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morris

Fast spins (in freefall) after cutting away

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Sounds like a side spin. I was hit hard and went into a violent spin after thirty years of jumping. I could not get out of it and had to pull my reserve, I described it to my friend Bill Morrisey and he said it was a side spin. On my side, feet going forward. Bill did intentional side spin jumps investigating tandem side spin fatality’s Contact Strong Entprise they will send you a video of Bill Morrisey’s test jumps.

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It was for sure not a side spin, I was on my back.
Only similarity being that it also happened after 30 years of jumping. :-)
I have an overall "emergency experience" of about 25 cutaways, some pretty tough ones included, (some but not all.of fhose canopy formation related) but 80 - 90% of them not too much of a big deal.
But this one hit me hard out of the blue.
The very moment I cutted away, I found myself immediately in a very(!) fast flatspin, very(!) high forces, no chance to get it stopped or turned for way too long...
Looking into angular momentum I found a possible explanation.
Angular momentum consists of ground angular momentum and inherent angular momentum. As the sum of both needs to stay constant (as long as no "forces from.outside" come in to play to increase or decrease it), the inherent one needs to go up significantly the moment the ground one "collapses" = the moment you cut away...
Private messages I received talk about the same kind of experiences.
A danger I wasn't aware of - at least not to this extent - if it comes to ultrahighperformance parachutes and as fast as I spun I doubt that MARDs of any kind are the ultimate answer.... I gave all I had and it still.ended as a close call!

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One reason spinning line twists is so dangerous is that the harness puts you in a de-ached, back-to-earth, back-fly body position. Speeds are high enough that you are back flying. Altitude awareness is more difficult. You have a high decent rate and have to either look over your shoulder to see the ground, look at your altimeter, or fight the harness to get into an arch to get belly-to-earth.

When you cutaway, you could end up sub-terminal, on your back, and spinning. Without full airspeed to fly in, recovering stability takes longer than at terminal (with the same body position).

Having taught a lot of people to back fly in wind tunnels, people most often underestimate the power to turn their legs/feet have. They start to spin and tend to go with it, making it faster.

This is one reason I am not in favor of RSL's, but I am in favor of most MARD's. Getting the reserve out of the freebag after cutting away and traveling the length of your reserve lines just isn't enough time to allow for problems. With just the reserve PC out, you could entangle with it. You could end up with line twists as you may still be rotating as you hit line stretch. But I think that I would have a fully functional reserve over my head sooner (with a MARD) than cutting away, getting stable, and deploying my reserve.

Given that altitude awareness is more difficult with spinning line twists, high descent rates, high G forces, and the possibility of a high spin rate after cutting away, I use a Skyhook and don't try and fix spinning line twists. I just leave.

If you look at any picture of spinning line twists, they all show the same thing; line twists and the risers are uneven.

I fly a Valkyrie 84 (great openings), have magnetic riser covers (release evenly and before the canopy comes out of the bag), and a semi-stowless main D-bag (canopy comes out of the bag on heading every time), and I keep my hips even with the ground during deployment. All these things combine to prevent spinning line twists.

Derek V

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I have WS friends that often cut away but I seem to never have any issues. I think the two big factors are,
1. Your ability to fly and deploy straight...like keep straight through deployment.
2. Your wingloading.

I am very lightly loaded and have wonder what all the line twist talk is about. I did have some issues early on but thanks to a larger canopy, my twists were always stable.
Instructor quote, “What's weird is that you're older than my dad!”

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Hooknswoop


When you cutaway, you could end up sub-terminal, on your back, and spinning. Without full airspeed to fly in, recovering stability takes longer than at terminal (with the same body position).

Having taught a lot of people to back fly in wind tunnels, people most often underestimate the power to turn their legs/feet have. They start to spin and tend to go with it, making it faster.

This is one reason I am not in favor of RSL's, but I am in favor of most MARD's. Getting the reserve out of the freebag after cutting away and traveling the length of your reserve lines just isn't enough time to allow for problems. With just the reserve PC out, you could entangle with it. You could end up with line twists as you may still be rotating as you hit line stretch. But I think that I would have a fully functional reserve over my head sooner (with a MARD) than cutting away, getting stable, and deploying my reserve.

Given that altitude awareness is more difficult with spinning line twists, high descent rates, high G forces, and the possibility of a high spin rate after cutting away, I use a Skyhook and don't try and fix spinning line twists. I just leave.

If you look at any picture of spinning line twists, they all show the same thing; line twists and the risers are uneven.

I fly a Valkyrie 84 (great openings), have magnetic riser covers (release evenly and before the canopy comes out of the bag), and a semi-stowless main D-bag (canopy comes out of the bag on heading every time), and I keep my hips even with the ground during deployment. All these things combine to prevent spinning line twists.

Derek V



I had a few spinning malfunctions where I did not get stable after cutting away (no RSL, velo, WL 2.5).
I have video of one of the cutaways where I deploy on my back:
https://www.youtube.com/watch?v=LE4Hzrx8Q4U

My personal reason for not getting stable first and then deploying the reserve is that I believe it could easily take about 2000ft to get stable first, (which in combination with a jump from an altitude of 3000-4000ft which I often do seems too much)
To develop a habbit of getting stable first is something I don't want to become part of my reserve procedure.
http://www.dropzone.com/safety/Gear_and_Equipment/Top_5_RSL_myths_18.html
Quote

I keep seeing the same arguments made against RSL's, over and over. Many of them are just myths, word-of-mouth anecdotal stories passed down for so long that their original meaning has gotten lost. I figured I would list them here:

1. You should get stable before you open your reserve, and so you should disconnect your RSL.

First off, you should _not_ be stable face-to-earth when you open your reserve. The Racer manual spells this out explicitly - you should be head-high if possible to ensure a cleaner reserve deployment. Fortunately, you are head high the instant you cut away from your main, and that is the point at which an RSL will open your reserve.

Secondly, there are two universal truths in skydiving - you won't do it if you don't practice it, and you _will_ do what you trained to do. If you practice "cutting away and getting stable" you _will_ do that in the air, even if you someday cut away at 500 feet. If you do that, the only thing that will save your life will be your RSL.

Finally, before you decide that it's a good idea to cut away and then get stable, I'd recommend you do an intentional cutaway from a rapidly spinning canopy and see how long it takes. (Hint - it does not take just a second or two.)

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I m really curios to know what MARDs you don't like and for what reasons, PM welcome!

Maybe using the opposite effect of a pirouette could help, get into a tight bodyposition before you cut away. If you end up spinning after the cutaway,, get wide, this will decrease your rate of spin, hopefully to the point where it is way easier to deal with it?!

If the risers are not released absolute simultaneously, this should also have an effect, one way or the other, giving you less or more momentum to spin, depending on which one goes first (and what direction your main is spinning)?!

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I am not sture if "get wide if you get in a spin" would help. For Tandem sidespin`s it is teached that you need to bowl up you and the passenger to stop the spin....

alex

--
www.tandemmaster.net
www.skydivegear.de

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That was the reason for my post...

I am not sure


What is the common best practice to resolve a solo flat spin? I would still try to bowl up, but given that happend after cutaway, what else than pull silver would be a better option??

alex

--
www.tandemmaster.net
www.skydivegear.de

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A delta is better, but I wouldn't think adopting a fast fall position after a cutaway is such a good idea, especially if your altitude awareness has gone out the window.

Altitude is precious. After a cutaway you need to stop the freefall. Its no good being stable on impact.

ETA: And if your reserve is small enough to give you problems after opening, whatever the situation, it might be worth reconsidering your choice of gear.
My computer beat me at chess, It was no match for me at kickboxing....

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LeeroyJenkins

***I just had one of those cutaways ... I was also thinking to get small before cutting away just so it woud be easier to kil the momentum.



Tracking is the best way to get out of a flat spin.
[:/] After a cutaway?

More skydivers died because they pulled their reserve to late.

Pull the reserve, deal with the linetwist (if necessery) afterwards.

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ast4711

That was the reason for my post...

I am not sure


What is the common best practice to resolve a solo flat spin? I would still try to bowl up, but given that happend after cutaway, what else than pull silver would be a better option??

alex




I think you mean ball up (tucking in to make yourself small) rather than bowl up.

As a means of regaining stability, it is a waste of time and effort. Not effective. Especially after a cutaway.

As you said, pull silver.

Altitude is precious, not only to get your reserve out safely, but to give you time to find a safe landing area.

Again its pointless having a good reserve, only to land in the crocodile pool.
My computer beat me at chess, It was no match for me at kickboxing....

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I had a pretty bad spinning Mal at 2.5wl, and with the Peregrine Glide Ace Mard system, I cut away at the top of the spin and arched away from the spin the best that i could, and I had a perfect on heading opening with my PD OP 160. Thank you Kramer, for packing a perfect opening.

After that I would not unhook any type of Mard type system.

regarding HP wing's I am not a test jumper but:

if the wing is above your head with line twist you can kick out, but if the wing is below your shoulders with line twist chop it.

Trying to kick out of line twist with a wing in a dive is just wasting time. I would rather chop it early and have a beautiful reserve opening, than fight the line twist only to lose, and then have to kick out of line twist on my reserve.

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