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I admittedly don't know a lot of BASE history, so if I'm totally ignorant to some tried & discredited tech, I apologize.

Anyhow, I'm picturing having a VERY flexible but incompressible hard housing that contains the control line extending up from the rear riser to a point below the control line cascade (such that in a full flare the cascade would be above the end of the housing).

Providing the hard housing was flexible enough, packing would be the same, but in the event of line twist, the hard housing would prevent the control line from being "pinched" and you would be able to steer your canopy even in the throes of heavy line twist.

Just a thought...

not sure if I understand what you mean, but don't think it would work like you're thinking.

in a line twist, that housing is going to be twisted along with the other lines, and even if the control lines are running through it freely, they will be creating their own friction on the housing from the twists.

Take some metal housing(very flexible and not compressible) from a skydive rig and wrap it up quite a few times, notice how you can pull it but it doesn't retract very easily, imagine that the length of what you're talking about.

somebody correct me if I'm wrong...

There are certainly materials and liners that would have a low enough static friction coefficient to not bind up amidst line twist. My main concern would be that the rigidity of the hard housing would push the line twist up towards the canopy.

Let's pretend it is easily do-able...

What is the cost benefit analysis?

Extra weight and complexity to deal
with a rare occurance, that is still
very dealable with our existing
methods.

In 300 BASE jumps I have had my
lines twist exactly twice (3 x 180's)
and toggles are not always the only
answer to a shitty situation...

Thinking is good, I believe it makes
you pack better, read the winds with
a keener eye, and usually respond
a little better to those inevitable shit
sandwiches that BASE serves up now
and then however, look at what the
swoopers jump, the CRW guys jump,
the hardcore active BASE guys jump.

Your solution would probably cause
more problems than it hoped to fix.
But keep reading and thinking

I've had the same idea and think if it was designed properly it'd help. These people who say it doesn't happen often enough to worry about...do you pack with a tailgate or just wing it because it doesn't fail often enough?

How would you stow the lines in the tail pocket?

Did you change subjects? Im not sure that a tail gate, or lack of, contibutes to line twist.

What if the twist is up high? Above the housings?

I haven't been in the sport for too long, but most line twists seem to be below the steering cascades, but I certainly can't say it's a rule or more common.

Housings would be be stowed in the tailpocket just as the control lines are currently stowed.

It actually seems do-able at first, but when you think about it,

1. LRM would be impossible if the housing is attached to the riser.

2. Slider up will be impossible since the guide ring will be interfering with the housing if the housing is "floating''

3. If you somehow manage to make a design where the housing stops short of about 1.5m from the upper cascade to allow brake input, the whole point of it is lost.

4. It will be impossible to untwist the brake lines while packing.

5. The HUGE snag potential of the upper end of the housing to the slider. Imagine the slider going down,
and it is suddenly stopped by the ends of the housings.

6. Routing the control lines through them would be a pain in the ass.

A thought I had was having the housing "loose" on the line, such that when the toggles were unstowed, the housing actually moved freely with the line, even sliding down the control line to the toggle due to gravity's effect. However, in the even of a line twist, the housing would remain in place in the twist due to frictional forces acting on the exterior of the housing. Essentially it would be a "there when you need it, not when you don't" kind of system in a SD application.


The housing could be affixed to the riser for SU applications, or simply have a sufficiently large OD to prevent it from entering the control line. Having a conical bottom would allow centering in the control ring.


Again, this comes down to WHERE the twist occurs. Admittedly this is the largest fault of the suggestion. If the twists occur above the upper end of the hard housing, the whole idea is naught. In most stills and videos I've seen of light to moderate line twist, and one instance of LT at Perrine I've incurred following a Poppins, the top of the twist seemed to be well below where I predict a full flare would have brought the cascades to (which is where the top of the housing would be)


Avoidable. And if you need to stash and dash or for some reason don't stow your toggles upon landing, then it's not THAT hard to remove the toggle.

Initial installation could be done with stiff wire drawing through the housing, subsequent removal and installation could be performed by means of tying thin string to the end of the control line, removing housing, leave string in housing, and then removing string from control line. It wouldn't take much more time than removing the toggles does now.



I picture a stiff, conical "seal" at the upper end of the housing. The OD of the cone's top would be very close to the OD of the control line, while the OD of the cone's bottom would be smooth and flush to the OD of the housing. Making the cone "taller" would decrease the "dr" or rate of of diametrical change (sorry for the calculus reference)


As I stated in my initial post, the housing's upper surface would need to be sufficiently low to allow a full brake input. This was also discussed in line item 3 in this post.

Well then it actually is doable
Still, I don't believe it will make past the prototype phase.
And sorry for my last two line, misunderstood the original post a lil

Or at least worth further exploration...


It's unlikely that I will be prototyping anything soon. I am confident in my basic engineering/mechanics, but certainly don't have the parachutal experience or time in sport required to examine making major design changes to such equipment. I'd be interested in seeing the discussion go further, though.