to do something to make it work correctly.

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Who would want a non-collapsible PC? It was my understanding that the drag from the inflated PC will likely cause more damage to the attachment point than anything else while the canopy is in full flight.

I can understand someone who buy's used gear may encounter a non-collapsible PC (or maybe even a spring loaded rip-cord style), but that can be modded on most (if not all) of the rigs Ive seen. And a brand new kill line PC is only like $100 from paragear.
Muff #5048

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See how the bridle is not trailing behind the canopies? A crw bridle is basically a piece of dacron or microline, it runs through a few rings on the topskin of the canopy, canopy spreads out -> bridle gets spread out so seems shorter and the non-collapsible pilotchute (although sometimes these do have a kill-cone = piece of fabric to collapse it a bit) is pulled against the tail. All this to make sure you have no trailing "tail" which can entangle when you dock. This whole setup of course wouldn't work with a kill-line type pc.

http://www.vigil.aero/files/images/skydiving/skydiving-crw1.jpg

ciel bleu,
Saskia

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Who would want a non-collapsible PC? It was my understanding that the drag from the inflated PC will likely cause more damage to the attachment point than anything else while the canopy is in full flight.

I can understand someone who buy's used gear may encounter a non-collapsible PC (or maybe even a spring loaded rip-cord style), but that can be modded on most (if not all) of the rigs Ive seen. And a brand new kill line PC is only like $100 from paragear.



It somewhat depends on the canopy. Maybe you'll always own this canopy and never want anything different.

But -

I know a number of people who still jump non-collapsible pilot chutes.

I know some who wonder if a collapsible is worth the reserve rides they've had because of them.

There are other ways to kill a pilot chute besides a kill line.

Though some will deny it, a bungee collapsible can be quite acceptable. It is sort of like the dreaded velcro-stowed toggle, under the proper conditions either can work quite well.

Then there's the CF rigs that don't use the 1" Type IV tape for a bridle.

My point is that the ring was there for a reason. You might not need it now, but someone might have a need for it later.

If you ever came to have a need or interest in another configuration on this canopy, it might be useful to know why the ring was there in the first place.

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It is sort of like the dreaded velcro-stowed toggle, under the proper conditions either can work quite well.



I have velcro-stowed toggle's! And I agree that as long as you're diligent with your packing and setting the brakes then they are no problem at all (Ive never had one).
Muff #5048

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>Who would want a non-collapsible PC?

1) Less complexity, more reliable
2) Cheaper
3) Doesn't matter as much on larger canopies (like student canopies)

>It was my understanding that the drag from the inflated PC will likely cause
>more damage to the attachment point than anything else while the canopy is in
>full flight.

Compare the forces on that point during opening vs. during flight. They're not even close.

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Compare the forces on that point during opening vs. during flight. They're not even close.



Thats actually got me wondering. On a standard non-collapsible PC I would say that is definately true, but what about a collapsible one? What I mean is, on a collapsible PC it exerts force until the canopy comes out of the bag at which point it immediately collapses because the kill line allows it to. So I wonder does it actually put sizably more force on the attachment during deployment than in flight (the PC I mean)?

Not that it really matters at all. People have been jumping gear like this for quite a while without too many issues. I'm just one of those guys who likes to understand the physics of things, and forces involved.
Muff #5048

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Once the ring is off, what would be the diffrence between having the ring and using a ripid link in its place. Not trying to be a smart ass or anything. I like doing my own rigging and would like to know for future ref. BTW i'm flying a 135 elliptical so I dont think anyone will be putting a non collapsable pilot chute on in the future at least hope not

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Compare the forces on that point during opening vs. during flight. They're not even close.



Thats actually got me wondering. On a standard non-collapsible PC I would say that is definately true, but what about a collapsible one? What I mean is, on a collapsible PC it exerts force until the canopy comes out of the bag at which point it immediately collapses because the kill line allows it to. So I wonder does it actually put sizably more force on the attachment during deployment than in flight (the PC I mean)?

Not that it really matters at all. People have been jumping gear like this for quite a while without too many issues. I'm just one of those guys who likes to understand the physics of things, and forces involved.



I'm also a little confused about Bill's comment. Bill, are you saying the forces during opening are high compared to the forces during flight?

The canopy's pilot chute attachment point should not be taking the load of lifting the bagged canopy. The bridle should be effectively attached to the bag, and the bag does that lifting.

In the case of a non-collapsible pilot chute, or a bungee-collapsible, the ring on the attachment point should be stopped by the bag gommet. So the bridle pulls on the bag.

In the case of a kill line collapsible, the bridle should be attached to the bag. There are several ways that this might be accomplished. One is having a quick link inside the bag between the "wings" of the end of the bridle. UPT puts a giant mass of sewn tape at the end of the bridle that is hard to get though the grommet in the first place.

Either way, the bridle should be pulling on the bag during deployment, not the canopy's bridle attachment point.

In the case of a kill line, there is a moment as the canopy exits the bag when the pilot chute is still inflated and the force might get to the canopy's attachment point. That force would be greater than the collapsed pilot chute pulling on the attachment point, but it should only last a fraction of a second.

But I think that in most cases, the force of dragging the bag and pilot chute is higher than the force during opening, because a properly constructed system has the bag doing the lifting, not the canopy's pilot chute attachment point.

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Once the ring is off, what would be the diffrence between having the ring and using a ripid link in its place. Not trying to be a smart ass or anything. I like doing my own rigging and would like to know for future ref. BTW i'm flying a 135 elliptical so I dont think anyone will be putting a non collapsable pilot chute on in the future at least hope not



As I said

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If one ever wants to switch to using a non collapsible pilot chute, something may need to be done to make it function properly. It isn't hard; there are several things that can be done, but something should be done or damage to the canopy may be the result. Some bags have such a small grommet where the bridle goes through that it is not a problem. But some bags have quite a large grommet. These are the ones where you need to do something to make it work correctly.



I think it depends on the original configuration.

Maybe some master rigger has a better answer. If so, please chime in!

If it is a bridle attachment like a PD bridle attachment, where the ring is in the middle of the loop, and you attach the bridle to the webbing loop, I would pick out the bartack that held the ring and put a new ring there. Or you could use a quick link, which is easier. Be sure the quick link is big enough.

If the bridle is one where the ring is at the end of the webbing loop and you attach the bridle to the ring, I like putting a quick link there a bit less. I worry that it is more likely to trap some fabric between the link and the grommet, especially because the quick link has the barrel. If the webbing loop was large enough, I would try to lark's head a new ring to the loop. If I couldn't do that, I'd still try to find a way to attach a new ring.

As I said, I'd love to hear from some of the masters who are reading.

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