Line twists after your under a good canopy

[SurfFlite 0]

Just thought I would post a problem that I experienced last Saturday at Eloy. I'm posting this because I had never heard, seen or thought this could happen. I was coming in for a landing and at ~1500ft I realized I was going a little long. So I decided to make a 360 turn to bleed off some altitude. About 270 degrees into the turn my main twisted up on me. (Safire 149 loaded at 1:3 to 1) It spun up about 4-5 twist and bunched up my slider. I figured I was at around 1000ft when this happened and all I could do was watch it twist and hope it stopped soon. I never looked down, just up at the mess. I kicked out of the twists (from witnesses at around 400 feet) and made an uneventful landing.
What happened? Well my turn was a toggle turn (no riser) I had done this quite a few times with no problem. I'll NEVER do it again. I was jumping with Omar on that jump and he sat me down and lectured me about why you cannot use toggles only to turn. He said that he had only seen this happen 1 other time in his skydiving career. I feel very lucky to be able to post this. Had the twist collapsed one end of my canopy I would proabaly not be here today.
I have studied so many skydiving videos and attended lots of senminars and talked to so many great skydivers but not once have I heard that line twists can occur "after" you are under a good canopy. Hopefully this post will enlighten others so it won't happen to you.
Blue skies,
Kerry Vail
Surf Flite-Skysurfing Equipment
http://www.surfflite.com
Edited by SurfFlite on 5/30/01 09:58 AM.

[riggerrob 643]

You can induce line twists in any heavily-loaded canopy by being too aggressive with toggle inputs. This phenomenon has killed several highly experienced skydivers, including my friend Bruce Geikie.
The best cure is education. Go directly to the Australian Parachute Federation's website. Print out a copy of their pamphlet "High Performance Canopies." Read HPC. Start practicing the exercises outlined in the pamphlet. Hopefully a CSPA or Skydive University Coach can help you plan dives and debrief you after landing. Ideally someone will video tape your landings for the de-brief.
Heavily loaded canopies are not inherently dangerous, just intolerant of sloppy flying.

[OmriMon 0]

something like that happend to me 2 weeks ago
i was plying a safire 169 loaded a about 0.75
at about 1000ft i did a 360 to go a little lower duddenly it all collapsed in itself causing me a nasty line twist, a friend of mine that was pretty close got even more scared then i was, i was fighting with the line twist like crazy and it opended after about 4 seconds.
i talked to the dzo later, he told me it caused from hot air that comes from the ground and cold air that comes from above that causes those turbulances that shakes the canopies and collapse them sometimes, it happend to me again later that day but with no line twist and popped back open in a sec
it also happend to another dude this last weekend at my dz under a hornet 190, he was shaking!
Free Skies,
Omri

[Geoff 0]

It's not that rare - It's not so much the high turn rate that causes the twist, but the high angular acceleration. In other words, the canopy turns, but the jumper gets left behind. If you jerk a toggle down, it's easy to twist up with high performance canopies. You can safely turn as fast as you like, but you need to build up the rotation smoothly.
Lowering your slider behind your head and loosening your chest strap should reduce the chance of inducing a twist - you don't say if you'd done either of these. This lets the lines and risers spread a little wider.
Geoff

[SurfFlite 0]

Geoff
My slider was collapsed but not behind my head. My chest strap was not loosened but not that tight either. I was FF'ing so it was somewhat loose.
Kerry Vail
Surf Flite-Skysurfing Equipment
http://www.surfflite.com

[Grogs 0]

Geoff explained it right. I can crank a toggle turn as hard as I want to on my Silhouette (moderately loaded), and nothing much will happen, but if I do a toggle turn, release it, and then begin another hard toggle turn before I've completely recovered, the canopy will spin up on me. On a highly loaded elliptical, you can probably spin it up by just being uneven in the harness when you turn, but I haven't experienced that yet so I can't say.

[gus 1]

I did exactly the same thing once, on a Quadra 170 that can't have been loaded at more than 1:1. Only put a couple of twists in, at about 1500 feet but it scared the living sh*t out of me. This was on about my 30th jump with only a few previous jumps on the Quadra.
I now jump a Spectre 150 and in the 100 odd jumps I've put on it I've never done the same thing and I throw it around as hard as I can. I guess it's a combination of canopy, circumstances and bad luck.
Gus

[adamh 0]

Thanks for the warning - I never new this could happen till I read this.
I'll have to use those front riser loops more when I turn!!!
Adam H

[Lindsey 0]

However....I would hardly call a Safire loaded 1.3 a heavily loaded high performance canopy!

[Chizazz 0]

I had that happen to me a couple days ago. I was at about 1,600 feet and did a 360. Loaded at about 1:1. I must have pulled down on the toggle too quickly because it spun the canopy and put in a couple twists. I dunno if I swung myself up beside it but it also started to collapse and drop until i dropped back down. It was easy to kick the twist out. It was also a pretty windy day. I dunno if that affected it much or not. Not something I'd like to experience again.

[catfishhunter 2]

Don't think it takes a highly loaded canopy to end up with "self induced line twists" I jump a Lazer 295 on a regular basis and I did exactly what others have said. I toggled turned right 90degress then a hard left and twisted that sucker right up at 1500' scared the shiot out of me for about 3 seconds. First thought was WTF did I just do second thought was damn I am gonna have to chop this R@#%^@#% THING AGAIN! Then realxed kicked out of it.

So I don't think it matters what size canopy your flying, if your F'n with your canopy you can expect it to F with you back

MAKE EVERY DAY COUNT
Life is Short and we never know how long we are going to have. We must live life to the fullest EVERY DAY. Everything we do should have a greater purpose.

[Mad47 0]

And even on docile canopy. I induced the line twists on Sabre 170 by aggressive toggle spiraling in one direction and then initiating a turn in the opposite direction before returning to static flight. Stupid ... I had about 30-40 jumps under my belt when it happened. I was terrified when I found myself with twisted up canopy at about 900 ft. Fortunately, it was not spinning and I was able to untwist it quickly. Good lesson.

[FrogNog 1]

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... he sat me down and lectured me about why you cannot use toggles only to turn.

Has anyone addressed that on its face this statement is wrong, misleading, confusing, and/or dangerous?

AFAIK there is nothing inherently bad about turning with toggles. It's just that it can cause certain things, like spinning up a canopy into line twists if done incorrectly. (That part has been covered in this post, for sure. )

If someone had too much altitude and needed to do a 360, I don't think I would tell them it should be a front-riser 360. Surely Omar didn't say this either.

-=-=-=-=-
Pull.

[livendive 8]

Quote

What happened? Well my turn was a toggle turn (no riser) I had done this quite a few times with no problem. I'll NEVER do it again. I was jumping with Omar on that jump and he sat me down and lectured me about why you cannot use toggles only to turn. He said that he had only seen this happen 1 other time in his skydiving career. I feel very lucky to be able to post this. Had the twist collapsed one end of my canopy I would proabaly not be here today.

I'm quite certain you either misunderstood Omar, or haven't paraphrased him very well. From reading above, it sounds like you're saying people shouldn't ever make toggle turns, and that all turns require a combination of toggle and riser input. I'll assume that's not what you meant to say.

FYI to whoever said that it takes a heavy-loaded high-performance canopy to get induced line twists, big parachutes can be spun up pretty easily too, it just takes rapid opposite toggle action and poor harness steering. I've seen a guy induce line twists on like a PD-260 (or so) at about 400 feet by trying to sashay out a little altitude to the right before turning left onto final. He finished kicking out at about 50 feet.

FYI - I've jumped a few smaller canopies that actually seemed tougher to induce line twists on, presumably because of their shorter lines. Of course I might be wrong and have just subconsciously avoided such input when loading upwards of 2.0:1, but they sure felt more "solid".

Blues,
Dave

"I AM A PROFESSIONAL EXTREME ATHLETE!"
(drink Mountain Dew)

[billvon 2,990]

>I was jumping with Omar on that jump and he sat me down and
>lectured me about why you cannot use toggles only to turn.

Of course you can use toggles only to turn. 99% of the skydivers in the world do just that. I do that unless I am a) opening and using the risers, b) setting up a high performance landing or c) playing with a very highly loaded canopy.

[twnsnd 1]

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Had the twist collapsed one end of my canopy I would proabaly not be here today.

It's called a reserve. Feel free to use it.

-We are the Swoophaters. We have travelled back in time to hate on your swoops.-

[DanG 1]

This is why USPA has included reverse turns in the ISP in Category G. It helps teach students what it feels like to over control the canopy, and that control inputs need to be made smoothly. Look through your SIM for advice on doing reverse turns (Category G of the student progression) and then talk to a coach or instructor.

- Dan G

[riddler 0]

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I induced the line twists on Sabre 170

I've done it on a Navigator 190 loaded at 1:1. Premature deployment at 7,000 feet, and I spun a lot to get down before the tandems. Of course, it didn't occur to me to land outside of the peas , but I had very few jumps at the time.

So after doing several 360s in various directions, I managed to induce about 3 line twists at 3,000 feet. I spun 360 in one direction, then before the canopy stopped turning, a very fast 360 in the opposite direction. I think the resulting line twists were induced because I initiated a fast toggle turn on a canopy that was already deformed (from the previous toggle turn).

Trapped on the surface of a sphere. XKCD

[tetra316 0]

I fly a Sabre2 135 loaded at about 1.2. I've done numerous hard 360s with my just toggles up high and followed by a hard 360 in the opposite direction. I didn't know this could cause line twists as I've never even felt like it would wrap up on me doing these turns. Good to know though. I just won't be making anymore hard toggle turns lower.

[Amazon 7]

I have managed to do it on a Conquest loaded at 1.2 to 1.. hard right with full let up on the right toggle and hard pull down on the left to full.. it still continued to turn to the right and dive........WHOA.. now that is a flight characteristic I did not like... it went to 3 line twists.. and dove almost underme as I went back into a fall past it..

LUCKILY I was up at about 3000 ft. and I managed to get out of it. but you can bet your bippy I did not try that maneuver again.

[Zoter 0]

hm.... this is an interesting thread.
I have routinely ( and Im not aware of the correct terminology) rocked/turned my canopy to one side(slightly) to 'load' it with momentum for a fast toggle turn to the other side...
I thought this was a safe thing to do as its a big 'ole 215....
Based on the reports here....even though I have not 'yet ' had a problem......Im educated and will modify my behavoir

Grim Reaper =0.......DZ.com= 1

[Kramer 0]

This happened to a Irish guy (with 75 jumps) that was in Florida a few weeks ago. He initiated a toggle turn at around 1000 feet, the thing twisted up on him, chopped and was under a fully inflated reserve at only 3-4 hundred feet. Pretty scary to watch. Only had an 8 second reserve ride before he landed.

I guess the lesson would be not to do any hard turns under 1000 feet. (Unless you're experienced or swooping or whatever of course) <---- (Correct me if I'm wrong there too).

The FAKE KRAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAMER!!!!!!!!!

[deurich2003 0]

Always keep positive "G"s under canopy and therefore you to stay connected to the canopy! This doesn't mean you can't crank a hard 360 however...it all depends on how you use your toggle. "Snap" turns with the toggle will sometimes leave you with 0 "G"s...this is bad because you are not connected to the canopy anymore e.g. there is slack in the suspension lines. Keep positive "G"s at all times and know where the limit is by practicing up high.

Never Give up! Never Surrender!

[JohnMitchell 16]

[- It's not so much the high turn rate that causes the twist, but the high angular acceleration. In other words, the canopy turns, but the jumper gets left behind. If you jerk a toggle down, it's easy to twist up with high performance canopies. You can safely turn as fast as you like, but you need to build up the rotation smoothly.

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I agree, and from what I've seen, it's most likely to happpen when the canopy is flying slowly, like coming out of brakes, or making S-turns to lose altitude. A friend spun in when he did a hard turn coming out of a stall on a Stiletto 135. When your airspeed is low, treat your canopy like a high performance aircraft, keeping your inputs smooth and inside the performance envelope. Get your airspeed up before make high bank turns. At least, that what works for me, but I'm a pretty conservative canopy pilot. I'm also still here.

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[Extrakt 0]

Just incase anyone wanted the address of the Australian Parachute Federation's website.
It's http://www.apf.asn.au/

Enjoi

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