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HGpilot

Slow flight ?

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I think there is a basic difference in what you and I are trying to achieve. Slow flight in a wing suit does not interest me very much.

I guess for your design goals, the wings can be attached with a positive angle of incidence like on the Rigor mortis or the Giboline 3(posting from memory, so definitely check that) . At neutral wrist position, the wings will have washout already. A wings with a slightly longer trailing edge than the arm will allow the forces to push the wing trailing edge up and help(as seen in practice already).

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No. I'm impressed with the performance increase my V2 has in comparison to the my Classic2.
Anyone would be .
However performance gains seem to be slowing down now .



Does that have something to do with diminishing returns in performance with increasing area due to no change in span but increase in area? Or worsening Aspect ratio and thus more induced drag?

AR = (wingspan * wingspan)/WingArea

http://en.wikipedia.org/wiki/Lift-induced_drag

Induced drag decreases with speed but bigger wingsuits being slower overall at best L/D must be worse off relatively than their smaller counterparts in this regard. As we cannot simply increase wing area and add taper to the wing geometry, the increasing length of that baton(wingtip) to make a bigger wing suit must contribute negatively as well. Diminishing returns again?

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in reply to "Does that have something to do with diminishing returns in performance with increasing area due to no change in span but increase in area? Or worsening Aspect ratio and thus more induced drag?

AR = (wingspan * wingspan)/WingArea

http://en.wikipedia.org/wiki/Lift-induced_drag

Induced drag decreases with speed but bigger wingsuits being slower overall at best L/D must be worse off relatively than their smaller counterparts in this regard. As we cannot simply increase wing area and add taper to the wing geometry, the increasing length of that baton(wingtip) to make a bigger wing suit must contribute negatively as well. Diminishing returns again?

......................................................


Even though your interests lie elsewhere I appreciate your thoughts on this subject.


As you say adding wing span doesn't solve the L/D issues without adding new problems.
I'm guessing if the wing extensions were particularly slippery and yes non-fabric then the diminishing return limitations could be pushed out a bit.
Handling the extra leverage from extra wings would imo need a throughspar of some kind.
It seems possible that a fishing rod type spar would help take some loads and still be compact and lightweight.

If the wingtips were gradually increased in size then an optimum tip area/load/spar size and weight could become apparent.

Since seeing Gisellemartins design concept (prototype?) with its extended wingtips , it has struck me that the basic aerodynamic idea is sound. Forming the idea into a workable wing is another thing.


I've ad some fun the last few hours throwing together a few of the ideas including washout and wingtip extensions and yes reducin the aspect ratio.
The result is in the attachments.

Just a very rough concept model but the possibilities seem to be there. The wingtips could be made to fit over a fabric WS's exisiting wingtips with some mods . Handles could be similar to gripper styles on the market.

So instead of making the wing area larger near the body perhaps making more area at the tips could be one answer .

I'm guessing that there would be a point of balance in such a wingtip where a pilot (with the spar's support giving some leverage) could handle the control forces required to wash the tip in and out.
Flaring into low speed flight with the help of washout wingtip discs ....dream dream....

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I've ad some fun the last few hours throwing together a few of the ideas including washout and wingtip extensions and yes reducin the aspect ratio.
The result is in the attachments.




Hate to be the bearer of bad news but Zun has already done this. The suit and in air shots look super cool but there is a reason they decided to not build and sell suits with this feature.
"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

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Id pay to watch someone reach for a hackey with those:P
Even when made in gripper style..accidently letting one go, or just letting it go to reach the hackey would throw you into a fun freestyle series for sure..




:D:D

How about elliptical wings, and calling the suit "Spitfire"?
...

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

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in reply to "Hate to be the bearer of bad news but Zun has already done this. The suit and in air shots look super cool but there is a reason they decided to not build and sell suits with this feature. "

.........................................

If all your news is that good bear away. B|
Very good to see others have already had a go at something similar.
Their suit and those shots you mentioned would be worth seeing .

Wonder what the reason/ stumbling block was that stopped their designs progress?
Do you know much about other recent experimental design concepts (outside the standard add an inch here , change a profile there, type )?


Some possible disadvantages I can see for this idea are:
* it could be uncontrollable without some structural help.
* it might be too dangerous /difficult to get the optimum dimensions worked out without a wind tunnel
* perhaps in some flight modes it could seriously harm the pilot eg bend arms back too far.
*awkward deployment procedure

The disadvantages must have outweighed the possible advantages of a greater range of flight modes and potentially enhanced control input.

I wonder if their design had a spar ?

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I think I can tell you why they killed a design like that. Same reason I killed a design with a tailwing designed similarly.

Human skeleton cannot take a surface area anywhere near that big, that far out on the ends of the limbs. It was bad on my legs- arms would be even worse.

I made a 7-foot wingsuit once with a semirigid tail surface stretching about 18" past the ends of my toes. It was technically flyable but the leverage action of the air on a surface area that big, that far out was almost enough to break my legs. Like trying to straight-arm a 60-lb anvil. It took all my strength to keep that wing open for any length of time. And when collapsed, wings that big, with the ability to exert THAT much force on the ends of your limbs are VERY difficult to control. I only flew that particular prototype 6 times. I wasn't going to survive many more attempts. It was a VERY bumpy ride. My survival was seriously in doubt every time I tried. Its a good thing I knew my true limits because a couple inches bigger and I wouldn't have survived the first flight.

Based on personal experience I'd say adding an 8-10 inch circle of surface at the wrist/outer edge of an arm would be very difficult to control, or keep spread open, but you might get away with it. Thats not much bigger than the area supported by typical grippers these days on the biggest suits. A 12-15 inch disc would be almost totally unmanageable and anything bigger than that would simply make a ragdoll of the pilot's arms. You'd be utterly helpless to control such a thing, in freefall, at arms length.

One thing those flight tests taught me thoroughly was that the future of wingsuit performance is NOT in adding vast surface areas at the very outside edges of the human body. We are simply not designed to support our own bodyweight loading at the ends of outstretched limbs.

This is also why the most successful high performance wingsuit designs these days all rely on maximizing useful loaded area down the sides of the body roughly between elbows and knees. S-Bird, X-bird, most of the taut, active wing surface is along the body and supported by the upper arms from elbows to shoulder, not out towards the edges of the wingspan.

-B
Live and learn... or die, and teach by example.

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The short answer to your questions is that it was felt to be too dangerous to market. Zun's design worked,deployment was not an issue (only if done properly), no it did not have a spar or any other rigid materials in it. While I do have the in air pictures from Zun, I do not have permission to distribute the photos here.
"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

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Sounds like you found a very real limitation there Lurch. Must have been fun jumps.
High load on the extremities with the added leverage = no go.

I'm supposing if you had such trouble with the extensions in a normal flight mode then diving and flaring such a thing into slow flight mode would be close to physically impossible without structural assistance of some kind.

Possible design solutions keep coming back to that spar / semi-rigid thingy.
My feeling is that a spar wouldn't need to take ALL the loading but merely assist. This would leave some arm/leg strength for control input as well as a variable share of the load carrying .

The wings I've been flying out a car window (nothing over 100km/hr so far ) can be very difficult to control unless the point of aerodynamic balance is found . Then they seem to lock into very smooth flight . The l.e.slats had a marked positive effect at least at the lowish test speeds . Minimal control input has big effects. If the wing gets too sideways then its injury time for me and the vehicle.

The load gets too high?
A design could allow for reducing the excessive loads either through washout control and/or sweeping the arms back . The excessive load can automatically reduce itself as the loads can be made to reduce as the wings go back.
This has been working with the smaller wings but the bigger ones are begging for a through spar . At high incidences they just blow back too quick to control easily.

In the case of your leg wing extensions perhaps a bracing bar or two along/under the legs could have helped take the extra load , transferring some of the loads to the stronger upper leg muscles or even torso thereby soaking up the levered forces and being able to make better use of the extra lift.
Perhaps one design could have you partially kneeling on the extra leg wing loads .

I'm also wondering if some sort of aerodynamic balancing is possible with an idea like your semi-rigid legwing extensions. Aerobalancing works to a degree for arm-wing extensions. If the levered forces (of the legwing extensions) were balanced by a connected forward section of the aerofoil (perhaps along the outside of the legs) similar to the rudder and elevator aero-balancing on some aircraft.

Semi-rigid (ie flexible) structural components always sound so large and heavy but these additions can be kept light weight and compact.

The limitations you have explored are not going to change in a hurry. As you say most of a fabric wingsuit has to stay within the close confines of the body's reach. Unfortunately the flight characteristics of low aspect ratio wings are also fairly limited.

I haven't done much experimenting with leg extensions (apart from filling the leg gap on my Classic2). The arm wings are proving complex enough at the moment.

Do you have any thoughts on the possibility of a leg extension acting as a well defined elevator ?
eg a semi-rigid extension that could be controlled by the feet to give up and down elevator.

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Ok tellya what:
I'll lay out a few of the practical issues I ran into when building that thing, kinda give you an idea what you're up against when trying to make tech to manipulate these forces. What stopped me wasn't the "build it and fly it" part. The reason I backed off was the combination of controlling those surfaces, struts or no struts, and making any such thing actually usable and worth its weight and complexity in performance.

Bottom line is the performance return on tail scale alone wasn't even close to worth the physical complexity and clumsiness needed to somehow nail another 5 square feet onto the tail.

And keep in mind the end was a 2nd gen hack. It barely had time to get complicated, it was as simple as an exoskeletal setup can be. First model used swimfins, fabric sewn between em, velcroed to my S-6's tail plus reinforced straps and shit. I had to walk backwards to the aircraft and hop backwards up the stairs. I dubbed this activity "Skybadiving."

Now, see, this is what happens when a hang glider gets raped by a pogo stick. You get this thing. I bounced across the sky. The fins loaded up till they sprung forward into the airflow at which point they'd recoil again. Big, wobbly airsprings.

Boing. Boing. Boioioing. I eventually got the surface to settle and functioning as "a tailwing surface" but it took such a convoluted, straining leg position to do it that it totally trashed flying the suit. "Flying" that tailwing fucked up the rest of my body position beyond belief. Best fallrate: 44. Hell, I could do THAT with a stock GTI. Pitiful.

The entire suit mod setup included zip-on armwings that went to the ankles with little spectra strut cables clipped either to the toes or to the tail extension if I was using it. The sum total wingsuit was gigantic. The armwings worked very well on their own. Used alone they delivered performance you couldn't buy in a commercial suit for another 3 years and helped balance the tail a -little- but the tail was still so far from flyable it was silly.

2nd gen was bigger and far more rigid- lexan slabs for about 3 square feet of hardwing surface and more fabric. This had snowboard bindings to spread the load and transfer it to the back of my calf. The fins version either broke my toes or put a brutal load on the top of my feet. This new version still allowed limited ankle movement but coupled most of the load to the lower legs.

It wasn't as floppy as the fins in flight and far more stable when I COULD get it to fly- but there turned out to be way more emergent effect dynamics in there than I suspected till I tried it. Changing one thing changes a whole shit ton of other things you won't see coming.

Turns out I had no idea how much flight skill and feel involves the toes until I deleted them. It totally ruined the wingsuit flying experience. All the nimbleness, gone. Effectively my legs were made out of wood. I could steer, but only by either
A: Digging in radically with one armwing, sacrificing any semblance of body position to get even a sluggish turn, or
B: Back off on the tail until I'm "flying dirty" with the tail just flapping behind me unloaded, at which point normal wingsuit characteristics dominate and I could turn something like the way I was used to. Which is a complete waste of all that wing flopping around.

It took brutal muscle strength to support armwings even close to big enough to balance that tail. And once again, I found that the muscle loads and body positions necessary to "fly a wingsuit" and "fly the tail" were not compatible and could not be made so. Straining to hold that tail out and open did bad bad things to everything else about my body position and the performance gains, although not insignificant, were not even CLOSE to enough to justify further tests.

And keep in mind by this time I'd already successfully transferred most of the load to my thighs, strongest usable muscle. Where can the structure go now? Up the abdomen? Couple it via cable/struts to the shoulders, top of the harness maybe? Great. Now your whole torso is loaded up structurally and thus partially ineffective for use as "your body." Get it? The thing about adding rigid wing structures is that it goes from "The wing is a part of your body and feels and responds like one" to a very unpleasant "Your body is part of the wing and feels and responds like it." Its brutal. Restrictive as hell. Interesting but not fun.

My next and last tests were a wingsuit developed from scratch to test certain design elements related to the internally strut-braced wingsuit concept. This wingsuit was well known and somewhat notorious due to its outlandish construction and appearance: The Hardcase. It was so wild looking nobody noticed its technical complexity.

Made starting from a 40 year old hard leather biker jacket and a bucket of spectra line this suit is... bizarre.
And it looked fucking cool as HELL.

What got no attention at all was that it incorporated about a dozen unique/original wingsuit design bits. Miniaturized 3-ring release cutaways built into the zippers. 2-piece construction, wingpants and jacket. An emergency "nimbleness" cutaway that could sever the entire suit at the waist granting instant freedom of movement. Structural elements put together with spectra lacings like buckskin clothing. And much much more.

Variable wingspan, relocatable wing attachment points and an adjustable harness made mostly of braided nylon webbing integrated into the suit. So by harness tweaks you could set exactly HOW far you can stretch your toes and HOW far you can spread your wings until they're tight.

You know what I got? The worlds most restrictive wingsuit. It was like a flying bondage fetish experiment gone bad. It flew just fine and delivered average performance comparable to other suits of its size, but wearing it and flying it were excruciating.

You know what happens when you transfer wing load via harness? It goes SOMEWHERE ELSE. Somewhere uncomfortable. It proved that I could set up a suit designed around a certain body position and braced internally to optimize and hold that position. It also proved that such a setup is inherently restricting as all hell. Your arms need to be just -so- for that strut effect to work.

So while its working you're tightly restricted to whatever body position makes the strut shape. Design the suit around the body position AND the strut shape and you've just frozen yourself in place. Anytime you're NOT in ideal strutshape for that suit you're falling out of the sky like a rock instead. There is very little middle ground.

It can be made to work but the tradeoff is you can barely move. Suit gets bigger, start adding exoskeletals back into the mix and it only gets much worse real fast. This is why pretty much everyone else who has ever tried to pull off this effect is dead. They went straight from "don't know shit" to "beyond controllable" in one step. I did it real gradual, snuck up on it like, and lived. Turned out not to be worth the effort except for the stuff I learned.

Several years more development of this would result in a wingsuit that weighs 20 lb, has all kinds of struts and joints and hinges and tech tricks to make it easy to use like flip-up fins and quick releases, flies like a lip full of novocain, carries 10X the risk of a standard wingsuit, and gets you... a whopping 10 mph better fallrate than you could get with a ram air suit 200X simpler and safer and infinitely more fun to fly.

Relative to "how much more" you can get vs the amount of risk and complexity needed to make it happen a certain way, exoskeletals are not worth the effort or the risk.

This thing was SIMPLE as such concepts go yet the mechanical complexity and interplay needed just to tack on that tail surface were ridiculous. With the tail I had to execute an elaborate 28-step airborne-Houdini post deployment sequence to get that thing off my feet and secured for landing, hung off my chest strap. I was deploying at 4500-5000 feet and it took me at least 1000 to deal with the goddamn tail. Lemme tellya: You ever thought about just how difficult it is to take snowboard bindings off your feet under canopy? All that risk and complexity just for a simple area hack that barely flew for shit.

Anything you build and test must be compatible with existing skydiving equipment: Can you get a pilot chute around this thing? Can you control it if one side fails or suddenly catches wind, flips inside out and gets pinned that way? What if you fatigue out and can't control it at full strength, is it going to kill you? Mine would have, and it was still so small it was lightyears away from being landable or even repeatably easily flyable at all. If I'd lost control of that thing I would have wound up in the mother of all unrecoverable flatspins. Odds of survival would be very, very low. The lesson is that making wings bigger than muscles can EASILY handle ESPECIALLY outside the skeleton's natural reach gets infinitely more lethal with every inch you add.

You start fucking around in this territory you are up against something like a 97% fatality rate.

You exit the plane with big rigid shit strapped to you, you better be SURE. If you don't get it right, you are dead. No time no negotiation no appeal no parole. Game over in one shot. If it isn't close enough to what you already know how to handle, again, you are dead. Immediately.

This is why I haven't built more stuff. I got the answer I was looking for. It wasn't the answer I wanted or hoped for but it was an answer you can only learn by doing. The answer was that trying to distort wingsuit flight too far from what it is now, destroys the experience. You tack on anything bigger than your skeleton and that part of your airframe goes numb and radically reduces the abilities of the limb it is attached to. So much so that it isn't worth it. Not even close.

I could have added rigid armwings. Small enough to be controllable, big enough to be effective. I'd already proven to myself that I could effectively design and build such a thing since the tailwing technically "worked" just fine. Then I would have had numb arms AND numb legs. World's biggest, clunkiest wingsuit with piss poor performance and wooden feel. Yuck. Those experiments took me places alright, places it turned out I didn't want to bother going to. I finally reached the conclusion that a device already exists to perform that 30-0 mph part of a flight.
A canopy.
-B

This is something people like Giselle don't want to hear. She made a lot of la-la-la noises trying to drown out and not hear the fact that I've done what she's making noise about-fabricated this kind of gear from scratch and test jumped it to find out how do-able it really is. I was disappointed. Making it wasn't as hard as I thought. Get far enough into making it WORK and you'll either evolve into Yves Rossy's carbon wing or a canopy. Neither is a wingsuit.
Live and learn... or die, and teach by example.

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Now, see, this is what happens when a hang glider gets raped by a pogo stick. You get this thing. I bounced across the sky. The fins loaded up till they sprung forward into the airflow at which point they'd recoil again. Big, wobbly airsprings.

Boing. Boing. Boioioing.



The mental image of this had me in hysterics. Reminded me of the sky car: http://www.aerofiles.com/pitts-skycar-filmclip.jpg

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Gday Lurch,

That was the most interesting and informative post .
Congratulation's on your test pilot and design efforts , especially the test pilot bit. B|
If they haven't already ,your test flights should be recorded in a history of wingsuit development, with photos hopefully.
Then we won't have to reinvent your wheel .

All the design and flight issues you have highlighted are noted , realised and extreme .
The possibility of an upside down spin with one wing extended and the other crumpled further powered by an uncontrollable leg wing extension throwing the pilot into high g spasms has occurred to me:D

Slightly more cautiously than you, I'm taking this real easy and careful like. Just like a little mouse nibbling on a rat trap.... And I know it's a trap.
The bait , good flight performance gains, is still alluring.

A major design issue is definitely to keep it all easily controllable and intuitive and yes this makes it all potentially very aerodynamically complex.
I'm finding the design process to be much more about feeling into it than mathematics . Trial and error laced with experience and intuition is working so far .
I like what you said how it would only fly ok in one position and that this made it very restricting and unfun. Noted.

During my tests , I found I could increase the extended arm wings comfortable flight range ( at a cautious 100km/hr) just by altering the L.E section.
A more rounded L.E. resulted in a wider range of comfortable movement and controllability of incidence and sweep. However with a sharper LE. the wing seemed to fly in its narrower range noticeably cleaner .

The addition of the l.e. slats seemed to make the armwing more controllable over a wider range of movement.

My first efforts went form barely controllable to easily stretched out and flown within a reasonable range of movement.
Of course too much incidence at too high a speed and the wings will still blow back .

Now (after a few changes ) at high incidences I can feel when its about to go and can reduce the incidence or sweep my arms back a bit thereby reducing the flight loads to more easily controllable.

Variable camber via T.E.flaps are next in line aiming to further improve the low speed range of flyability of these wings.
So far control improvements have been sufficient to keep leading me on to the next step.

Is it all worth it when wingsuits fly ok anyway and we have parachutes for slow flight.?


It seems to me that flying wingsuits at their maximum performance levels can leave the body in a very rigid and uncomfortable state. Personally I wouldn't mind if the Ws got a bit rigid if it meant that I could fly at maximum and minimum and stay in a relatively relaxed body position.

The miriad of possible designs and engineering solutions may be a can 'o worms, and the solutions may not be immediately obvious, but that doesn't mean there's no solution to the issues you've raised so clearly.

in reply to "You start fucking around in this territory you are up against something like a 97% fatality rate. "

And loving it :D
This is a VERY real design challenge and that is what keeps it interesting for me.

After you sharing your experiences I'll be keeping the extra leg wing area very low to start with.
And it'll initially be in 1/3 scale so no-one should get hurt .
:)

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:)You shoulda seen the clownwalk it took to get to the plane. Walking backwards, in flippers, with the flippers tied together by a tail's width of fabric. Was way too complicated a pain in the ass to try to put it on and gear checked IN the plane.
Live and learn... or die, and teach by example.

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I looked over your pics.

Then I put some thought into the thought processes YOU must be using to produce this stuff and where you think you're going with it.

Your approach to this may have some potential. If you dial in your forces beforehand as it looks like you're trying to do the resulting hardware should at least be a lot more refined than mine was by the time you build it.

I will tell you what I can if it will help you.

Looks like you've got a lot more patience than I did. Every time I built shit I rather brutally forced the object into existence. I knew nothing of sewing. I did that shit with a 50$ portable sewing machine and a bunch of handheld hole punching tools. Broke a million needles before figuring out a crude modular laced construction method that was fast, semi-accurate, and most importantly, indestructible.

Build a wingsuit like a buckskin wallet out of 550 spectra line and you could use the suit to tow a truck. Looks like shit, but if you tie off the spectra with a dozen layered surgeons knots using fucking vise grips, guess what: It won't fail. Knots that big DO get fuzzy, though.

I think you're on the right track with feeling your way through it with the hardware. I spent far more time refining the armwings than the tail as soon as it became apparent which line of inquiry was going to deliver more results more usably.

The big version was a successful use of strut and sail effects. Put simply I had zip-on singleskin wings going from the wrist and trailing edge of a Birdman S-6 all the way to the ankles. The wing ended squared off about 4 inches out, with a line from there to the toe.

In practice this worked even more awesomely than I thought it was gonna. Back off on the wings and fly dirty in a flock and the wing just goes limp, folds back out of the way and flutters a little. NO dramatic effects on flyability at ALL. Slightly bumpier due to more loose fabric if you weren't maxed out, but I could still dock cleanly in a flock with it.

Max out with the suit and then deliberately pull the little lines taut with your toes, and half the suit turns into a giant angled sail. I flew it once at a major event. Theres a thread around here somewhere. It created a minor buzz when seen in public.

I put maybe 70-100 flights on that configuration. Any time I didn't want the wing or complexity, just unzip it, unclip the toecables and the S-6 returned to stock. In time I kept the zipons tucked in a wing pocket as a sort of instant zipon supercharger anytime I wanted a 3.5 minute solo flight.

It became basically a daily driver utility option for that suit until the Tony S-bird came out and I won one in a raffle. I eventually cut the wing back to a triangle and deleted the toecables. The thing about the toecables is, fuck up the deployment and you can toss a pilot chute through the loop. The suit was a horseshoe mal waiting to happen. Extremely unlikely, but very, very possible.

So flying that hack created a permanent need for extremely careful and deliberate deployment management. To make matters worse that suit had a tendency to make you go head-low during deployment with the wings folded because of all the loose fabric below the waistline which is exactly what you DON'T want if you're trying to keep the pilot chute away from your feet, so it was VERY tricky to fly and always made me nervous. The S and X bird suits were the first suits to hit the market that beat the performance I could get out of that hack. So when I got one, I retired the hack. I still keep it as a backup suit.

Heres where I kinda disagree with you about max flight though: If you're doing it right, its actually not that tense, or locked in position, flying the ram-air S-Bird I use as a daily driver.

So far, Although it took years of straining in the wrong directions to learn it, the longest flights I've had are ones where I sort of "got the feel" just right and relaxed in a very specific, certain way. I've had flights of 3:15 where I was shaking like a leaf after, because I was trying way too hard and flying it all wrong.

End of last season I set a new best of 3:57 while flying with a vicious leg cramp. I was laid out wide and flat and "sprawled out" the way a suit the size of an S lets you do, while mostly focussed on trying to relax that damn cramp or at least keep the cramp managed enough that the leg doesn't lock or fold on me entirely.

I was distracted as all hell, thought I'd already blown the time attempt and just spent the whole flight staying as sprawled as I could while trying to relax that one muscle while still keeping my legs out and toes pointed. I wasn't overthinking the "max out the suit" thing. I didn't think I'd beaten my own record until I watched the video after I landed. Because I was distracted I wasn't trying too hard, and I wasn't even all that fatigued out after that flight nor was I shaking or experiencing any extreme muscle fatigue. And this was with an off-the-shelf factory Tony suit. The most effective body position, I didn't feel strained, I was just sort of cruising around easy while trying to manage that cramp.

Within the "max-performance envelope" of flying like that, it doesn't FEEL rigid or restricted at all. If I pull in a wing I know I'll start to drop faster but the expectation and relationship are very instinctive and very linear. There are a number of "enhanced performance ninja moves" that are somewhat rigid but they're not the only way to get long glide and slow fall out of a suit. Theres what feels like an infinite variety of variations on body positions that have various effects on "max". Because the suit is totally "fluid", you get exactly as much wingsuit action as you feel like engaging and know how to do, controlled by how far out your arms and legs are, and how good you are at fine tuning a rather "general" working body position.

With rigid surfaces, control is binary. It is either snapped into place and flying or it is tearing your arm off.

A wingsuit can smoothly transition from maxed out to gradually curled up in a ball and not flying without any major abrupt transitions. I was betting on my understanding of this relationship when I tested the lexan stuff. My worst case scenario: curl into fetal position with armwings spread wide and pull legs in to belly... basically sit on the wing in freefall and dominate it with the armwings. This trick got me out of lesser spins in a single snap roll, is useful for regaining control of flopping rodeo passengers, and I figured if that approach to managing a floppy object attached to me works with something as big and draggy as a passenger it ought to work to keep control of a lesser slablike surface. It did. When it got too hard to handle I could just scrunch up and keep flying it anyway.

Point is if you want your concept to work and keep the flight feel you're going to need to make your hard surfaces articulated and flexible enough not to significantly impede the movement of the wearer.

Let the wearer decide the shape and just shape the surface so its ideal, at the most comfortable flying position of the suit you wish it to be a part of.

This is why the superhard ram air suits work as well as they do. Since they take their own shape they tend to self-optimize but still allow fluid movement. So essentially what you're trying to do is pull off a functioning substitute for the wingsuit ram air effect with hard surfaces.

Think scaled armor. Overlapping plates. So that the wingshape just smoothly stops being wingshape and ceases to exist the further back you bring your arm. If you design this right, you won't need to worry about it buckling because if the strain got that high you'd just bring your arm in a little since you couldn't hold it out against that wind anyway.

Looks like your initial modeling approach lends itself well to being made in such a way.

In fact your "out the car window" tests would be very good for this:
Heres my suggestion: Right now your results are very binary. Either it is in a narrow working range or it ragdolls your arm against the side of the car. It will do this in flight.

What you need is the same thing that makes a wingsuit so fluidly controllable: Segment it so you can just pull your arm in. In practice the result you're looking for is the ability to not just "turn it off" but modulate it. Only extend it halfway and its halfway effective without restricting your range of motion or ability to extend or retract the arm.

In practice, making this shape real, strong, snag resistant and effective will be very difficult but CAN be done.
What are you using for materials in your models, and what materials would you plan to make a real one out of? Your model looks like some kind of light .010 maybe .015, .020 plastic? The trouble with modeling that way is you spend a lot of time solving construction and materials problems that only approximate or just don't apply to any attempt at a real working model.

I strongly suggest next model is made of thin sheet lexan. My tail was made of heavy .220 lexan which was ridiculous overkill but typical of the way I build brute force physics hacks. The structures you've made, if made of lexan half that thick simply will not buckle. They'd bend into a U shape under tremendous strain but to date I have never succeeded in loading lexan to a permanent crumple failure like what happened to your wing there. If you made your zigzag wing structure of sheet lexan you'd have to jump up and down on it to even stress it.

The machine screws you used to tack it together will shear, but the lexan won't permanently deform unless you drive a screw into it and focus tonnage on a single point. You CAN make lexan crack if you use it wrong or rip the screws through the material. You would have to ditch the panhead machine screws you're using and predrill holes about .010-.015 bigger than your fasteners to allow for metal expansion without cracking the lexan, use stainless buttonhead cap screws and locknuts inside. A wing made that way, you could beat it with a 12-lb sledgehammer without seriously damaging it.
And its light...

Legal Afterword To Cover My Ass: Anything and everything I say here can and may be inaccurate, and almost certainly will. Any attempt to construct and fly any device based on any advice I may offer here is regarded as suicidal, stupid beyond belief, and is extremely likely to result in death or disability. In essence, everything and anything I say about wingsuit design and construction, if you follow it and do it all right, you're still going to fucking die instantly so do not even think about it. Some, most or all of what I say is or may be purely for comic/entertainment purposes with no obvious indicators as to whether there is any fact in any of it. Building actual flight hardware of any kind is done 100% at your own risk. Building and flying anything based on information some idiot put up on the internet would be a phenomenally stupid thing to do, guaranteed to result in your death. Do not do it.
Live and learn... or die, and teach by example.

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B|

Every point you've raised is totally specific to design issues I'm having. Much food for thought , cheers.

As for flyability ie ease of use:
I'm finding this is largely where the work is. It would be relatively easy to make a rigid wingsuit locked in one shape, might even be fun one day . As a non-rigid internally piloted design right from the start , my design won't evolve into Rossy's or Skyray's solid wing. Not too keen on flying under a separate wing myself I'd prefer to be inside the wing and part of it.

I'm concentrating on the arm wings as I feel that is where the major gains are to be had.
Basic idea is to copy from the arm's structure but allow for enhanced load carrying via articulated spar/wing. The skinning takes a fair portion of the load as well.
The whole arm wing/spar/skinning set up is based loosely on the leaf spring principle. As more load goes on more structure kicks in to support it. Plus the wing and spar get thicker/stronger towards the body.

I've found balance points for the wrist and elbow where control input and load carrying are minimised.
More work to do final placement/shape of the shoulder pivot where it attaches to the torso plates. I'm thinking this wont be resolved until full size 'back of truck' flying tests.

I'm thinking these wings can work with a standard fabric torso and leg wing , simplyfying the development and testing process. My V2 lives in danger of being chopped up a bit.
I'm also considering having sailcloth upper arm sections to further simplify the development process.

Hearing how well your single skin arm wing extensions worked in different flight modes was enlightening.

I guess the leg wing extensions on your design pushed the centre of lift back a fair bit causing strong pitch down. You mentioned you had trouble balancing this with the arm wings.
This is one issue I'm expecting to arise with my swing wing design and its variable CoL. I'm hoping to counter/balance the CoL variance with extra forward surface area controlled by upper shoulders and head neck orientation(aerohelm).
Or it may not be a problem eg sweep arms back, get in major dive. head up flattens it as bit allowing some wing extension for further manouvering.


dangerous uncontrollability problems obvious.

I know all this talk of plates and spars and skinning makes it sound rigid and unbending but the design and materials being used allow for good flexibility . Finding torsion axis and balance and pivot points is all part of the design/test process..
.
Of course with your flight results in mind I'm aware early efforts may be too physically (and mentally?)restricting. The arm wings are twistable bendy things even though they might look as stiff as glass . They move easily in a wide range of movement with no load and the tests are so far positive that they will in the air as well.

Your lexan and SS panhead recommendation is noted and welcome.
I'm using hardware store polycarbonate sheeting (0.8 mm) mainly cause its cheap and readily available. Same with the cheap screws. I'm looking forward to using better materials once the design matures a bit.

I found that I could bounnce my sledge hammer of a poly sheeted foam inner wing section without barely a mark and no permanent deformation.
The poly skinning I'm using will crease however under high loads without some sort of spar / reinforcement. Thicker poly ? the extra weight puts me off a bit.
However if the skinning was made of a higher quality material then the spar could be dispensed with using the skinning as the load carrying component.

I hope I can achieve your level of indestructibility . I'm pretty good at breaking things.:D
I wasn't gunna give up until I really broke something.
Now I'm thinking glueing AND screwing with some integrated carbon rods in high load areas.

Do you know if lexan be glued good? and heat folded. (I'm off to see the plastic wizards.)

Gotta go with your disclaimer
Legal Afterword To Cover My Ass: Anything and everything I say here can and may be inaccurate, and almost certainly will. Any attempt to construct and fly any device based on any advice I may offer here is regarded as suicidal, stupid beyond belief, and is extremely likely to result in death or disability. In essence, everything and anything I say about wingsuit design and construction, if you follow it and do it all right, you're still going to fucking die instantly so do not even think about it. Some, most or all of what I say is or may be purely for comic/entertainment purposes with no obvious indicators as to whether there is any fact in any of it. Building actual flight hardware of any kind is done 100% at your own risk. Building and flying anything based on information some idiot put up on the internet would be a phenomenally stupid thing to do, guaranteed to result in your death. Do not do it.

Ditto for me

:D

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in reply to "In practice, making this shape real, strong, snag resistant and effective will be very difficult but CAN be done.
What are you using for materials in your models, and what materials would you plan to make a real one out of? Your model looks like some kind of light .010 maybe .015, .020 plastic? The trouble with modeling that way is you spend a lot of time solving construction and materials problems that only approximate or just don't apply to any attempt at a real working model. "

..............................................

Yes it can be done!:D

The full size version does indeed pin-point some design difficulties not immediately apparent with the models as you've suggested.

The design of the fore-arm wings has solidified a bit (pun intended) . They feel good to move around in .
However thewings pictured are only the outer wings of a larger system , needing a thru-spar and inner wings in order to function as designed.

The through-spar linking the wings is not finalised . Current version works but feels clunky and uncomfortable. Needs better placement of the shoulder hinges and more padding.


Currently the design has the forearm wings retracting on the front side of the body mainly to avoid the rig .

When folded the wings still present a fair surface to the air.
I'm hoping the folded wing position will respond to normal tracking position inputs. Thats gunna be difficult to test without jumping it.. and having some wing locking device to keep them closed until they pass.

Stumbling block is emergency access to handles,
The E.P. issue is less getting at the handles which are clear and accessible , more about removing the forearms from the wing.

To maximise wing efficiency the l.e.'s enclose the fore-arms. This means a more consistent aerofoil shape can be achieved but creates issues with arm removal.
The option of using an open slot in the wing for the arm creates construction and strength issues as well as reducing the wing's efficiency but would allow easy arm removal.

Currently wings need to be retracted before arms can be removed easily.
Perhaps some sort of back up break-out opening along the l.e. sleeve would give some options in an emergency.

Next design priority is the thru- spar.
I'm close with the dimensions and workability but the materials have to change.
Polycarbonate was looking too heavy and complicated for the inner wing spars. I'm thinking two sections of carbon fibre fishing rod and alum hinges will do the job of a mess of polycarb.

:)

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in reply to "How about creating a hole for the hands/arms, and covering it with 2 patches of rubber. Effectively creating a slit thats closed, but allows a hand to be pushed though?"
.....................................

Thanx for the feedback .
A rubber covered entry/escape slot could work.

The fore-arm wings are easy enough to get into when folded sort of like reaching for your ankles in a tracking position. Doing this easily in the air may be another thing.

Another issue I'm having is designing a locking device to keep the wings closed until both arms are fully in the wings and on the wing-tip handles....and whether the wings should be locked closed again in flight prior to deployment.

Any constructive thoughts welcome.
cheers

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