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yuri_base

Z-Experiments with V-2

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Yo Fuckerz!

Happy New Revolutionary 2007 Year, all!!! ;)

Made a bunch of experiments with V-2 at Z-Hills, it was a lot of fun!

1. Experimented with ankle weights from 0 to ~15lbs. The best glide seemed to be with Hanwags and 5lbs. weight. The glide (flying relative to clouds) seemed to be INSANE, visually similar to Spectre with rear risers maxed out. ~3.0??? The damn thing just wants to fly! It just wants to fly forward FAST while it is barely moving down. It felt scary, as if something was wrong... "It's like cocaine"!!! ;) It's unbelievably fast and perfect flying machine! It flies almost as good as Maggot tracks! :P

2. Unfortunately, V-2 has [at least, the way my suit fits me] an arm wing inflation problem. That's why the ankle weights are required to compensate for the loss of lift/balance from the arm wing. By looking at the arm wing on several flights, I noticed that it looked like it was not inflated properly. It looked lacking the internal pressure and the same wrinkles that I observed while lightly stretching the wing on the ground were observed in the air as if there was no internal pressure to smooth them out. The trailing edge of the wing was flapping like crazy unless there was a very specific amount of stretch applied to it. In comparison, Phantom wing looks nicely inflated and "puffy" in the air, with a lot of range in lift. The V-2's wing, in comparison, seemed to be "dead", static.

3. I noticed that the arm inlets are wide open, but they seem to be pushed back by the wind so much that they are blocking the opening itself. Inserted the halves of Gatorade bottle cut lengthwise to insure the openings are forced open, and the inflation returned, with much more lift from the arm wings. Now, the balance was thrown the other way around, I was much more flat with the horizon and the glide (relative to clouds) noticeably suffered. After ~40 flights on misbalanced suit, I had to relearn it again! I was also very tired by then and could not achieve any decent glide. The glide seemed to be similar to that of Prodigy pants alone.

4. Experimented with making the leading edge sharper by inserting the long "animal" balloons into arm wing. The lift was so insane that I couldn't hold my arms level. They were swept back. The glide was terrible. Total misbalance and stall of the suit. With this better profiled arm wing, it needs larger (longer?) leg wing to restore the balance and best AoA. The sharper leading edge is definitely something to be looked at to improve L/D.

5. By using VISO and its instant speed vs. time replay feature, I noticed that the vertical speed for the best glide was ~50mph, vs. ~42mph for the longest freefall times (my exit weight is 260lbs.; the speed is proportional to the square root of wingloading). So if you're trying to perfect your glide, don't try to minimize the fallrate: add ~20% to your minimum possible sustained fallrate, match that and achieve maximum horizontal speed you can achieve, and this will give you the best glide.

No hard data yet, but it'll be there when PFM System is out! ;)

Yuri
Android+Wear/iOS/Windows apps:
L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP
iOS only: L/D Magic
Windows only: WS Studio

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Sounds kinda like you're having the same issue that KrisFlyz did, some kind of installation or fit problem.
"The evil of the world is made possible by nothing but the sanction you give it. " -John Galt from Atlas Shrugged, 1957

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All,

I've removed several posts of brand warfare from this thread. If you want to rave about your brand, or trash your buddy's, please start a separate thread to do it rather than side tracking technical discussion.

There were a couple reasonable comments that got caught in there, too, so if you had one of those, feel free to post it again, and apologies for removing it.

Thanks!
-- Tom Aiello

Tom@SnakeRiverBASE.com
SnakeRiverBASE.com

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Hello Yuri,
Will go slow trough your letter in order to put some comments and also to help a little to other reader.
All in all I am happy to see you playing w the suit and test them . No doubt this way is one of the best ways to learn how to fly, and become good flyer.
Nice job, continue w this.

1. Happy to see that you getting the feeling about moving forward. This is why we wear WS :)
placing weight to legs is one of the ways to get the better glide. Works well for those people who has weak stomach muscle and legs.
For good glide ( performance ) we need the de-arch position. Hips up, legs straight. Belly should be suck in to the body , not hanging out!
Well, all this is hard and not really pleasant.
Common mistake is compensation of incorrect body position by pulling the wings down, more , more and more... this leads to stall and unstable falling, while sending ''right'' perception of slow decent rate!

I suggest you to get stomach and legs stronger instead of hanging weight to legs ( quit bad idea on hiking to the summit :) )

2-3. Arm wing inflation problem: I am surprised you have problem w this! One of the biggest advantages on V2 and PF vents is the increased pressurization. This is what most of the good flyers feel after very few jumps. While on my previous designs (Skyflyer 3) the wing pressure become weaker as faster and flater flight was, on V2 or Phantom is opposite! Make sure that arms are in proper position and that you are not falling in stall position.
Also, make sure your shoulders sits symmetrical.
Vent position is on the correct position and works well on over hundred V2's.
Gatorade bottle - good old Russian improvisation style - which I like a lot! :)
Robert Pecnik
robert@phoenix-fly.com
www.phoenix-fly.com

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placing weight to legs is one of the ways to get the better glide. Works well for those people who has weak stomach muscle and legs.
For good glide ( performance ) we need the de-arch position. Hips up, legs straight. Belly should be suck in to the body , not hanging out!

I do it because I'm lazy B| I have no problem admitting that.
But couldn't it also improve the airflow because your body is more straight while still maintaining an increased angle of attack as compared to trim without the weights?
I'd like to think it's not just because I'm lazy :P
Johan.
I am. I think.

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Sounds kinda like you're having the same issue that KrisFlyz did, some kind of installation or fit problem.



It was purely a problem with the way the harness sat on the shoulder. Once that was sorted, inflation was not an issue.

Since we are talking about fit and performance and weights. I always believed that flying for glide involves flying with complete concentration and 'holding' the correct angle.

Unfortunately, it is not possible to hold an angle(I think now that practice or 100s of jumps will not enable someone to hold that angle for the longest time)...it takes too much effort....and the slightest lapse of concentration has put me in a stall. However, if the balance of the suit is such that it puts us in a position of close to optimal AoA the best glide will come automatically. For instance...I(IMO) got best glide from the V-1 by cutting back on the arm wings but keeping the leg wing stretched...less effective arm area and less effective total area but better balance. More area of the leg wing meant that I would be tipped to a lesser AoA. Flying flat with the horizon and gliding at 2.0 puts us at an AoA of 26 degrees. If you subtract the 3 degrees (angle of arm wing incidence ) its still pretty high 23.

If the legwing to arm wing distribution puts the wingsuit at 10 degrees below the horizon then the AoA will be 13 degrees and in a higher lift and a lower drag configuration. Putting the wingtips up as described below also reduces the drag a lot. According to this theory....people with longer legs and shortish torsos will be able to fly naturally at an AoA that is close to optimal and thus easily glide well.

I have heard people say put some camber into the arm wings(with the V2 wingtips and the Phantom wing tips the entire bottom part of the wing can be bent like an airplanes wing at landing time)...I don't believe that putting camber into the arm wings is best glide configuration. Getting the legs down and sucking the gut in or like in my case loosing it all(I had a proper pumpkin tummy last October :D) is the best way.

Kris.

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I do it because I'm lazy B| I have no problem admitting that.
But couldn't it also improve the airflow because your body is more straight while still maintaining an increased angle of attack as compared to trim without the weights?
I'd like to think it's not just because I'm lazy :P



No aircraft designer adds weight to their design, which adds nothing for performance, before trying to better balance the existing weight in the design to keep it light weight and balanced. Keeping the weight ( and drag ) down is free performance.

Move your cameras down to your ankles if your too front heavy. :D

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I do it because I'm lazy B| I have no problem admitting that.
But couldn't it also improve the airflow because your body is more straight while still maintaining an increased angle of attack as compared to trim without the weights?
I'd like to think it's not just because I'm lazy :P



No aircraft designer adds weight to their design, which adds nothing for performance, before trying to better balance the existing weight in the design to keep it light weight and balanced. Keeping the weight ( and drag ) down is free performance.

Move your cameras down to your ankles if your too front heavy. :D



An aircraft designer has a degree of freedom that we don't. We can't control the weight distribution in our bodies.

BTW, when flying certain gliders (such as the Schweizer 2-33) solo, you HAVE to add weights to keep it in trim.
...

The only sure way to survive a canopy collision is not to have one.

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An aircraft designer has a degree of freedom that we don't. We can't control the weight distribution in our bodies.

BTW, when flying certain gliders (such as the Schweizer 2-33) solo, you HAVE to add weights to keep it in trim.



I've got more than a few hours in the Schweizer 2-33 and am aware of the added weight when solo. I realize there are exceptions however rare. But you know if the man could have rigged it without the weight he would have.

Do you know any designer that just sets out to add weight before an exhaustive trial using other means for balance?

I actually feel out of balance with too many cameras on my helmet. Flying is best with a clean noggin.

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An aircraft designer has a degree of freedom that we don't. We can't control the weight distribution in our bodies.

BTW, when flying certain gliders (such as the Schweizer 2-33) solo, you HAVE to add weights to keep it in trim.



I've got more than a few hours in the Schweizer 2-33 and am aware of the added weight when solo. I realize there are exceptions however rare. But you know if the man could have rigged it without the weight he would have.

Do you know any designer that just sets out to add weight before an exhaustive trial using other means for balance?

I actually feel out of balance with too many cameras on my helmet. Flying is best with a clean noggin.



So you have bought a wingsuit and you determine that it is not in perfect trim for optimum performance. Is it better to (a) add weight to correct the trim? or (b) adjust to a sub-optimal body position to correct the trim? or (c) just fly it out of trim?
...

The only sure way to survive a canopy collision is not to have one.

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So you have bought a wingsuit and you determine that it is not in perfect trim for optimum performance. Is it better to (a) add weight to correct the trim? or (b) adjust to a sub-optimal body position to correct the trim? or (c) just fly it out of trim?



To change trim (d) change body for optimal trim. We have a lot of control of the angle of incidence on our wings that rigid craft don't have. We can do that unless we run out of pitch authority and I don't believe any of the wingsuits have this problem.

In the case of the Ballast in the Sailplane when flown solo, I'm pretty sure it to keep it from being loaded well beyond its aft most center of balance were it does not have enough pitch authority to recover and stall/spins/crashes.

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Yo!

Made a few more flights today with my ghetto V-2. I mean, look at this shit!!! ;) (***pics Not Safe For Work!***)

Used a piece of a bicycle inner tube taped inside the wing to form a better leading edge. The performance is noticeably better. The balance is just about perfect, no weights needed anymore. The jury is still out on whether the wing is inflated properly, the flights with Gatorade Inlets™® and without them felt about the same, wing looked about the same. They were positioned poorly though. Further experiments with better designed inlets will show.

To answer some questions...

- Scott: 15lbs weight is total, for both legs. Having 7-8lbs on each leg makes legs pretty numb on landing.

- Fabien: animal balloons proved to be impractical, they blow up too easily. Inner tube is much better. So I posted pictures of better balloons. ;)

- Pendragon: chest strap is tight, the vents are well outside the harness. In fact, too much outside, so tension creates wrinkles in the vent area; this poor fit is probably the reason they don't work properly.

- Robi: weights are only a research tool. They are the cleanest way to change the pitch angle without changing the shape of the suit or body position. Once the sweet spot is found and its pitch angle and horizontal and vertical speeds are "memorized", the next step is to try to achieve the same balance aerodynamically, by adjusting the lift from arm and leg wings. One way to do it is to degrade one of the wings (e.g., reduce the pressure and partially collapse the leg wing in order to increase the pitch to more head-high). The overall result in this case depends on whether the improvement from the better AoA outweighs the decreased quality of the wing. The better way is to achieve better balance by improving the quality of the affected wing. Just like the better leading edge did.

It would be awesome to see inflatable pouches in arm and leg wings to morph the wing profile and even size&shape in the future versions of your high-performance suits! So that the flyers can fine-tune their balance with a little pump (included). :)
So let the high-performance WS Revolution begin!!! Here are my goals for 2007:

- build a system (called PFM System, PFM for Pure Fucking Magic ;)) to accurately measure L/D (acceleration-corrected) and horizontal/vertical speeds (true airspeed - wind and thermals independent) in real time. You will hear in the earphone a sexy voice, "2.4.... c'mon, fucker, you can do better! your horizontal speed is only 90mph, increase it to your sweet spot of 115mph.... 3.0... good boy! 4.0... Are you Maggot?!" :)
- measure the V-2's (with modifications) polar curve by varying the pitch angle using weights, find the sweet spot. Draw the coefficients of lift and drag as functions of AoA. These curves are golden, they will provide a lot of insight!

- enhance V-2 with better profiled arm wings, inlets. Possibly move the leading edge of the leg wing down, to where the mylar ribs start (about knee level), to form a wider, better profiled, "stand-alone" wing. Experiment with removing the back deflector altogether, it may have a negative influence on the stand-alone legwing.

- by enhancing the suit, balancing it and flying with real-time feedback system, achieve instant and precise muscle memory for stable L/D = 3.0 flights 95% of the time.

- share my results with others

Wake up, everybody! Together we can make some amazing things! Think, invent, experiment, fly, share, repeat. :)
Yuri
Android+Wear/iOS/Windows apps:
L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP
iOS only: L/D Magic
Windows only: WS Studio

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Wow! Outstanding, magnificent work! The photographs reveal the skill and craftsmanship as well as pure artistic talent that you have put into the suit modifications. Well done, A+! ;):)
"The evil of the world is made possible by nothing but the sanction you give it. " -John Galt from Atlas Shrugged, 1957

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OK, cat's out of the bag on this one! Here's a pic of a more refined version. Note the white strap is wide velcro, inner tube is sealed on the ends with one fold and contact cemented inside and out...let the aerodynamic discussions begin!

Things to consider if anyone tries this - on climb to altitude, pressure outside decreases and inside the inner tube stays the same, hence it increases in volume (more pressure in your arm wing). At altitude I stand in the plane with my arms straight out in flight mode starting at around 10k.

Second caution, on deployment arms have some small pressure due to the inner tubes so pull high on the first flight test.

Sorry no models for the back drop!

Long flights!

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Just a quick note here. I made several jumps with Yuri when he was tinkering with his weights and I while he did pull away horizontally from me towards the end of the skydives, he was also dropping out. I was able, in my S6 to catch up to him after he pulled far below me, then (from hundreds of feet higher) rip a 180, swoop him under canopy, then fly another twenty seconds before I pulled.

If it's a race to get a certain distance away from your exit point, then I guess he wins. That said, I could have gotten much farther away by the same pull altitude in my suit. Actually, either of my suits. Yuri is a much bigger guy than me though. Moose, in Scotty's V2 and as compared to Yuri, seems to have more vertical range. I think it's his Swedish body type. You know, long torso and lighter weight.

I did not jump with Yuri after he "fixed" his vents. He did solos on all of those jumps and the rest of us were flocking, so I have no report as to how those jumps went for him. One thing I can tell you for sure though: you would never catch me jumping leg weights like he was doing. You ought not have to do such things just to get a suit to fly comfortably.

Chuck

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Chuck, that was a flight with a total of 15-18lbs. on my legs (Hanwags + 2 ankle weights 5lbs each). Total exit weight was ~275lbs. This flight was stally, unstable, and with poor glide ratio. I then started reducing weights and that's how I found the sweet spot for my particular suit and body type: Hanwags + 2.5lbs per leg. In this configuration I was able to fly at a glide ratio that visually eclipsed anything that I've ever had before, including planeouts with Phantom at 2.9.

Changing the leading edge with tubes eliminated the need for weights.

You should have jumped with me on one of those optimized flights! ;)
Android+Wear/iOS/Windows apps:
L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP
iOS only: L/D Magic
Windows only: WS Studio

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I don't know this for a fact, but I'm guessing that the primary difference between you and Yuri (that's Yuri A, not Yuri K) is not suit, or weights, or even body type, but overall wingsuit skill level. To say that you could smoke a particular person in whatever suit/configuration doesn't really show anything, simply because you could smoke almost anyone in any suit/configuration.
-- Tom Aiello

Tom@SnakeRiverBASE.com
SnakeRiverBASE.com

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:D:ph34r::D

Nuh Uh!!! oh yea?! Well my dad can beat up your dad!
My big wheel scooter is faster than yours!! :D

A bit more seriously though, so that this post has something to do with the topic instead of just being a thread drifter... : It would be good to have a couple other birds (1 from each manufacturer perhaps or people that flew with him before the mods) go flying with Yuri and his latest developments to see if he's changed the suit at all.
"The evil of the world is made possible by nothing but the sanction you give it. " -John Galt from Atlas Shrugged, 1957

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Jeff does have tremendous range in his Mach1, but he is also two inches taller than me and possibly five pounds lighter. I will also say that Jeff has more time backflying than most other people have on their belly in a wingsuit. There have been a total of zero other people who have flown that suit that have gotten away from me. There have been a ton of people here try though.....:PI might end up with one just for shits and grins, but at this point I think my first Tony wingsuit will be the Aerobat.

Chuck

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Why use an inflatable tube which isn't pressure stable when a foam noodle would seem to work just as well without changing shape at altitude? Also a foam insert could be carved to a complex shape easily. I'm impressed that a seemingly small change in leading edge shape gives such dramatic results. I've been considering adding a triangular trailing edge to the arm wings to slightly increase surface area particularly near the body where it won't cause much arm strain and where the airflow is already dirty.
Sometimes you eat the bear..............

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