Basejumper.com - archive

So, I'm curious how rare tension knots are, and I'd also like to launch a new discussion on them.
I saw a friend last spring get a knot amongst a steering line and a d-line (I believe). Luckily the steering line broke and all was well.

From what I've gathered here, possible causes include:
- twisted up steering lines
- poor line tension
- a line dump
- poor stowing
- uneven 5th steering line on older aces and blackjacks
- fluke occurrences

Anybody have additions to that list?
Are either older or newer lines more prone to knots?

Lastly, I saw a old post by 460:
“I wonder if coating the lines with vegetable grade silicone spray would reduce the chance of a tension knot. That type of spray makes the lines very slick. “

Has anybody tried this?

twisted up steering lines coz knots. only tension knot i have had was a steering line on a tandem that the packer didn't untwist steering lines.
take the time and look at your lines

Every case of a tension knot that I'm aware of the configuration, the locking stow (under the tailpocket) was not used.

only tension knot i have had was a steering line on a tandem

Same here!

I fu(ked with it for a minute and then chopped it.

What did you do?

locking stow was not used

Why?

Is there ever a good reason to not use it?

Please explain when time permits, thanks!

I normally use it unless I get in a "experimentation" mode. Only have not used it a couple/few times out of near 400 jumps. I think one was Static Line the other was Slider up.

Other than adding a step (albeit an easy one) I feel it is better to use it...

not to hijack the thread...
on longer canopy rides, many jumpers look up, and untwist their brake lines. packers can get swamped and may not be conducting thorough inspections.

I prefer to simply manage my toggles and NOT letting them twist up... just seat them on the velco after landing.

agreed. I have done a fair share of slider down jumps without the primary stow. never a problem, but I really think it should stay on ll packjobs.

Agreed,

Seriously... take control of your own choices and actions. Sure you pay the packer to pack, but you want them to do it fast so you can get on the next plane. Like you said... open higher one load and un twist your skyrig's steering lines.

I am happy for BASE in that I am totally responsible for my choices and can't BLAME others.

what he said!

- twisted up steering lines:

That does not have real effect on the t-knot unless the lines are ridiculously twisted so much that they are twisted and shrinked when it is not under tension.(that is not realy the case on any pack job)

- poor line tension:

Once the lines are in the tail pocket, lines are not under any tension, so the ''new'' tension is created by extraction..so, poor tension usually does have some effect on smooth opening but it is hard to say that poor tension during packing is the reason for T-knot

- a line dump:

Primary reason for most of the problems on any openings of any type of canopy.

- poor stowing:

99% of stowing are poor!
That leads to conclusion that poor stowing is not the main nor important factor for T-knot

- uneven 5th steering line on older aces and blackjacks :

Bingo!!
Here I would ad..
Any canopies! 5th line can be also even but in combination w long lines and long (deep) cascades and to long ''V''cascades of the steering lines this is the reason of 99% of the T-knot!

- fluke occurrences:

That is what make us all nervous before BASE jump in general....... isn't it?!

See I've been wondering about this. Believe it or not, it wasn't until very recently that the potential for them to get twisted up over time was brought to my attention
But in thinking about it, I couldn't figure why they SHOULD get twisted. Every time I pack, open, and land, I keep the toggles in the same relative position, so... it seems that they ought stay relatively untwisted. I guess I'll check out my old stiletto and find out for sure

why are you so sure that this is a leading cause?

saw many burn demages between stearing cascades and D lines of ALL canopies! Have in mind that those burns were just -self clearing possible T-knot!

fair enough. thanks!

everything I do is my mentors fault.

the freestow tailpocket is asking for trouble (yes, i still use one). ever do any sailing or boating? all those lines wrapped all over each other are asking for trouble. stows would help immensely, using pony tail rubber bands (the small ones used to hold hair) to stow the lines. OR... flaps in the tailpocket to separate each figure 8 line group. a tension knot can be a disaster in base. i have not seen it personally, but i have seen it on video. another potential source of tension knots are twisted brake lines. as you know, they tend to coil on their own entrapping other lines.

460...
yes-the free stow does asking for trouble - same as the jump it self asking for trouble, but surprisingly the free stow works very fine and it is not the problem in it ( works well for over 30 years w no problem. The same goes for canopies it self. They opens even when it is packed in so terrible way...new jumpers...
interesting to know , lighter lines are less chances for T-knot...
Spectra are way less pron to T-knot than dacron...

RE: packing

I have only used 2 people's pack jobs
on BASE jumps, Tom A. during my FJC
and later Paul Wise's when I needed
an extra rig. Both were good!

However watching Paul pack is art!
He uses a protractor and an iron

As for the direct stow, yeah, um I
still don't get why someone would
NOT use it since it is already there
and only takes a second.

As for twisted lines - what?! I always
untwist my lines on every BASE pack
job and most SKY pack jobs.


RE: packers

Usually the only time I have a packer is
when I am doing tandems. Occasionally
I will throw a packer my main on a slow
day as a way to help share the wealth
but I really prefer packing for myself!

Some do the least amount of work required,
like packing a d-bag with 3 different types of
rubberbands and not flaking while others take
pride in their work and are artists! Thanks.


RE: flaps in the tailpocket to separate

I know Nick-Nitro had made some like that.
Has anyone used them? Input? Opinions?

so, has anyone thought about using a hybrid line set?
say Spectra from the cascades up and Dacron from cascades down?

would that improve things from what you have seen?

that won't work... elasticity of this two types are different and would have effect on canopy opening and flying characteristics.

however, i have had a tailpocket line entanglement before that nearly cost me my life. a high speed spinner that i managed to fix about 150 feet from impact, at night, alone, with no cell phone.

the concept of spectra seems like the way to go given how slick the lines are and with the weight advantage, but based on testing years ago by Basic Research, spectra caused terrible off-heading opening due to their lack of elasticity. strangely, i have seen several new canopies that incorporate spectra with few ill effects. it defies me. perhaps the canopy fabric and tapes are different from the past.

the new canopies of the last (I would say) 10 years are much much much more forgiving than previous years. with current canopies, it's pretty much "just get it in the air," but after having experienced multiple malfunctions on a single parachute system years before that, i respectfully disagree with you, Robert, that canopies just have to get in the air.

what's you're reason for using it? just cause it's there?
slider-off, it's not keeping the slider up in case of line dump. I've heard thoughts that it could act as a pivot point just before clearing at slow air speeds. Just so there's no confusion, I've used the primary stow on every jump I've made so far, just saying.


How many twists do you get out of the lines on average? Just so you know, according to my experiences, being less diligent about this is not black death


Hey 460, you ever try that silicon spray?

Also, what if lines were just a little bit stiffer? It seems like a line would be less likely to "loop up" if it were. Any thoughts?

no, but a friend of my master rigger friend did and it worked great. only hear-say so take it (and everything in this forum) with a grain of salt.

Slider-up or slider-off? It had occurred to me that slick lines might lead to some slammer slider-ups.

yes, that's true, based on limited here-say.

RE: primary stow

what's you're reason for using it?

It is meant to stage the deployment,
the goal is to have each step happen
then the next, and that is why I use it.

RE: twists in control lines

How many twists do you get out of the lines on average?

On slider-off pack jobs it depends how
I land and if I had cut a tree down to
get my kit back

On my SKY gear I almost never have
more than 1 or 2 full turns to remove.

I have jumped TM gear that so many
twists that it affect the flight, meaning
I had to give some input on 1 side just
to fly a straight line.


being less diligent about this is not black death

Okay... um, as a low time BASE jumper
I am not ready to start cutting corners
to save myself 2 or 3 minutes on a
pack job that already takes a while.

However, I have raced a guy for the last
slot of the day on a low hop & pop and
heard guys saying they would not jump
the pack job for money (it worked fine).

I do have a bit of packing experience:
2500 mains, 37 reserves, 50 BASE...
in all those I have zero malfunctions
and 1 save.

Plus I have taught a few people how to
pack and their pack jobs are real good
too so my anal-retentive propensities
seem to be serving me well

My DZO puts baby poder on the tandem's lines to prevent tks. Any thoughts on this, anyone else using this method?

i've scene talcum powder used between the flakes of canopies on ejection seats for Russian MIG jets. helps the fabric from sticking to itself given the extremes that these parachutes go through in temperature, humidity, and pressure.

The T/N I had under a tandem set400 was twisted steering lines and I was lucky, a Sharp pull on the toggle cleared it and didn't not have to chop it.
as a tandem master and dealing with a onslaught of new students I took for-granted the packers were checking everything.
Now i take the time to check my lines and set the breaks myself. so far problem solved.
Now I'm into base and have its mentality I see a lot of things i took for-granted in my skydiving years

Just to be honest here, I've never used primary stow under tailpocket on slider off/down jumps...ever...Naturally I do on slider up, reasoning for not doing it on slider off....dunno. creature of habit. Now if my tailpocket got trashed, velcro worn out, etc... and line dump seems much more likely, then I would consider it. Do majority of youse guys use primary stow on slider off jumps now?? GEEZ. Slept through that one.
386

I did a fair share of jumps without doing the primary stow, (slider off of course)
but now I always use it. the reason is I think that without the stow, the canopy could start to inflate on deep slider off delays with normal extraction speed, or on medium/short delays if there is any kind of PC hesitation/extraction hesitation/line stretch hesitation. if the canopy does start to expand and infflate, this could cause line dump (lines getting sucked out on the canopy side of the lines from tailpocket) and would obviously be uneven. this, i think, could easily cause tension knots.

That's what I took from this, and it seems to make a lot of sense.

A well constructed tail pocket in my humble opinion should be enough. I am going to continue to jump slider off without a single stow, especially since most of "our" offs are sub 300'. I'm comfortable with it, and have always considered it to be for slider up anyway...
cheers

You too??

I figured your mom would take full responsibility for not covering proper diet and showing you how to properly work a simple wing suit zipper. my bad.

The "tail Gate" is that what your calling the single stow? and if so on 300' and lower do you still use it?
only have two BD jumps and got wet on the first

no, he is referring to the "secret stow" - the bite of lines you take coming from under the packjob and stow under the tailpocket. Mostly used for slider up jumps to stage the deployment.
the one person in this thread used the phrase "without a single stow" in a sense that he does not use the primary stow (other name for it).

Personally I only use it for slider ups. And if it's an iffy 4sec slider up I opt not to use it. (limited to bridges and good tailwind antennas)
cya

http://www.basejumper.com/articles/

 Another cause i've thought of is not taking a proper delay on a terminal slider up pack job and small pilot chute. Or at least a catalyst for some of the other stated reasons.
Slower deployment-more time for twisted break lines, sloppy line stowage, fluke occurences etc to interfere during the deployment...

http://basejump.pp.fi/images/video/Base/tension%20knot%202004%20Ostankino.avi

theres one for you

FTF !!!

So, does this mean that you wouldn't jump an older blackjack, like one from 2002 until you got this fixed? Im sure the object choice would be one consideration so lets just say for the sake of the question, it is an ideal terminal A with a good tailwind splitting the wide open center of 2 sets of guywires.

Is this the only problem people have seen from the uneven fifth steering line? Is this something that any rigger can easily fix or should I send it back to asylum to be sure its done properly? Thanks

I have two Blackjack 280 s, one older, (2004 before the change) and one new one. In my limited jumps I honestly can't tell any difference.PD would not do the mod...only a complete reline $$.I will probably do it myself this winter.

actually, I believe I told an untruth. I don't believe I've ever really used that locking stow under the tailpocket, cuz just recently when inspecting gear I thought...damn, when did I put that motherfucking band on??!! Now, I do put a few loops of rubber band on the slider itself...guess I'm the only one jumping without locking stow at all. I'm still alive, so fuck yourselves. hah!