Internal BOC Bridle Sleeve (or whatever the hell else you want to call it)...

[lifewithoutanet 0]

While sitting atop a snowy wall this afternoon, simultaneously cursing both my good judgement and the wind, another jumper and I got to talking about the relatively new concept of adding an additional, internal pocket to the BOC for staging the bridle separately of the PC. I'm not sure which manufacturers are going with this design at this point--if any--but I do know it's been discussed recently.

On a positive note, this stages the bridle independently of the PC. When pitched, this internal pocket removes certain possible shit from going wrong in that the bridle reaches bridlestretch gradually, by the snatch and then drag of the PC, rather than exposing potential slack of the bridle to wraps or knots as the bridle reaches tension.

On a negative note, this stages the bridle independently of the PC. When pitched using such an internal BOC stow, the pitch of the PC will only extend the bridle to just beyond the arm-length of the jumper (accounting for some momentum of the outward throw--though nominal, given the relatively little mass of a PC itself) and some additional force exerted on the bridle by relative wind (also nominal, though increasing with delay) before the PC itself is snatched by the relative wind.

(*Note: different PC packing methods will have different effects, such as ensuring the "handle" exposed by the cap of the PC includes some bit of the bridle within the resulting ball of PC topskin.)

It would seem to me that by introducing an additional stow-point it could therefore induce hesitations, such as the bridle incurring friction or--worse--snag along the corner of the internal sleeve.

In any case, I'd like to get some thoughts on this internal BOC bridle sleeve and find out who (if any) manufacturers are using it or planning to use it and why.

Thanks.
-C.

[basehoundsam 0]

It came standard on my WS- Extreme . I have used a bunch with no noticable hesitation.

Jay Epstein Ramirez
www.adrenalineexploits.com

[TomAiello 25]

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I'm not sure which manufacturers are going with this design at this point--if any...

Morpheus, certainly. I think that Rob at Morpheus developed it.

I've watched video of it in action, and played around with it a fair bit.

My personal opinion at this point (based on perhaps 15 jumps on it, and slow frame video) is that it is a damn good idea. It's pretty much like a tail pocket for your bridle. It stages the bridle in the same way you want to stage the lines.

I'll write more later when I have more time.

-- Tom Aiello

[email protected]
SnakeRiverBASE.com

[lifewithoutanet 0]

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It came standard on my WS- Extreme . I have used a bunch with no noticable hesitation.

I can understand it's use and lesser hesitation potential on terminal and longer delay jumps. Do you know if it's an option on the standard Gargoyle? Guess I'll check in w/ Rob.

Thanks.
-C.

[GeordieSkydiver 0]

[replyI'll write more later when I have more time.

[pringles 0]

Here is a pic from the Morpheus web site.

Matt Davies

[yuri_base 1]

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It's pretty much like a tail pocket for your bridle. It stages the bridle in the same way you want to stage the lines.

Why isn't this pocket installed on PC's end of the bridle, much like a tail pocket on the canopy? With existing setup, I can see the potential for PC hesitation in small delay jumps if the bridle snags around the bottom corner of the container, turning this pocket into additional force distribution point (like 3-ring): corner - one, pocket - two, bridle tucked under the flap - three, and pin - four. Besides causing hesitation, this off-center force can quickly rotate the jumper towards the object, if he is in head high position during deployment.

I wonder if a safer solution would be to simply install small pieces of velcro on the bridle at regular intervals. S-fold the bridle, mating the velcros, and put inside the mushroom.

Yuri

Android+Wear/iOS/Windows apps:
L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP
iOS only: L/D Magic
Windows only: WS Studio

[PeteS 0]

About four years ago I played with the idea of a pocket on the bridle, made a couple samples. The people around here thought it was too much hassel to pack. Maybe attitudes are changing in regard to exta steps/benefits with regard to deployment issues?

[TomAiello 25]

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Why isn't this pocket installed on PC's end of the bridle, much like a tail pocket on the canopy?

I've played with that, too, a little, but haven't had time to actually build anything. I'm not sure if Rob (or anyone else) has done any testing with it.

I found that it was difficult to create a "bridle pocket" with minimal hang-up potential (the fact that it's wobbling makes it harder to predict extraction direction and encourage clean feeding, making it much more challenging to create a good setup) and that doesn't effect the inflation of the PC (because if you don't want the pocket to wobble, you will eventually try attaching it to the PC itself, which looked to be a pretty bad idea when I played with it).

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I can see the potential for PC hesitation in small delay jumps if the bridle snags around the bottom corner of the container

I can see that also. The easiest way to avoid this is to do short delay jumps hand held, and route the bridle over the shoulder.

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I wonder if a safer solution would be to simply install small pieces of velcro on the bridle at regular intervals. S-fold the bridle, mating the velcros, and put inside the mushroom.

I tried that, too, as well as using a tailgate rubber band to gather the bridle together.


So far, the Morpheus bridle staging pocket is, in my opinion, the best thing going. That doesn't mean we can't improve on it, though.


I'm not sure that the canopy tail pocket is the right place to look for a model, though. Things are different in the two systems to a significant degree. And don't forget that we usually deploy round canopies with the lines stowed in the pack tray, rather than on the parachute.

-- Tom Aiello

[email protected]
SnakeRiverBASE.com

[helge 0]

Could someone explain a dumb fucker whats wrong with todays setup and what benefits such system gives?
Is it to adress the remote possibility that the bridle wraps around the PC and thus preventing it from inflating?

[TomAiello 25]

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Is it to adress the remote possibility that the bridle wraps around the PC and thus preventing it from inflating?

Yes.

Regardless of how remote the possibility is, bridle/PC entanglement did kill a leading BASE jumper (see #69, on the List), and we would be foolish not to take a hint from that and try to minimize the chances of it happening again. The more lessons we learn from each accident (for example, the floating handle from that accident), the less chance we'll have to experience them again.

Personally, I know 3 cases of this occuring (one is on the list, one cleared after a hesitation, and one landed with a full knot in the bridle). I am absolutely certain there are many more. If we can avoid this problem, I think we ought to.

-- Tom Aiello

[email protected]
SnakeRiverBASE.com

[lifewithoutanet 0]

The more thought that I put into this, the more I stand by the fact that it's adding an additional point of hang-up potential. That it's worked well so far doesn't ensure it will continue to. I'm not sure the benefit really outweighs the risks.

-C.

[lifewithoutanet 0]

Do you have any knowledge about how the PC was packed in each of these cases?
-C.

[TomAiello 25]

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Do you have any knowledge about how the PC was packed in each of these cases?

Yes. And also about the construction of the PC.

I don't think there's a silver bullet here. I do think that there are lots of incremental improvements to be made in PC deployment and inflation.

-- Tom Aiello

[email protected]
SnakeRiverBASE.com

[lifewithoutanet 0]

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Yes. And also about the construction of the PC.

This information would be interesting to hear, if and when you have some time to elaborate.

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I don't think there's a silver bullet here. I do think that there are lots of incremental improvements to be made in PC deployment and inflation.

Nor do I. I'm just wondering if this has come far enough to field it. I've Emailed Morpheus and a couple of other manufacturers to get their take on it, as well.

-C.

[TomAiello 25]

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When pitched using such an internal BOC stow, the pitch of the PC will only extend the bridle to just beyond the arm-length of the jumper...

Collin,

Is this from a test that you did?

When I played with the Morpheus system last year, practice pitches (on the ground) got the PC all the way to bridle stretch.

-- Tom Aiello

[email protected]
SnakeRiverBASE.com

[lifewithoutanet 0]

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Is this from a test that you did?

No, it's from theory, just sitting around thinking about it.

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When I played with the Morpheus system last year, practice pitches (on the ground) got the PC all the way to bridle stretch.

In which case you're missing a factor of relative wind, which will grab the PC as it leaves the jumper's hand and have an effect on how far it is able to extend outward from the throw, before being pulled up and above the jumper. Again, this will vary by the delay taken.

At the time I first posted, I wasn't sure who was offering this, or exactly how it was constructed (what material was used in the sleeve, for example, how tight the corners were, etc.). Now that I've seen pics of Morpheus' design, I can think about it a little more. I wonder if making the mouth of the sleeve broader than the rest of the sleeve would help eliminate snag potential on the corners.

-C.

[yuri_base 1]

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The more thought that I put into this, the more I stand by the fact that it's adding an additional point of hang-up potential. That it's worked well so far doesn't ensure it will continue to. I'm not sure the benefit really outweighs the risks.

Exactly. Both chances are small, but who knows what exactly they are. If, for example, the chance of bridle wrapping around PC is 0.05% and the chance of bridle hang-up in the pocket is 0.5% (both - hypothetical figures), then this bridle pocket is nothing but safety hazzard. Is it possible to measure these figures? I doubt any manufacturer would do thousands of test PC throws in wind tunnel just to determine these probabilities. Unfortunately, some things are impossible to predict until The List claims another test jumper...

If you ask me, anything that keeps bridle on the container when you throw, instead of providing a clean PC-to-pin path, looks scary. I noticed in Keen n' Able in the opening scene (Miles' 1000th jump) that he didn't tuck the bridle under the side flap. Asked Shane why and he said that's to decrease the chance of bridle hang-up on the bottom of container in case of gainer overrotation. Clean path = good, all kinds of contraptions between PC and pin = bad.

Yuri

Android+Wear/iOS/Windows apps:
L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP
iOS only: L/D Magic
Windows only: WS Studio

[lifewithoutanet 0]

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I doubt any manufacturer would do thousands of test PC throws in wind tunnel just to determine these probabilities.

Yes, but I doubt any manufacturer would recklessly field an option they haven't tested. This thread was intended to spur debate, which it has, and get people thinking about potential snag-points. It was not intended to paint someone as irresponsible. I'm not saying that that's what you're saying, Yuri. I'm just making it clear that despite my feelings on the design, that's not my point.

-C.

[helge 0]

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Personally, I know 3 cases of this occuring (one is on the list, one cleared after a hesitation, and one landed with a full knot in the bridle). I am absolutely certain there are many more. If we can avoid this problem, I think we ought to.

Are all theese 3 cases WS jumps?

[TomAiello 25]

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...see #69, on the List...

I meant #70 (Lukas Knutsson), as several people had pointed out to me.

Interestingly, I got the number by pulling up www.BASEFatalities.com, which I thought was just a mirror of Nick's site, but which appears to be an out of date copy of the information, with a different set of numbers.

-- Tom Aiello

[email protected]
SnakeRiverBASE.com

[TomAiello 25]

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Personally, I know 3 cases of this occuring (one is on the list, one cleared after a hesitation, and one landed with a full knot in the bridle). I am absolutely certain there are many more. If we can avoid this problem, I think we ought to.

Are all theese 3 cases WS jumps?

No. Only one of them was WS.

The knot in bridle case was an over-rotated aerial (interesting that it's the same case in which Yuri_BASE is saying this system might be undesirable) in which the pitch was made in a downward direction, and the PC ended up floating back up through a flailing wad of bridle.

-- Tom Aiello

[email protected]
SnakeRiverBASE.com