Soft Links and Excess Brake Line Stowage

[parachutist 1]

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Flight Concepts - with large ugly knots

These are the ones that I use... the knots are smaller than the barb used on any other soft link I've seen (such as metal rings or PD's fabric patch). It would be very difficult to catch a brake line on one of these knots.

There was a prototype version of Flight Concept's link that was made out of dacron, so the knot on this link was large for obvious reasons, however, the set of these links that I use is constructed from 1000 lb spectra and therefore the knot is relatively small. Honestly I think you'd have to make a concerted effort to get a brake line to catch on these soft links. Maybe you have a set of the original dacron links?

My freefall rig is at the DZ, but I'll take some pictures of the soft link setup this weekend to illustrate just how difficult it would be to catch a brake line on it & I'll post links to those pics here.

Chris

[geronimo 1]

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The excess line they are discussing is on rigs where the excess is passed through the opening on the end of the riser (the space where the Slink tab lives) then looped around the nose of the toggle before stowing the toggle.

How about stowing the excess through the loop of the slink itself (no slink cover of course) before looping around the nose of the toggle before stowing the toggle. I think this does not allow the failure mode described. It has worked for ~80 jumps for me.

A friend of mine stowed her brake line thru the slink. I'm not sure where the loop was routed. She had a hang up about a month ago. Cutaway & pulled reserve. It hung up again last Friday. She tried to get that snag undone. She couldn't get it undone. She could have landed ok with the hung brake line, but I guess she got distracted and didn't stop her downward spiral before reaching the ground.

I have no idea were that practice of stowing the excess brake line thru a connecter link (whatever type) came from. I think it is a pretty dumb idea. But what do I know.
.

---
I have a dream that my posts will one day will not be judged by the color of the fonts or settings in a Profile but by the content.
Geronimo_AT_http://ParachuteHistory.com

[realwildone2 0]

Here is a solution that I use for excess brake line stowage. I use a small stowband cut in half (makes two) and loop it through the brake line metal guide ring on the riser then again through itself. Forms a small loop that can hold excess brakeline "s" folded about two inches in length until all the excess is "stowed". Works like a charm. I have 300+ jumps in this configuration with no snags or steering issues. The brakes unstow easily and steering is normal without interference. The bulk from microline is minimal and the risers pack away just as easily. I don't like the idea of putting the excess line through the riser where the slinks are, that's trouble waiting! Give it a try.

[Hooknswoop 19]

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Here is a solution that I use for excess brake line stowage. I use a small stowband cut in half (makes two) and loop it through the brake line metal guide ring on the riser then again through itself. Forms a small loop that can hold excess brakeline "s" folded about two inches in length until all the excess is "stowed".

Great solution!

Derek

[grasshopper 0]

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I have no idea were that practice of stowing the excess brake line thru a connector link (whatever type) came from. I think it is a pretty dumb idea. But what do I know.

jumpshack (they make racers) show that in their owners manual for the proper way to stow the excess on reserves. but then again, the company has a history of doing unothorodox things, so I won't say I agree with all their recommendations. I mean, rubber bands on a reserve? come on, like safety stows don't work?

anyway, I see nothing wrong with this method of stowing excess brake line if, and only if, you have hard links. but, I'm not a rigger or instructor, so what do I know?

________________________________________________________
Abbie drove me to Idaho and all I got was this lousy sigline

[fundgh 0]

Are you cutting it in half length wise? Sounds a bit confusing, is there a better way to explain what you are doing?

...FUN FOR ALL!

[realwildone2 0]

yes. cut it in half lengthwise where one small rubber band creates two. Scissors work great for this (good ones). You can make a bunch and keep them with your spare stuff. Put one of the bands through the guide ring about half way and loop it through itself. Pull it tight just like a stow band on the "d" bag. Then "s" fold the excess line into about two inch lengths and wrap the rubber band loop around it. Holds the excess like a charm. Good luck.

[parachutist 1]

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Flight Concepts - with large ugly knots

Riggerrob,

Here are some pictures of the final version of Flight Concepts' soft link. It's very unlikely for this streamlined shape to catch lines: The knot system forms an upside-down cone that will shed a vast majority of potential line snags. I've been using this setup with my Xaos-27 for the last 100 jumps with no problems. After the first jump these soft links were set in their proper positions with the knot inside the riser so that there was no need for tacking them in place.

overview of riser setup, fully assembled:
http://www.funjump.com/FCI_softlink/DSC00180.jpg

closeup of soft link setup, fully assembled:
http://www.funjump.com/FCI_softlink/DSC00181.jpg

soft link rotated 90 degrees to show knot system:
http://www.funjump.com/FCI_softlink/DSC00183.jpg

same as above, with a dime added for size perspective:
http://www.funjump.com/FCI_softlink/DSC00184.jpg

soft link disassembly:
http://www.funjump.com/FCI_softlink/DSC00185.jpg

Chris Warnock

[ZigZag 0]

if not for the small knot.
Comparing the last two jpg's one might get a little scared, seeing this little knot holding the entire assembly together, and considering what my life might be worth, I'd like to see a somewhat larger "catch-knot", as improper construction of the loop-end (size of loop) could easily let the knot slip through. In your case it looks good, but remember that other folks out there with less understanding of the dynamics and physics involved might be tempted
to copy your design, with disastrous results. Beware of folks that would like to re-engineer your design.

The mfg's that have so far emulated the old design of the "dacron" soft-links that have been finger-trapped into themselves and then bar-tacked at the running ends have at least incorporated a large catch
that the loop is "thrown over". In your case, I honestly believe that you are exposing yourself to a higher risk factor, altough you have proven that you understand the design of soft-links. Reconsider your design!!!
Ziggy

[parachutist 1]

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I'd like to see a somewhat larger "catch-knot", as improper construction of the loop-end (size of loop) could easily let the knot slip through

Hi Ziggy
The loop end is basically a lark's head, and so it'll cinch itself as tightly as possible against the knot. When it does this, the Spectra sets... so that the Lark's head does not loosen without some serious pulling. If you could PM me a snail mail address, I'll send you an example to play with.

thanks,
Chris

[ZigZag 0]

For the benefit of all, yes, the loop does cinch and set itself around the knot, but it is also prone to
loosening itself, unlikely, but nevertheless possible, much as in the case with finger-trapped lines. A fingertrap holds quite well under tension, as the loop does, but one has to be creative and think of possible scenarios were the loop "could" loosen just enough to give the knot a space advantage where it could slip past the loop!!! To elaborate a little further, current soft-links on the market rely on an interlocking action, quite different from the "cinch". So we know that soft-links as we know them, work. But who would have thought that the interaction of stowing excess brakelines in the overfold of the top end of risers could cause a malfunction. Well, our knowledge base is not that poor. We have, or some of us have, plenty of experiences with various configurations of excess brakeline stowage. Consider
the reason for large plastic washers that where installed on some risers, actually slipped onto the rapide links, only to prevent the slider grommets from trapping thick dacron lines and the subsequent use of the control lines, which would have been pinched off. There is documentation of brake to toggle lines that have wrapped around the toggle and guide rings!!! There are good reasons for Velcro
configurations, or other sane methods to stow the excess brakeline. None of them are perfect, but have withstood some testing over a time period.
Much of the problems can be traced back to inadequate maintence, worn Velcro( or hook and pile fastener if one prefers), worn keepers, etc.etc.
In the quest to reduce maintenace, we all to often come up with "innovative" solutions, that in the end might cost someones life. No, none of us can prevent all fatalities that are born out of innovation, or else the Space Shuttle would never have flown, but we do need to be somewhat more "patient" with our personal innovations and think things through!!!

There may be good reason for some of the "old" school of thought yet.
Ziggy

[parachutist 1]

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For the benefit of all, yes, the loop does cinch and set itself around the knot, but it is also prone to
loosening itself, unlikely, but nevertheless possible, much as in the case with finger-trapped lines.

Similar to other removeable soft links, the only time that this setup would be prone to coming apart would be after installing it, before the first jump. This risk is eliminated as soon as you grab the line group in one hand and the riser in the other and pull (Part of the installation procedure for any soft link). This adds enough pressure to set everything in place. It's not going to come apart if it has been installed correctly.

This soft link setup does not need to be monitored any more than any other system. I would check it after the first jump to make sure that everything has been set properly, as I would with other soft link, but that is the extent of my concern for their installation.

I still think you'd look at this setup differently if you had one in your hands, and I have an envelope here with your name on it
Chris

[chemacelorio 0]

The best thing that I can recommend everyone is to be aware of the potential problem with soft links. My toggle got stuck after a big way (it happened to be in Perris two days after the incident) and I believe that because I have heard rumors about a potential problem with soft links I was able to recognize it and have a safe descent to the ground, I was in Eloy back in April when a fatal incident occurred, I heard from eye witness that a girl started spiraling hard towards the ground and a couple of days later someone told me that it might have been related to the soft links (bear in mind that this is back in April). As soon as my right toggle got stuck the first thing that came into mind was "Eloy", I calmed down, conpensanted the turn (since the other break was released already) and easily unhooked the excess brake line. The biggest problem I see, after the experience that i had, was not so much that the excess line got stuck but that it felt like if pulling on the toggle harder would unsnapped it, it really felt that way and our minds have been trained for hundreds or thousands of jumps that pulling that yellow thing down releases the break. In my case the excess line got stock with the knot of the front riser slink, so pulling on the toggle applied pressure to both risers on the same side and thus creating a hard turn.

To summarize, until the manufacturers come with a definite solution recognizing the problem can save your life. Keep in mind that pulling on the toggle hard will create a large problem from a smaller one. Hiding the slink knot in the risers and stowing the excess line can also prevent the problem, that that has been discussed in this thread already.

safe landings,
Chema

[Samurai136 0]

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In my case the excess line got stock with the knot of the front riser slink, so pulling on the toggle applied pressure to both risers on the same side and thus creating a hard turn.

bold face my emphasis

So it sounds to me that you do not have the 'knot' / 'tab' of the slink tacked to the riser?

How do you stow your brakes?

Ken

"Buttons aren't toys." - Trillian
Ken

[chemacelorio 0]

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In my case the excess line got stock with the knot of the front riser slink, so pulling on the toggle applied pressure to both risers on the same side and thus creating a hard turn.

bold face my emphasis

So it sounds to me that you do not have the 'knot' / 'tab' of the slink tacked to the riser?
Ken

Well, I do now . It was tacked at some point but I hadn't checked it that weekend, it wasn't on my map before as something to check for. So at the time of the incident my guess is that the knot was completely out of the riser, cause the excess line stuck well to it, keep in mind that with an open canopy the knot has enough pressure to keep it at 90 degrees turned since there it is in tension on the lines.

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How do you stow your brakes?

Ken

Same answer, before i just left them laying around now I am tucking the excess line inside the rubber housing for the breaks themselves, I am unsure if I like this setup or not, among other things because of the extra wear on my break lines.