Line twists -- why now?

[redshift 0]

I know the subject has been recently discussed, but I'll ask again anyway. I think I'm packing my Triathlon pretty consistently, but I got two unpleasant line-twist situations in a row yesterday. So far, the reasons I've heard are:

- bad body position
- not enough free line between risers & d-bag
- different sizes of rubber band stows

For jump #2 yesterday, I had about 14" of free line between risers & d-bag, and I think I was in a good, symmetical position during deployment (but don't remember clearly). Result: 2 line twists. For jump #3, I left about 24" of free line, and was very careful about body position on deployment. Result: 1-1/2 twists.

I hate line twists and would like to prevent them. Any more ideas?

[SkydiveMonkey 0]

If I leave 14 inches on my rig it's 2 twists straight away. I leave at least 2 feet.

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[KevinMcGuire 0]

How many jumps are on the canopy? You may have an issue with your brake lines. Check them to see if they are the same legnth. Also check your P/C to see if it is damaged. Just a thought

[FrogNog 1]

Two line-twist openings in a row may just be chance. I think you should jump a bunch more times just to be sure.

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Pull.

[AggieDave 6]

If nothing is wrong with the equipment, about 95% of all linetwists come from bad body position. By bad I mean not even in the harness when people pitch.

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[hookitt 1]

- bad body position <== always possible
- not enough free line between risers & d-bag - different sizes of rubber band stows <== I Very highly doubt this one.

Do you tuck your risers or lines under the reserve tray or do you put them straight down the sides?


Keep the 2 feet of free lines and be sure to put the line/risers straight down the sides and not under the reserve tray.

Be sure the final stow is not overly tight.

Besure the d-bag goes into the main tray symetrically.

If it's only 2 times so far, I wouldn't be too concerned. Take a good look at how you place the bag into the container, and be certain of the condition of the Pilot chute. Ask Clay about it.

Unfortunately I will be away from Bay Area for at least the next couple weeks. When I'm back, bug me any time. If you're wondering who I am, PM me and I'll send you a picture. I look just like that guy

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

[jdthomas 0]

Line twist could be an endless guess on how and why, canopy to old, out of trim. the way the lines are stowed, length of lines, pilotchute could be old and the kill line has shrunk to make it pull funny, the old body position.. the list goes on and on man..
Try packing your friends canopy, see what happens.. just do a process of elimination and when all else fails.. just forget about it and just accept it as a new adventure each time you deploy.

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[SkydiveNFlorida 0]

Usually if I have a nice stable position on deploy, I have no problems. When I wave off and reach, I hold for a second there to stabilize before I pull. My boyfriend told me to do this and is helped me so much.

That said, sometimes I do pack like shit and have problems, too. I had the pleasure of being in a group discussion of sorts with Brian Germain this past weekend, and someone asked about uncontrollable openings, or turns on opening. Anyhow, his reply threw me for a loop. He said that during testing they'd found that having the locking stows tight, but all others stows not as tight, gave the best openings. He said that you want the bag to deploy nice and straight, and then, ideally, at the end to pause before the locking stows come out. Obviously, this is not word for word, he spoke with much more experience and worded this better. But, i'd always been taught that the locking stows should only wrap once, and all other stows twice. This went against everything I was taught. So, last jump of the day, I did it this way. And, whaddya know, nice on heading opening:D Whatta guy! And, bonus... Now I don't have to double band everything. haha.

Oh, I forgot to mention, I asked about bag lock if double stowing the locking stows, and he said that it was best to use the smaller rubber bands instead.

Angela.

[redshift 0]

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Do you tuck your risers or lines under the reserve tray or do you put them straight down the sides?

Down the sides.

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Be sure the final stow is not overly tight.

I use small bands on my bag, single-wrapping the first two (center) bands, then double-wrapping the outers, because they're always a lot looser for some reason. Maybe I'm packing so that the main is fat in the middle and making the bands in the middle tighter?

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pilotchute could be old and the kill line has shrunk to make it pull funny

It's a somewhat small pilot chute; 23" for a 190 Triathlon.

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How many jumps are on the canopy?

Lots.

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You may have an issue with your brake lines. Check them to see if they are the same legnth

I'll do that, but don't know why that would cause line twists.

[hookitt 1]

23" is way to small. I suggest replacing it with a 28" to 30" pilot chute.

Take a look at your lines next time and notice they are cascaded, which means another line branches out. There are more lines where the cascaeded lines begin. That will explain why the stows looser as you continue on toward the risers. Line twists generally occur, prior to the d-bag coming off the canopy. Is that what's happening?

Start with going upstairs and talking to Bonnie about replacing that pilot chute.

By the way, how many jumps is "lots"? How my jumps on the line kit?

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

[PD126r 0]

IMHO rubber bands might be a considerable contributor to line twist. But what's left out in this thread is the importance of symmetric stowing.
You need equal amounts of stows on both sides of the bag in order to get the bag bouncing back _and_ forth equal amount of times before line strech. More bands on one side, and the bag ends up off-heading when the canopy goes out of the bag; the lines will already be crossed, and the line twist can begin...

BTW: _How_ can a small PC contribute to line twist? Not enough speed/stability compared to a larger one? Anyone??

[hookitt 1]

Yes you are correct about the pilot chute.

The Pilot chute needs to be an anchor. A 23" pc has much less drag there fore is not as good of an anchor. This is more of an issue if it's worn and slowly pulls the bag out. If it takes it from the back slowly, the line twists can happen as soon a the bag comes out of the pack tray and sits briefly just above the jumper.

If the Pilot chute is asymetrical, it will orbit and can also help cause an off heading.

I'll add this as well. I agree that the stows should be symetrical *but* I've done so many rubber band experiments and find it much less of a factor than anything else. If the first stow closest to the riser is tight, and the Pilot chute is small, then it can create problems, especially if the rubber bands are on the sides of the bag rather than on the flap.

That is the exact configuration as described by the original poster..

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

[Luv2Fall 0]

What's the "average" useful life of a F111 pilot chute......particuarly the non-callospable type? Thanks.

[redshift 0]

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23" is way to small. I suggest replacing it with a 28" to 30" pilot chute.

Sounds right.

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Take a look at your lines next time and notice they are cascaded, which means another line branches out. There are more lines where the cascaeded lines begin. That will explain why the stows looser as you continue on toward the risers.

Ok, that's obvious (now that you've pointed it out!)

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Line twists generally occur, prior to the d-bag coming off the canopy. Is that what's happening?

I have no idea, I don't look up that soon, since I'm wanting to stay in a flat, symmetrical position until inflation begins.

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By the way, how many jumps is "lots"? How my jumps on the line kit?

On the main, I don't actually know. At least 500, I'd say, maybe more. Clay's checked out the main and the lines (etc) and figured both are about halfway to replacement.

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But what's left out in this thread is the importance of symmetric stowing.

I don't use the very last stow, there's not enough line.

For you d-bag designers out there... this all makes me wonder if having two sets of stows, one on the left for the left set of lines, another on the right for the right set, would help solve this problem, the theory being that the bag, being under tension at both ends simultaneously (instead of alternately) would tend to stay oriented correctly.

[livnbored 0]

Everything being described sounds more like your linetwist problem is as everyone is stating... a trial and error thing. All canopies have a bit of character, and it takes awhile to learn their little nuances. Your pilot chute does sound very small to be dragging that triathlon 190 out, but I'm gonna have to guess it came with your rig. You appear to be a fairly new jumper, which may also give a little sway to the idea that you are not dumping stable, but that will always be the first thing that anyone will say in response to line twists.
About your line stows... I'd listen to what everyone is saying. 14" does sound too small. Which leaves the question of your risers which was earlier stated, sort of. You do want your bag to come clean off your back when you deploy. Meaning no line stows should be releasing until the risers have cleared your shoulders. Any jerking of the bag at this point and it's linetwist city baby. How you place your risers and your bag in the container does matter a lot more than symmetrical line stows and even rubber bands. Mind you, as the bag rocks to release your line stows, you don't want it doing some rock and roll dance, but again, this is just my opinion. Be more aware of how you want everything to leave your back when placing everything in your container. Straight risers, no hang ups.