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Squirrel Snatch - New pilot
Does anyone have any thoughts, video or info about the new pilotchute from squirrel? Especially with SD configuration?

From what i read on their website i think the weight and consistency of inflation seems really interesting. But it looks wierd and i have no idea what i'm talking about.
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Re: [stayx] Squirrel Snatch - New pilot
Its just a PC with the vents closer to the edge of the zp.
In my opinion though, I believe vents are most effective right at the apex of the inflated PC. I think they wanted to be different though, regardless and moved the vents even further then anyone else.
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Re: [Shredex] Squirrel Snatch - New pilot
Shredex wrote:
Its just a PC with the vents closer to the edge of the zp.
In my opinion though, I believe vents are most effective right at the apex of the inflated PC. I think they wanted to be different though, regardless and moved the vents even further then anyone else.

wow incorrect! you ever actually seen one of these?
I have and its different
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Re: [wasatchrider] Squirrel Snatch - New pilot
Some hi res video on a jump would be cool.

How different is it from the Toxic?
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Re: [base698] Squirrel Snatch - New pilot
Tom, I'd be curious to hear your thoughts on this. You're a fan of the Toxic, and with good reason I believe.

Is this design inherently better than the toxic? Or is that debatable? The Squirrel marketing seems to imply that everyone would already be using this design if it weren't for the cost of production, which is a problem they claim to have solved.

Interesting to note that the Snatch is around the same price point as the Toxic (actually $15 cheaper)...so they are fighting for the same market.
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Re: [Shredex] Squirrel Snatch - New pilot
Shredex wrote:
Its just a PC with the vents closer to the edge of the zp.
In my opinion though, I believe vents are most effective right at the apex of the inflated PC. I think they wanted to be different though, regardless and moved the vents even further then anyone else.

theres both an apex vent, and the outer vents on the far surface of the ZP. same thing that marty did, only he used F-111 in the apex and then an outer vent of thin mesh.

ive got my 42 toxic as my workhorse PC, and everything else is standard ZP AV. im not gonna replace my entire arsenal with 200+ dollar pilot chutes, thanks very much
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Re: [stayx] Squirrel Snatch - New pilot
I found it to be consistent in inflation, snatch force, and minuscule oscillation on every jump so far. I also like how it folds up and fits in my BOC. Plus the construction by squirrel is amazing compared to my other pilot chutes (even my toxic which is pretty amazing). I really trust this design for all types of jumps. Just my $0.02 I added a photo of a 38" doing it's thing in a pretty good cross wind. Stayed pretty much solid right there.
image.jpg
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Re: [OuttaBounZ] Squirrel Snatch - New pilot
wow rainbow-coordinated gear
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Re: [Shredex] Squirrel Snatch - New pilot
Shredex wrote:
In my opinion though, I believe vents are most effective right at the apex of the inflated PC.

Actually, the highest areas of pressure inside an inflating/inflated round parachute are not at the apex. This is why (or at least one reason) many newer pilot chutes moved the vents further away from the apex.

Will was at the Mustache Boogie, showing us his Snatch Wink, and giving us an overview of the theory, design, testing, etc. The history, photos, and testimony were pretty damn convincing that the pilot chute is truly different, not just different looking.

~ Chris
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Re: [sky12345] Squirrel Snatch - New pilot
Found a pic on dropzone. Actually that looks like a really good design. I work with a baloot style drogue with a burble fence. That's essentially what you have here in a disk/gap/ring design of a parachute. The location of the perimeter vent creates an out flow at that point on the surface. In a since it creates a sharper radius an causes flow separation at that point just like a burble fence. It keeps the point of separation stable and stops the parachute from osculating. To be clear it's asymmetry in the flow separation that causes osculation.

It looks pretty good. Vent might be a little high and I'm not sure about the half angle at the bottom. The cone of mesh might need to be a bit longer for it to be ideal. The real proof is in whether the thing osculates and breathes. Vid in a wind tunnel would be nice.

I've always wondered why we don't build better PC's. It's just such a pain and I've never been sure if it would actually be worth the trouble.

Lee
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Re: [RiggerLee] Squirrel Snatch - New pilot
Not a video but...




Sounds pretty interesting. Here is what they are saying about it.

In reply to:
HISTORY

The Snatch project began after a conversation between Squirrel Co-designer, Will Kitto, and CRW expert, Jim Rasmussen. Although the toroidal design concept has been used extensively in parachutes for over 40 years (it is also known as an annular or pulled-down-apex (PDA) design), it has never before been adopted for BASE or skydive pilot chutes due to the complexity of the design being cost and production prohibitive. However, with access to an advanced production facility and with no barriers for cost of production, producing the toroidal design is viable.

THE DESIGN

The Snatch’s three dimensional partial toroidal shape is joined together with two mesh cones. The torus shape, like a donut cut in half, has a very high drag coefficient. "Traditional" base and skydiving pilot chutes are a very loose approximation of this same shape. Traditional PCs are two circles sewn together around the edges, typically one of ZP and one of mesh, with a piece of line or webbing connecting the center of each circle together at a specific distance. When pulled from the center of the mesh circle and dragged through a fluid, it inflates into a rough approximation of a pulled-down-apex shape, but with a large amount of distortion and error, with a wrinkled and asymmetric circumference. Imagine crumpling up a single piece of paper until it forms the 3D shape you want to design - it won't look good, nor be an accurate representation of a 3D surface. Yet that is the current basis of traditional PCs: an approximate and inefficient 2D design meant to perform a task that requires a 3D shape.

The Snatch’s design achieves a specific 3D shape when inflated by using multiple panels (gores), each with a mathematically calculated 3D shape. The design is similar to the way that round parachutes are designed from multiple gores to form a hemispherical shape when inflated.

THE MATH

A torus is made by rotating an ellipse around a center axis. For this design, we used an ellipse with a ratio of 7:10 (height : width) with an axis offset from the ellipse by 20% of its width. Mesh cones meet with the outside and inside edges of the partial torus at an exact tangent to its curve, ensuring a smooth transition from mesh to ZP, which maintains a smooth and error-free perimeter of the pilot chute. The difference between a Snatch and a traditional PC design is immediately apparent when handled or inflated by any experienced jumper.

HOW IT WORKS BETTER

The inherent imperfection of the standard double circle pilot chute design means that there is a significant amount of randomness in its inflated shape. There is a constant tug-of-war between air pressure forcing it into a 3D shape, and the fabric trying to remain a 2D shape. Across its surfaces there are sections of high and low stress, where there is too much material in one section and not enough in another, causing "stretch and sag". This can contribute to the pulsing and surging we see in traditional pilot chutes in freefall. A toroidal design minimizes the randomness and helps to ensure that the inflation is more consistent and predictable. Once inflated, the pilotchute is not searching for alternative shapes: it inflates to its intended shape and stays there. There is no pulsing, and instead only a clean inflated shape.

WHAT THIS MEANS TO YOU, THE JUMPER

Per square millimeter, the Snatch pulls with more stability than a traditional PC. Wind tunnel and field testing have shown vastly superior stability in all BASE applications, from low slider-down to wingsuit and tracking deployments.

WEIGHT & BALANCE, AND MATERIALS

We believe pilot chute weight to be a critical safety factor. For over a decade now, the BASE community has known that hacky-sack-handles are bad, and contribute to PC/bridle entanglements because of their weight. Yet there are still countless PCs in use today which feature heavy and bulky PVC handles, excessive load tape, and overbuilt/clumsy construction. Evidence suggests that lighter is better, and for that reason we have created the lightest design that we could without sacrificing reasonable durability. A lighter PC is less likely to entangle with the bridle: it tumbles less, and is carried downstream at rates more similar to the bridle. A heavier PC can be carried downstream at a slower rate than the bridle, which can cause the heavy PC to then tumble and mix with the bridle in the jumper’s burble.

HEXAGONAL CARBON HANDLE

The hexagonal carbon-fiber handle design is the result of our lightweight obsession. It provides a distinct easy-to-feel shape, with the absolute minimum in weight. The carbon hex is present on the 32, 34, 36, and 38 sizes. The 42 size features a pad-patch top, with no carbon. The 46 and 48 are handle-free, for hand-held use.

QUALITY AND PRECISION

Each Snatch is guaranteed to be symmetric in construction. PC symmetry is critical - while there are many factors that can cause a pilot chute to exhibit unstable behavior, ensuring that your PC is built symmetrically is important to ensuring stable parachute extractions. The Snatch is built to +/- 1mm tolerances. Outside load tapes and the center line meet together at a single bridle attachment point, for ease of attachment and symmetry.

WHY WE ARE OPEN SOURCING THE DESIGN

The toroidal concept was not invented by Squirrel, and has been in use in the military and civilian parachute industries for decades. In addition to that, we feel that the benefits of this design are such that all BASE jumpers should consider using it. For that reason, the Snatch patterns can be downloaded for free, just email us to receive the link. All sizes are available, in 2D patterns ready to be printed or plotted, and sewn. The files available can be opened with all common CAD programs, many of which can be found for free online.
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Re: [base570] Squirrel Snatch - New pilot
This is a better effort then has ever been put in by a skydiving manufacturer before.

As to their math. An ellipse is actually not the ideal shape there. There are some things you can do that are fairly simple like looking at the curvature of that surface in the radial direction as a function of the radius, if you were going to treat is as a simple inflated object. By changing that ratio you can create a full spectrum of curves which would form a stable inflated surface. Their was a Russian paper presented at PIA many years ago studying drogue design that really addressed it well as a panel problem solving the set of differential equations through an iterative method. I don't recall all the details but that was probable the best and most in-depth solution that I recall seeing.

If people wanted to start playing around with this I think it would be cool. It's not hard to create a pattern set like this. Any body with Exel can do it. I think the real question is whether it's worth the added effort to build the things.

Lee
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Re: [Shredex] Squirrel Snatch - New pilot
Shredex wrote:
Its just a PC with the vents closer to the edge of the zp.
In my opinion though, I believe vents are most effective right at the apex of the inflated PC. I think they wanted to be different though, regardless and moved the vents even further then anyone else.

Your opinion doesn't matter since they are dealing with numerical based facts that have been calculated, tested, and proven. So my opinion is you should trust science more than your unsupported assumptions if you want your posts to be taken seriously.

Wink winky face to make this a friendly post.
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Re: [OuttaBounZ] Squirrel Snatch - New pilot
OuttaBounZ wrote:
Shredex wrote:
Its just a PC with the vents closer to the edge of the zp.
In my opinion though, I believe vents are most effective right at the apex of the inflated PC. I think they wanted to be different though, regardless and moved the vents even further then anyone else.

Your opinion doesn't matter since they are dealing with numerical based facts that have been calculated, tested, and proven. So my opinion is you should trust science more than your unsupported assumptions if you want your posts to be taken seriously.

Wink winky face to make this a friendly post.

It really does make it all better <3 :]
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Re: [stayx] Squirrel Snatch - New pilot
Been looking for a new PC to fill the gaps in my line-up. Looks interesting.
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Post deleted by W_Heisenberg
 
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Re: [W_Heisenberg] Squirrel Snatch - New pilot
enough posting online. get off your lazy ass, and go please your mistress.
marys waiting for you, legs spread, moist as hell, and real yeasty and unshaven. shes bleeding too for the next week so go get your red wings for the thousandth time!!!!
you a nasty dog!
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Re: [base570] Squirrel Snatch - New pilot
Can you post a picture of the hex handle?
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Re: [dandandan] Squirrel Snatch - New pilot
Here's a link to the site. Click on "carbon handle"

https://squirrel.ws/snatch