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wildernessmedic

Consistent line twists

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How am I supposed to do both? If I make the line stows shorter I end up with more leftovers at the end.



Do an extra stow? Most bags will allow you to put an extra rubber band here and there.

Edit: not leaving enough excess between risers and first stow can also cause line twists. Note that as the bag rolls into the container, the lines get more stretched and it's fairly common that the lines will get trapped under the reserve corners under tension, which will easily spin your bag. Make sure you leave enough excess according to the rig instructions. Since I don't have a ruler on me, I estimate mine using one and half to two full stretched hands.

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Good on you for checking the PC with your rigger. You've probably eliminated that one possible culprit.

Now on to the rest we've listed in this thread:
Get someone else to pack for you.
Get video of your opening to look at body position and what happens to the container.
Read the manual for your container to be sure you pack it correctly.
Have your kill line checked.
Check your line lengths.
Have a rigger watch you pack.

How about: pack and jump another rig and see how openings are.

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wildernessmedic


PC is old, but rigger says its still fine, same with kill line.



That's good, especially about the kill line.

Still, riggers don't have portable wind tunnels or Pilot Chute Gauges, so one can't always predict whether a pilot chute will have issues in the air. We might only be able to say, "It looks kind of older... probably will be fine. But if you're having problems, maybe not."

So the rigger may only have eliminated any blatant pilot chute issues from being the culprit.

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That was simple. Not sure why I didn't think to throw an extra stow in.

sammielu

Good on you for checking the PC with your rigger. You've probably eliminated that one possible culprit.

Now on to the rest we've listed in this thread:
Get someone else to pack for you.
Get video of your opening to look at body position and what happens to the container.
Read the manual for your container to be sure you pack it correctly.
Have your kill line checked.
Check your line lengths.
Have a rigger watch you pack.

How about: pack and jump another rig and see how openings are.



Had other people pack. Same issue.
Packed according to manual, although I've altered some to see if it helps here and there.
Had a rigger watch me pack.
Kill line checked.


Hard to get video of it opening because sometimes it happens, sometimes not. I may end up needing someone to film me for 5-10 jumps. Or it may twist 4 jumps in a row.


I think I'm just going to get a new PC just to take that out of the equation.

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wildernessmedic

So this is still an issue. It seems to be spinning once the D bag comes out.



Can you clarify if the line twists are formed before the canopy comes out of the DBag (ie. on the way to line stretch) or after line stretch when the canopy is out of the DBag. Maybe I missed the answer to this but it would help isolate your problem.

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ChrisHoward

***So this is still an issue. It seems to be spinning once the D bag comes out.



Can you clarify if the line twists are formed before the canopy comes out of the DBag (ie. on the way to line stretch) or after line stretch when the canopy is out of the DBag. Maybe I missed the answer to this but it would help isolate your problem.

I meant spinning between extraction from the container and canopy extraction from D bag.

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Is that d-bag in the photo a good fit for the container? Have you tried simulating a deployment to see if the bag is catching on the sideflaps making it rotate?

With the container fully closed, stand on a chair and pull on the bridle to pull the pin and lift the d-bag, and see if it comes out straight, or maybe one corner comes out first, or there is some resistance from the flaps. Give it a bunch of tries and see if you can spot something.

If you can borrow somebody's bag/pc for a couple of jumps it would be a good idea to definitely discount the PC. Did you compare the lenght of the support tapes on it to make sure it's round and symetrical?

ETA: https://www.youtube.com/watch?v=auIexsbmmEo

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What kind of 190 is it? and how old are the lines? Why do you think the bag is spinning before line stretch? There is no real way for you to know this.

Earlier you stated this:

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It seems to open and then toss me around like a rag doll or spin me.



Which makes me ask two things. Does the harness fit you well? You state that you bought the rig from your instructor. It may be that you compromised on a good fit because the rig was available. And the whole "body position" thing. It gets blames for a lot of things and is poorly understood.

DO NOT let your canopy "toss me around like a rag doll". When that happens you lose control of your body position and often your harness will load on one side before the other. Especially if it fits poorly. That will instantly start your canopy turning before it fully opens. That's what line twists are.

Instead, when you feel your canopy get to line stretch and stand you up push both your legs straight down and evenly toward the planet. Try to keep your hips even and try to keep even weight on both sides of your legstraps. Then you will be steering it straight instead of just letting it go off the road and into the ditch! Begin flying your canopy as soon as it is exposed to the air. Don't wait for it to decide on it's own where to go!
Always remember the brave children who died defending your right to bear arms. Freedom is not free.

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Possibly not a good fit into the container. I'll have my rigger look closer at it, but it definitely has to be pushed into the container to get it in. Fair amount of pressure on the side flaps.

Specter 190. From what I've heard it's supposed to be one of the most on heading soft opening canopies.

The harness is not a great fit, but it's alright. The hip/leg attachment rides a bit high up my side.

Not sure why I said it tosses me like a rag doll, I think that was a while back. But I probably meant once it inflates I spin. It commonly changes heading rapidly while inflating. Sometimes as much as 90 right, 90 left, then 180.

I'm going to check the lineset tomorrow. Talked to the person I purchased it from, and it sounds like it's about due for a new set even if it is still trimmed.


I mentioned it spinning during line stretch because I positive it was packed straight. So some time between coming out of the container and the canopy extracting from the D bag it must be getting spun. I've looked up pretty early on a few jumps and seen it spun up before the canopy has really even started to inflate.

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wildernessmedic

But I probably meant once it inflates I spin. It commonly changes heading rapidly while inflating. Sometimes as much as 90 right, 90 left, then 180.


This makes it sound like it happens after line stretch.

wildernessmedic

I've looked up pretty early on a few jumps and seen it spun up before the canopy has really even started to inflate.


This makes it sound like it happens before line stretch.

Which one is it? Or is it both? Is there ever a noticeable hesitation in the extraction process?

If it is spinning on the way to linestretch you need to start out by doing some research. You need to find out what size canopy is meant to be in that container. You said earlier that you were unsure. You also said that it is a tight fit. Over stuffed containers can easily cause line twists to form as the bag is extracted from the container. You also need to find out the correct size PC for your rig, especially if it is 2nd hand. Incorrectly sized PCs are problematic. And as others mentioned, PC condition.
If it is happening after linestretch then as others have said it could be something wrong with the canopy. Check the trims and if 2nd hand I would double check the slider size. People do weird stuff sometimes.

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I'd have a rigger pack it or watch you pack it. I had a similar problem and it turned out that I was giving myself a 1/2 twist on packing, I thought that I had been doing it right but alas I wasn't. Yes it was dumb but it was simple fix and now I have no more line twists. I was simply putting the dbag in with a 1/2 twist. Not sure if that is your problem or not but I'm just speaking from my own experience.

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ChrisHoward




Which one is it? Or is it both? Is there ever a noticeable hesitation in the extraction process?



The first one is without line twists. It just surges around a lot sometimes. Not too worried with that one.



It's hard to say about hesitation. First instinct is yes, but I've been playing around with my pack jobs for slower/faster openings.

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So some time between coming out of the container and the canopy extracting from the D bag it must be getting spun.




Probably not. But if so your pilot chute may be either too small or too worn out. What percentage of jumps have line twists and when you get them how many turns do you get?

I'm going back to what I told you earlier. Stab your legs straight down and do your best to load the harness evenly. A lot of people have fixed this problem in this way before.
Always remember the brave children who died defending your right to bear arms. Freedom is not free.

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i started packing my own kit recently and after 25 goes packed my first line twist.

strangely, when i offered the dbag to the container, i thought to myself, did i twist this?

now this may be self fulfilling but,

i didnt look up at the canopy which im told can cause it to rotate if you arent symetrical, and i also noticed that i hadnt left a lot of line between the bag and the risers (i was told about a metre and this was half that)

i've packed the same again so i'll let you know if the short remaining lines might be the cause.

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I think the last 8/10 jumps.

I did one this morning like you suggested, still have a full 1 1/2 twist.

When I said I looked up, thats not usual. I just got curious and wanted to see if I could catch it a few times. I guess it doesn't make too much sense to look since it can cause it to twist from looking anyway.:S


I left my rig with friends while I'm gone for a month. Rigger is going to check line set, and friends are going to put a few jumps on it to see if it happens to them.

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