Rank WS Features for Performance

[mccordia 74]

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I wish I had a biplane wingsuit, just like an AN-2

Get a tandemrating and a hot small girl that knows how to fly a wingsuit really well!?

JC
FlyLikeBrick
I'm an Athlete?

[Macthe 0]

So if aspect ratio is important then "webbies" will improve aspect ratio, more like a glider wing, they have giant aspect ratio's, but pylon racers in the old warbirds clip there wingtips for more speed, but then they do have engines.

If strength is a big factor then again the webbies will help you maintain the optimum position as one seems stronger than when reaching back for handles.

oh yes, Im going for webbies, :-)

the dream of flight

[KrisFlyZ 0]

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Take Cathy for example, Loic's wife, she can smoke a lot of people too with her "potatobag" wingsuit... And she has NOT the same size and shape as Loic...

And a skilled suit too

Sorry for the long winded post.

That suit is no potatobag. It has the right balance. i.e. It will put the flyer at an AoA closer to optimal.

I owned an S-Fly and liked it very much. It is for sale(in classifieds on here ) now by the guy that purchased it from me.

He has the same problem as me with it. He is an exact replica of me in height, Torso length and Inseam. The suit seems a bit wide across the legs(I laughed when I saw that in the classified text)...actually the problem is that the legs start a bit lower on that suit(as our torsos are shorter than that suit is designed for)...when that slack propagates down it becomes impossible to fly the legwing without flap.

This is a symptom I have had on my last 4 suits. It took me two years to figureout the problem. While talking about fit of the suit here is another interesting one.

When I purchased the Phantom, I weighed nearly 90kg with a big belly(remember that halloween pic, Matt). It fit me quite well then. Now, I weigh 73kg..after reducing the length by an inch and a half the suit is still about two inches or so loose in length.

On the flip side, whan I purchased my V-1, I weighed around 80Kg. Gaining the extra 10Kg helped me fly that V-1 without flap on the first jump....among other things. Because the extra length was taken up by the girth. Don't believe me...try and get someone the same height(smaller Torso length and same leg length)as you but of more girth to wear your suit....I will bet you money that the suit will end up short on length.

The extra width translates to length. I cannot put this in words but its something about volume and the suit taking the dimensions of the volume filling it....rather than having a definate shape.


Extra length makes flight by relaxing the legs(or not stretching the legwing very tight) impossible.

It has been published that to fly for max glide one must use a relaxed body position. The theory that I can come up with is that a relaxed body position allows the wings to make a bow(left to right...don't confuse with camber) and the airflow under the wing presses it up. In the 3D sense this gives the air over the top surface the best chance to stay attached...while creating clear channels underneath.

See Robi flying in the Phoenix-fly promo video from 2004...the one with all the jumps in China? We can see the legwing forming a nice arc as well as pressing up...this pushes the butt deflector up rather than flatten it. IMO, Even with the thinnest of rigs the butt deflector needs help to do its job well. In the attached pic...the arm wings need to come in quite a bit more. The well inflated Butt deflector has not covered much of the thickness of the rig. This picture was taken in the first few secs of the jump and the legs are relaxed...normally the legwing gets tensioned a lot more.

When we create lift with an attached airflow on both surfaces(usually the upper surface is a problem) the sensation is so obvious...it will be almost like being hit by a Mack truck in the face.

For me this happened on the first WS BASE jump for a few secs and never again. That is why I kept thinking it was somehow related to having total concentration.

Now, I know that this is near possible to reproduce without a suit that fits perfectly.

Why?

a) Flap is bad and it kills performance.
b) Extra length or girth translates to flap.
c) When we create camber(rolled shoulders and spine pushed up..gut sucked in) our lenth reduces...even with deep cut booties. To push spine up and have the suit cling to the body the torso of the suit must for perfectly and have no empty space.
c) A suit that fits an inch and a half or so loose cannot be flown relaxed without flap.

IMO, to fly for performance the suit fit is of paramount importance. Baggy does not work when it comes to wingsuits.

Even the most skilled pilot cannot fly a suit that is just a few inches too long.

If you have read all this sorry for wasting you time .

Kris.

[VectorBoy 0]

Get a hot small girl that knows how to fly a wingsuit really well!?

[piisfish 140]

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Get a tandemrating and a hot small girl that knows how to fly a wingsuit really well!?

-tandem rating : check
-hot small wingsuit girl : above my credit limit

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[SkymonkeyONE 4]

A lot of what you said was spot-on, Kris, but I am going to argue with you when you say that "even a skilled pilot cannot fly a suit that is a few inches too long". Very few of us find a perfectly-fitting wingsuit to try when we are either first starting or as we progress and want to try bigger and better suits. Personally, I would rather fly a suit that is a couple of inches too long than one that is prohibitively tight and does not allow me to point my toes. I have flown both extremes more times than I care to count. My Vampire fits me much looser than my S6 (the Vampire was cut for Scotty Burns), but I still fly it fine, with no flappage. I can't completely "stretch it out", but it definitely does not flap. Proper leg/feet positioning prevents that. Conversely, I have jumped several "perfectly fitting" wingsuits that I could not get to stop flapping (a Phi and a GS1). Odd.

Chuck

[The111 1]

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Come on Matt.

You know better than that. 10 kg heavier person is a thicker air foil. Shorter increases Aspect ratio by how much? A few hundredths.

No, I don't. That was my point. We are NOT super-efficient airfoils, most of us are gliding at LESS than 2:1 most of the time. Jeff Nebelkopf made a SINGLE SKIN suit and could glide well enough to keep up with people pushing it harder in inflatable suits. A very subtle airfoil change is incredibly negligible, compared to all the other factors that determine your G.R.

And another look at the height thing. A shorter person is not only shorter, but narrower (arm and legspan). So they are basically a "scaled down" version of the tall person. Why should a scaled down version glide any less well than a larger version? That's like saying that a Spectre 170 can glide flatter than a 120.

www.WingsuitPhotos.com

[Macthe 0]

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Come on Matt.

You know better than that. 10 kg heavier person is a thicker air foil. Shorter increases Aspect ratio by how much? A few hundredths.

No, I don't. That was my point. We are NOT super-efficient airfoils, most of us are gliding at LESS than 2:1 most of the time. Jeff Nebelkopf made a SINGLE SKIN suit and could glide well enough to keep up with people pushing it harder in inflatable suits. A very subtle airfoil change is incredibly negligible, compared to all the other factors that determine your G.R.

And another look at the height thing. A shorter person is not only shorter, but narrower (arm and legspan). So they are basically a "scaled down" version of the tall person. Why should a scaled down version glide any less well than a larger version? That's like saying that a Spectre 170 can glide flatter than a 120.

If you had an F16 that flew at 1000mph
then scaled it down till it weighd an ounce, there would be no way it could go as fast,
it seems to me

[KrisFlyZ 0]

You are right Chuck. My bad, I did not make the point properly. And very good point on too small is more difficult to fly than too big.

Just trying to say this...

Get a suit too big and your performance, consistency will suffer. We can stretch our body to an extent and fill out a suit that is slightly big, a few more inches bigger and it becomes impossible to fly it at the same efficiency as the suit that fits us well.

Kris.

[SkymonkeyONE 4]

You, or someone else in this thread, mentioned another pertinent point: "magic." There are some flights where you get out (or leap off) and your suit seems to instantly hit the sweet spot and you know it right away. There are other flights where you can replicate every single variable possible and you simply never get that "pop." You fidget around and tweek your position all you like, but you know you just never hit it. My very first flight on my S6 out of the Otter at Z-hills was a whopping 159 seconds. I have not replicated that time since, whether trying to or not. Oddly, it didn't feel like I was doing anything special at all on that flight. The only variable on that flight that I can think of that has changed since is that the mylar was not yet destroyed on the suit (particularly in the legs).

Chuck

[KrisFlyZ 0]

You are absolutely right, we are crappy airfoils.

This is the explanation I have in my mind...may not be right....

Jeff N, flying almost as well(or better) as the others in the single skin suit.

Can you guarantee that the flight is at a super efficient AoA? My bet is that it is in a stally configuration....

AoA = ATAN(D/L) (-/+) pitch (-/+) Angle of Incidence

AT 2:1 GR this is 26.5 degrees(at lower glide the angle is even bigger)....at this AoA, the double skin suit will effectively become a single skin suit of lesser area.

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And another look at the height thing. A shorter person is not only shorter, but narrower (arm and legspan). So they are basically a "scaled down" version of the tall person. Why should a scaled down version glide any less well than a larger version? That's like saying that a Spectre 170 can glide flatter than a 120.

Can't answer that theoritically.

Kris.

[The111 1]

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If you had an F16 that flew at 1000mph
then scaled it down till it weighd an ounce, there would be no way it could go as fast,
it seems to me

I was not talking about speed. I was talking about glide ratio. The word "fast" cannot describe a glide ratio.

Moreover, we are not talking about scaling factors that large. We're talking about maybe 10-20% size changes in the human body.

www.WingsuitPhotos.com

[Professor 0]

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That's like saying that a Spectre 170 can glide flatter than a 120.

A Spectre 170 does glide better than a Spectre 120. Scaling is a difficult challenge.

Ted
Like a giddy school girl.

[KrisFlyZ 0]

The question we started with was different.

Will the same person if he was 5 inches shorter and 10kg heavier make a poorer glider than the original?

Kris.

[robibird 3]

Yes It will!!!He is 178 tall and 98 kg heavy

Robert Pecnik
robert@phoenix-fly.com
www.phoenix-fly.com