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Type 17 risers.
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Meat.Missile

Jul 3, 2019, 12:14 AM
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Type 17 risers. Can't Post

I did a search and found no current discussions.

What is the opinion on type 17 risers being used for FAA compliant WS BASE?

TomAiello

Jul 3, 2019, 7:24 AM
Post #2 of 20 (727 views)
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Re: [Meat.Missile] Type 17 risers. [In reply to] Can't Post

What is FAA compliant WS BASE?

Are you taking a BASE rig out of a plane, with a front mount reserve? Or using a skydiving rig sized for a BASE canopy? What are the deployment altitudes?

Is your concern riser failure at opening on a deployment that is too low to activate the reserve?

Meat.Missile

Jul 3, 2019, 9:18 AM
Post #3 of 20 (704 views)
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Re: [TomAiello] Type 17 risers. [In reply to] Can't Post

TomAiello wrote:
What is FAA compliant WS BASE?

Are you taking a BASE rig out of a plane, with a front mount reserve? Or using a skydiving rig sized for a BASE canopy? What are the deployment altitudes?

Is your concern riser failure at opening on a deployment that is too low to activate the reserve?

Skydiving rig modified and sized for a BASE canopy. Concern is riser failure at opening.

bluhdow

Jul 3, 2019, 10:55 AM
Post #4 of 20 (688 views)
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Re: [Meat.Missile] Type 17 risers. [In reply to] Can't Post

There have been Type 17 riser failures in the past, in BASE and skydiving.

A few points which, I think, should be reassuring for anyone running them in the "FAA Legal WS BASE" arena these days:

1. The lack of elasticity in Spectra line kits may have been a contributing factor to these failures. Dacron should help absorb opening forces a lot better and reduce the potential for failures.

2. The geometry on Type 17 risers and Mini Rings has to be like...perfect. Small deviations from the correct geometry can change the strength of the risers (at the rings) meaningfully, and it stands to reason that modern skydiving risers are more precise and have better designs than the risers which have failed in the past.

3. Wingsuit opening speeds are lower and the opening forces are not as likely to create an issue as opposed to, say, a slick track.

Just pay close attention to your risers to check for wear. Especially at the 3 ring. And especially if you're running an old/tired/ragged container for those jumps because you didn't want to invest in a new system for a handful of special jumps.

TomAiello

Jul 3, 2019, 11:18 AM
Post #5 of 20 (680 views)
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Re: [Meat.Missile] Type 17 risers. [In reply to] Can't Post

If your opening altitude is high enough to allow reserve opening, I wouldn't worry about it.

If it's not, I'd personally go with a heavier riser, or at the very least a very frequent inspection. I'd probably measure the rings themselves with a some kind of caliper, to make sure that they aren't slowly distorting (bending) over time after repeated openings.

In the end, I think if I was at all worried, I'd just go with something heavier. If you're not sure, do whatever it takes to become sure.

bluhdow

Jul 3, 2019, 11:45 AM
Post #6 of 20 (673 views)
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Re: [TomAiello] Type 17 risers. [In reply to] Can't Post

TomAiello wrote:
In the end, I think if I was at all worried, I'd just go with something heavier. If you're not sure, do whatever it takes to become sure.

Apex builds Type 8 risers with mini rings (rear facing) which are compatible with skydiving rigs. When it comes to cutting away, rear facing risers are sub-optimal. But in this scenario it seems like the ability to cut away is sometimes already forfeited due to planned opening height.

It's an option if you want to run a stronger BASE-specific riser, and you understand that it could complicate your cutaway procedure if you ever intended to go to your reserve.

TomAiello

Jul 3, 2019, 12:18 PM
Post #7 of 20 (664 views)
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Re: [bluhdow] Type 17 risers. [In reply to] Can't Post

Have you guys pull tested those (type 17 risers) to failure?

I'm curious if the failure mode is related to the material difference. Nearly all the risers I've seen pull tested to failure have failed by kinking the yellow cable and pulling it back through (in various ways). it seems like that would happened regardless of the riser material, but I really don't know.

If you haven't, I'd be interested to get some and pull them to failure on our table and see how they fail.

Meat.Missile

Jul 3, 2019, 12:31 PM
Post #8 of 20 (660 views)
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Re: [bluhdow] Type 17 risers. [In reply to] Can't Post

Thanks, I will have to see if they are compatible with the rig design. Do you know a source for info on rear facing risers? I am not very familiar with them and google/dz/here is failing me.

I think the "ball of shit" theory applies to cutting away in this situation.

Meat.Missile

Jul 3, 2019, 2:16 PM
Post #9 of 20 (645 views)
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Re: [TomAiello] Type 17 risers. [In reply to] Can't Post

https://squirrel.ws/learn/risers

Squirrel has all this info. I feel like type 17 risers should be fine for slider up jumping.

bluhdow

Jul 3, 2019, 4:00 PM
Post #10 of 20 (636 views)
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Re: [TomAiello] Type 17 risers. [In reply to] Can't Post

Todd's memory suggests that there were Type 17 failures in the webbing, near where the grommet punched through the webbing. I think this area is reinforced now, so that's an issue probably more related to older designs as mentioned above. (With rear facing risers, there's no grommet punching through the webbing.)

More recently, I'm with you in thinking most of the failures occur within the 3 ring system itself (and not the webbing).

bluhdow

Jul 3, 2019, 4:01 PM
Post #11 of 20 (634 views)
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Re: [Meat.Missile] Type 17 risers. [In reply to] Can't Post

What kind of info are you after? I can usually chase Todd down to answer anything technical in nature.

DFR

Jul 3, 2019, 7:04 PM
Post #12 of 20 (616 views)
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Re: [Meat.Missile] Type 17 risers. [In reply to] Can't Post

I would be curious to see the numbers on what each break at. But I?m assuming you?re going to be using this for just wingsuit BASE and since most of my wingsuit BASE openings are just as soft if not softer than my non wingsuit skydive opening, and with the kind of jump numbers people put on skydive riders, I?m sure you?ll be fine realistically with them using them a fraction of those jumps whenever you?re doing a terrain flight from a plane or heli.

TomAiello

Jul 3, 2019, 7:26 PM
Post #13 of 20 (610 views)
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Re: [Meat.Missile] Type 17 risers. [In reply to] Can't Post

Meat.Missile wrote:
Thanks, I will have to see if they are compatible with the rig design. Do you know a source for info on rear facing risers?

Parachutes de France is the only manufacturer I'm aware of that makes rear facing type 17 risers for skydiving. It's possible that my knowledge is out of date (so they might not make them any more) but I know I've seen PdF risers that faced rear.

There was a fatality in Australia because of a mis-match between the riser type and the the container (my memory may be faulty but I believe it was PdF risers on a Naro container) which caused a failure to separate when the cutaway handle was pulled, and a resulting main/reserve entanglement.

Meat.Missile

Jul 3, 2019, 8:06 PM
Post #14 of 20 (603 views)
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Re: [DFR] Type 17 risers. [In reply to] Can't Post

DFR wrote:
I would be curious to see the numbers on what each break at. But I?m assuming you?re going to be using this for just wingsuit BASE and since most of my wingsuit BASE openings are just as soft if not softer than my non wingsuit skydive opening, and with the kind of jump numbers people put on skydive riders, I?m sure you?ll be fine realistically with them using them a fraction of those jumps whenever you?re doing a terrain flight from a plane or heli.

That was my thinking as well.

TomAiello

Jul 3, 2019, 9:17 PM
Post #15 of 20 (597 views)
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Re: [DFR] Type 17 risers. [In reply to] Can't Post

DFR wrote:
I would be curious to see the numbers on what each break at.

My gut feel is that basically any current production riser system fails at "so high it doesn't matter".

But I'd love to do some more pull testing and see if we can find what the weaknesses are. The Squirrel "double yellow cable" riser is a direct way to address the primary failure mode (kinked yellow cable) but I wonder what else we might learn.

DFR

Jul 3, 2019, 9:36 PM
Post #16 of 20 (591 views)
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Re: [TomAiello] Type 17 risers. [In reply to] Can't Post

TomAiello wrote:
My gut feel is that basically any current production riser system fails at "so high it doesn't matter".

But I'd love to do some more pull testing and see if we can find what the weaknesses are. The Squirrel "double yellow cable" riser is a direct way to address the primary failure mode (kinked yellow cable) but I wonder what else we might learn.

Agreed. If people want to send me hardware, I have access to a free break test machine and can break as much stuff as needed.

AntoineLaporte

Jul 8, 2019, 11:57 PM
Post #17 of 20 (406 views)
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Re: [TomAiello] Type 17 risers. [In reply to] Can't Post

TomAiello wrote:
Meat.Missile wrote:
Thanks, I will have to see if they are compatible with the rig design. Do you know a source for info on rear facing risers?

Parachutes de France is the only manufacturer I'm aware of that makes rear facing type 17 risers for skydiving. It's possible that my knowledge is out of date (so they might not make them any more) but I know I've seen PdF risers that faced rear.

There was a fatality in Australia because of a mis-match between the riser type and the the container (my memory may be faulty but I believe it was PdF risers on a Naro container) which caused a failure to separate when the cutaway handle was pulled, and a resulting main/reserve entanglement.

If I remember well we got a fatality in France because of rear facing risers and the possibility of a 3-rings lock that comes with it if the 3-rings are in tension and in the same kind of position as when it is packed (I hope you understand what I mean)

TomAiello

Jul 9, 2019, 7:43 AM
Post #18 of 20 (381 views)
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Re: [AntoineLaporte] Type 17 risers. [In reply to] Can't Post

AntoineLaporte wrote:
If I remember well we got a fatality in France because of rear facing risers and the possibility of a 3-rings lock that comes with it if the 3-rings are in tension and in the same kind of position as when it is packed (I hope you understand what I mean)

Yes, I understand. The rear facing rings can get trapped against the jumpers chest during a high speed malfunction, rendering them unable to release.

I actually demonstrate and teach about this problem in courses, because students sometimes want to take the shortcut of putting their (rear facing) BASE risers onto a skydiving rig to practice flying their BASE canopies. We emphasize that the risers are a component of the container, and that you should not simply move them between BASE and skydiving containers.

MrAW

Jul 10, 2019, 4:28 AM
Post #19 of 20 (289 views)
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Re: [TomAiello] Type 17 risers. [In reply to] Can't Post

I think that the PdF container construction has the harness ring placed higher on the main lift web to allow proper function of reverse risers. So they work fine on PdF containers but other skydiving rigs have the malfunction mode you have described.

Relevant APF service bulletin:
https://www.apf.com.au/...10a.pdf.aspx?Embed=Y

TomAiello

Jul 10, 2019, 10:10 AM
Post #20 of 20 (262 views)
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Re: [MrAW] Type 17 risers. [In reply to] Can't Post

Correct. The problem occurs when a PdF riser is swapped onto a non-PdF container. A similar problem is possible when a reversed BASE riser is swapped onto a standard skydiving rig.

Risers are a component of the container, and as a general rule should not be swapped between containers.


(This post was edited by TomAiello on Jul 10, 2019, 10:11 AM)


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