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Zach Lewis Article - Skyhook Cutaways

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Not sure if this is being discussed anywhere else. but this was posted in Skydive Mag:

https://skydivemag.smallteaser.com/article/dont-hesitate

All good shit except for "Never blame the Skyhook (or other MARD) for line twists on the reserve."

A few things to iron out:

Zachs mal was very mellow by Velo standards.
He was line twist free under reserve because he was not twisting or spinning fast enough.
The assertion that if you cutaway quickly enough from a spinning mal on a skyhook equipped rig that you wont have reserve line twists is a steaming pile of shit.



I have personally seen most recent skyhook cutaways from high performance canopies result in multiple line twists. Keep in my my anecdotal experience is not statistically significant, but after my conversations with other my position is not uncommon. The line twists were not a result of failing to cutaway quickly enough. It was because the spinning was significantly more violent than that pussy slow spinning malfunction of Zach's. And by recently, I can refer to 6 this year alone. The only people I know who didn't have line twists after cutting award from a hard spinning high performance main are people who don't jump skyhooks.

Broken lines, line overs and tension knots can all create significantly more violent mals. The skyhook is a good piece of kit, but to overstate its apparent omnipotent capabilities is bullshit.

If you jump a high performance canopy and a skyhook, you have a high probability of ending up in line twists under reserve when you eventually have a violent spinning mal. This doesn't stop some people from jumping one.

*Edited to reword my post because Zach didn't write the article and it appears the editor has been very liberal in the use of artistic license to extrapolate as to causation.

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I have had 9 skyhook cutaways on sub 100sqft canopies and had linetwists on reserve once.
I think body position when cutting away has a lot to do with getting reserve twists.
That video you linked to, the guy barely tried to get out of the twists. I didnt read what height he was at and if he had altitude to have a go. Maybe he just didnt want to try for long. Fair enough.
But letting the canopy settle for a second makes it far easier to kick out regardless of whether it is diving or not.
Anyone flying a high-performance canopy should have the ability to be relaxed during a mal and be altitude aware enough to know if you have time (and how much) to attempt to correct the main before going to your last chance canopy.
A very fast spinning canopy cutaway will throw you straight out away from it, and provided you aren't flailing round like a muppet and are relaxed, there is no reason the reserve wont come out untwisted and on heading.
I dont know where that cutting away quickly notion comes from but that seems to me to be the best way to try and get reserve twists.
Far better i reckon (if you've commited you are definitely cutting away and you are not critically low) to let your body settle its orientation, whether that be skywards (spinning on your back) or facing the ground.

One more thing: everyone you know with both a skyhook and a high-performance canopy gets reserve twists everytime?
Maybe its not the skyhook they need to get rid of!

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Jon,

I suppose my issue with the article is that it takes a pretty simplistic view of a situation, when as you've pointed out, there is a lot more to it.

Fully agree on getting 'spin stable' prior to cutting away if you have time. Your track record is good but I also would expect most 'line twist only' mals to deploy a reserve without twists. I also wouldn't consider most of them violent mals.

Line overs/broken lines/line overs and anything that leaves the canopy deformed seem to be significantly more prone to line twists under reserve due to the nature of the mal.

And I never said to expect line twists every time. Just that it is a risk and it seems that if you keep jumping xraces loaded 2.5+ that it is not a rare or wholly avoidable occurrence.

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Hi there. I was the guy in the video.

I agree with you on the text about not blaming the skyhook for line twists on your reserve. The text in quotes was from me, and the rest was from the Editor.

I've had 3 spinning line twists cutaways, and that was my first with an skyhook (old school camera guy, never had an RSL/Mard before). My first one opened without line twist. The second one had a few minor twists, even after rolling over and taking a few seconds to slow the spin. I've seen many many skyhook spinner videos that had no lie twists, and a few that had several. It isn't a sure thing. Video here https://www.youtube.com/watch?v=dk0fSCtULxM

I can say this. I never felt like I was back in freefall with the skyhook. I was under reserve line stretch so fast, I didn't feel like I ever had time to get back into flying/falling in freefall. Defiantly wasn't as violently flung spinning on my back as I was in the video link above.

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The the result of line twists or not on a reserve deployment has *nothing*, read that again *nothing* to do with whether the rig is equipped with an RSL or MARD of any type.

Zero, zilch, nadda.
----------------------------------------------
You're not as good as you think you are. Seriously.

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Quote


The the result of line twists or not on a reserve deployment has *nothing*, read that again *nothing* to do with whether the rig is equipped with an RSL or MARD of any type.

Zero, zilch, nadda.



JP,
You beat me to it.

The canopy was deployed straight and then IT turned itself into line twist.
Seems to be a common problem with the OPT....

MEL
Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

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diablopilot

The the result of line twists or not on a reserve deployment has *nothing*, read that again *nothing* to do with whether the rig is equipped with an RSL or MARD of any type.

Zero, zilch, nadda.



I don't understand... Looking for a debate?

The jumper rotates in some fashion during a spinning mal and chops. Even though he departs any circular motion by flying off at a tangent to the rotation, any rotational momentum about any body axis is retained and the jumper continues to spin, which is subsequently reduced by drag or hopefully jumper action. (Or maybe made worse if not in control of a wingsuit.)

Case 1: Jumper has no RSL, takes time to slow and stop the spin, or get off his back, or whatever to get flat and stable, thus no reserve twists. (But is way lower on opening.)

Obviously if he pulls right at the chop then the reserve opening is essentially the same as an RSL activation.

Case 2: Jumper has RSL, might get twists. 99% (?) of the time not a safety issue.

Case 3: Jumper has MARD, it can work much faster and with more force to drag the reserve out, should be less likely to twist.

Twists can come from the bag and jumper rotating at different rates during deployment, jumper continuing to rotate through the opening when the canopy isn't rotating, or maybe occasionally the bag dragging past an unstable jumper's body. All it takes is half a twist and an asymmetry when the jumper is pulled upright (with uneven forces on each shoulder and not squarely beneath the risers), for the jumper to easily start rotating under the inflating canopy.

I could well be missing some subtleties or not have the experience to know the relative influences of different factors in practice, but the change in time to deploy the reserve must surely affect whether twists will happen?

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