yuri_base

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Everything posted by yuri_base

  1. Here's an illustration of cocoon hesitation leading to line twists and harder than normal opening, vs. exposed slider opening leading to immediate (but not hard), properly staged opening, with no useless altitude loss while trailing the dancing cocoon (dt=1/15s (2 frames at 30fps) is the step between frames (0.15s is a typo), 0.6s for the last frame): [inline CocoonHesitationVsExposedSlider.jpg] Note that the 1st thing that shows up when D-bag opens is yellow on the left (this is tail/cocoon, center cell is yellow) and red on the right (this is the slider), and slider is instantly inflated and quartered - this is what we want! Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  2. >>> steady state means GR and L/D are equal
  3. Consolidating old knowledge - how to subtract wind: How to measure true L/D on a balloon jump How to calculate true airspeed on a plane jump Does anyone even try to subtract wind from their GPS data? (note that in those prehistoric times before WSE, I myself oftentimes confused GR and L/D, a common confusion that most jumpers have even today) Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  4. >>> Anyway, I tried your method of leaving the slider grommets fully exposed. I did 7 WS jumps today and tried it on all of them. I dident notice any difference from how I normally pack. It dident open any faster from what I could tell and it certainly dident open any more on heading than it normally does (which is usually not on heading at all).
  5. Slider is actually much easier to control when grommets are exposed. Just keep pushing the grommets all the way by reaching them with fingers while closing the flap with the first rubber band. They are not going anywhere. Again, this disclaimer applies: Another side benefit of this pack job is that it saves, perhaps, a couple of hundred of feet of unnecessary towing of the cocoon, as the opening is more "definite", immediate - you "fall" on the inflated slider, so the initial tug on the shoulders, before main inflation starts, is more definite. Not hard, just more "concrete". Many people died because they didn't have those couple of hundred of feet, because they were unnecessarily "falling into pillows" on opening. And another benefit is heading performance. When you fall on a quartered, inflated slider, it sets the firm heading which is maintained through the opening as long as the steering through the opening is even. And another benefit is no linetwists. Like... gone! Because canopy doesn't have time to spin around as a dancing cocoon. I've been packing like this for years and hundreds of jumps (before switching to skydiving my BASE canopy full time), it works like a charm. First shared it 5 years ago, no one is interested. It's ok, I'm used to it. People need The Authority (John le Blanc, Brian Germain, etc.) to tell them something, not some random guy, and not their own logical thinking. PS. The video of cocoon hesitation above is from 2009, me flying in Phantom-1. That's when I had the 'Eureka!' moment, and started packing with slider exposed. BOOM! Problem solved. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  6. By the way, this is a monotonic function of L/D, so that the higher L/D, the higher the lift. So, if higher L/D is achieved with a smaller suit/system, this smaller suit will have more lift than a big mattress! Paradoxical, but absolutely true. Ahhh, when you say L/D you aren't actually talking about the airfoil shape lift coefficient. You're talking about experimental overall L/D. Right? Yep. No, not interested, have absolutely no need in this. It's just a way to slow thing down. One doesn't need to do years of schooling and tens, hundreds of thousands of $$$ to cut some foam wings. I've already spent way too much of my life in academia. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  7. By the way, this is a monotonic function of L/D, so that the higher L/D, the higher the lift. So, if higher L/D is achieved with a smaller suit/system, this smaller suit will have more lift than a big mattress! Paradoxical, but absolutely true. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  8. Increase in L/D has value by itself, regardless of what surface area is doing. We don't have to extend the trailing edge of the leg wing past feet. Suits also didn't have extended leg wings right from the start. It may come later, in the process of experimentation. That's not true. Half-WS is very, very fast. In fact, so fast that fully braking (in boxman position) for 5 seconds is not enough, I get hard openings (on my BASE canopy) from residual speed. WS/2 is faster than WS because arms are not sticking out to the sides, and L/D is naturally closer to optimal 1.4 when there's optimal balance between the component of gravity along the flight path ("gravitational thrust") and the projection of the total speed on the ground, resulting in max Vx possible. If Area is decreased more than L/D is increased the wing will generate less lift. That is a fact. Arm wing tension. WS/2 Prove it. You have said multiple times that it will be faster. Show me Vx data that back that up. Also show me distance traveled. Lift in sustained flight is only determined by weight and L/D, per formula L = W*(L/D)/sqrt(1 + (L/D)^2) which is absolutely correct, unless one denies Pythagorean theorem. I'm poor with documenting my adventures. So, I might not have GPS data for WS/2 (in general, I gave up on the idea of using GPS for flight analysis, it's mostly useless, other than windless BASE jumps). I did jump with L/D Vario running on LG G Watch R, in Lodi ca. 2015, in half-V4, and measured L/D as about 1.5-1.6, but 1) L/D Vario doesn't have data recorder yet, 2) I was without camera, 3) I was mostly interested in seeing if I can achieve L/D of about 2.0 in 'Superman' body position (with one or both arms stretched forward). The multiple experiments with Superman showed that either I need bigger leg wing (V-4's is not that big as of modern mattresses), or stronger body (alas, I'm not strong, with beer belly and all) to maintain perfect 'plank' (I was more like a banana). But no one should doubt that when (the question is not if, but when) WS/2 will be officially introduced by mainstream WSMs with great aplomb and fanfare, it will be touted as a speed demon, the fastest flying human machine, and the graphs with Vx will start popping out on Paralog and Skyderby, then everybody will see. And praise their gods, WSMs, for such ingenuity! While it's been done long time ago, and was not even done secretly. (I've jumped in Eloy, Perris, San Diego, Lodi, etc., with half-Phantom1, half-V2, and half-V4). And is as trivial as finding an old suit and cutting arm wings off completely. But WSMs could have designed wingsuits with fully detachable arm wings, then we get 2-in-1, two flying machines in one! Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  9. That's what I'm trying to do here. But so far, absolutely no one is interested. Which only proves how deep the CoW swamp is. People have been conditioned over the years by facebooks to which they've migrated from specialized forums like this one to not think and aspire, their brains turned into a one big Like button. All they can do is to react to yet another notification from facegramitter, and OBEY. That's why they're not thinking critically of the current situation in WSI, and they have no enthusiasm to build something better. The ideas I've already brought to life (such as WS instrumentation, WSE, WS theory, flight analysis and modeling, half-WS, etc.) or am proposing for the joint ("blockchain") effort ('The Machine') have universal value by themselves, the messenger and their personality and method of communication do not. Ideas have their own life. I'm offering ideas, not myself. Strong minds won't be turned off by some rhetoric, they will jump on the ideas and bring them to fruition for everyone's benefit. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  10. Increase in L/D has value by itself, regardless of what surface area is doing. We don't have to extend the trailing edge of the leg wing past feet. Suits also didn't have extended leg wings right from the start. It may come later, in the process of experimentation. That's not true. Half-WS is very, very fast. In fact, so fast that fully braking (in boxman position) for 5 seconds is not enough, I get hard openings (on my BASE canopy) from residual speed. WS/2 is faster than WS because arms are not sticking out to the sides, and L/D is naturally closer to optimal 1.4 when there's optimal balance between the component of gravity along the flight path ("gravitational thrust") and the projection of the total speed on the ground, resulting in max Vx possible. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  11. Ooops, the times should be multiplied by 10: 0.2s, 0.4s, 0.6s, and 1.33s. My math is terrible. 6 frames at 30fps is 200ms, not 20! Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  12. That doesn't mean that it doesn't need to be addressed. It won't move by itself, push the grommets all the way up the lines while folding and closing the bag. Yuri, you should know better than to try to dish out a slider-out packing method to a beginner over the internet. I'm not talking to anyone in particular, the thread is read by hundreds of people of all experience levels, and the info I'm sharing is universal. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  13. Here's simulated pressure distribution over NACA 0012 airfoil at 30m/s: [inline SimulatedPressureDistribution30ms.png] So, it's about 90Pa difference on the trailing edge. We fly faster than 30m/s, let's say, 45m/s, so pressure will be around 200Pa. That's only 2 grams of force per square centimeter. Imagine trailing edge 1m long, 1cm wide, and a 1m steel ruler weighing 200 grams is put on the trailing edge. With firm enough foam and tension applied to the trailing binding tape, 200 grams are nothing to support. So, shouldn't be a problem at all. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  14. Here's an illustration of cocoon hesitation. Yellow is center cell (tail wrap), cells get orange and red progressively towards the end cells; slider is red. t = 0 - canopy is out of the D-bag: [inline CocoonHesitation000.jpg] t = 20ms - cocoon is now open on the top (facing the sky), but closed on the bottom surface (facing the ground), as the relative wind hits it from the bottom at an angle due to canopy sagging below the wind line due to weight: [inline CocoonHesitation020.jpg] t = 40ms - cocoon is dancing still partially closed, slider possibly being shaken down the lines, still hidden by cocoon's tip: [inline CocoonHesitation040.jpg] t = 60ms - cocoon is still dancing, slider still not visible: [inline CocoonHesitation060.jpg] (unfortunately, cocoon goes out of frame, but it obviously doesn't look pretty out there) t = 133ms - cocoon is finally unwrapped, red slider is visible and inflated, but probably moved down the lines a bit due to shaking, and the canopy managed to make a full turn during the dance - hello, linetwists: [inline CocoonHesitation133.jpg] Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  15. See my reply above. Why would anyone let the grommets move down, is it like they have this insane sliding power that the packer can't overcome? (Never happened to me while doing hundreds of jumps on this pack job.) The wrap on the tail helps with keeping grommets up during packing (not required, since grommets can be controlled all the way through closing the bag), but doesn't prevent them from sliding down under the cover of the cocoon. It tuns out (watch video attached in my post above), the cocoon - especially on WS jumps - likes to dance closed in the wind, just that extra fraction of a second, but that dance is what causes the slider to move down the lines, as well as spin the canopy around. This may not be noticeable on new, super slippery ZP, but as it gets more used, the cocoon is just happy to dance, because in WS deployment, the wind hits the cocoon from the bottom, which is wrapped by the tail and is a smooth surface. So, a small hole in the apex of the wrap is not sufficient - I tried that; it needs to be big, such as when slider is exposed. The most important thing in reefing the canopy to prevent hard openings is to let the slider be the first thing that "sees" the relative wind, and gets pushed against the stops for good. The worst thing to do is to "hide" the slider from relative wind, under the cocoon. As in wingsuits, acceptance of new things and brave thinking in skydiving/BASE is very slow. Most people just do what most other people do, copying others mechanically. They don't think through how, for example, opening actually works. And they are scared of any deviations from "official party line". Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  16. If even just one dude in the world builds a wing system with L/D = 3.6 (20% improvement) and opens one of many big WS BASE jumps in the 1500-3000m+ range that are impossible with the current L/D = 3.0 (because of nowhere to land, or reachable LZ being within national park or wilderness - Mount Whitney comes to mind, that's potentially an almost 10000ft jump if one can fly all the way to the valley), that's 0.6km extra for 1km of altitude - then it'll be like a solar eclipse when all birds suddenly stop chirping, same will happen to all naysayers. And it will be silly and comical to not to admit that this system is a great achievement. The Stooges will, of course, not admit it and will try to look unimpressed and keep their cool. This will only make it more comical and make them look like Dumb & Dumber. Same as comical situation these days when they've never used L/D instrumentation available for years now, and they never built a new class of flying gear - half-wingsuit - which some dude was openly doing for years at different DZs, and they saw it and even took pics of it. What can I say... Stooges are such stooges. One can only laugh and shake head. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  17. Sure it will always suck, but it will suck less. Here, we have approx. 3:1 aspect ratio for the arm wing (tip to tip) and about 1.5-2:1 for the leg wing. Vs. 0.5-0.7:1 for one "flying squirrel" wing. Any aerodynamicist will take 3:1 wing over 0.5:1 any day! We need to build it to find out. We can't just dismiss it outright. Small wings do generate lift, somehow my Prodigy and my Phantom-1 supported 260lbs of this meatbomb for hundreds of flights... Of course they will provide lift. They will However provide less lift. Any inovation in sutes needs to me wildly applicable and increase lift. You need to be able to fill a plane with them before you can claim you revolutionized the market. In your picture how are you going to support the trailing edge? We don't need to fill the planes and we don't need to revolutionize the market, we need to revolutionize the wingsuit design and push the limits of performance. We don't need anyone's approval or market share. What we do need is L/D of at least 3.3. Whether a large number of such wing systems is built in mass production or just 5 built by enthusiasts, doesn't matter if we're able to achieve higher performance than what's achievable by mattresses. And anyone can build one for 200 bucks or less. The trailing edge actually doesn't get that much of pressure differential: [inline AirfoilPressureDistribution.jpg] That's why in inflatable suits, where the surface area gets smaller and smaller towards trailing edge, the internal pressure, with the aid of mild stretching by arms and legs, is sufficient to support the edge. Same with foam wing: foam firmness + stretching of the trailing edge (which will be finished as a stitch on the wrapping fabric) should be sufficient. We can probably even extend the trailing edge of the leg wing past the feet, as in mattresses. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  18. That doesn't mean that it doesn't need to be addressed. It won't move by itself, push the grommets all the way up the lines while folding and closing the bag. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  19. Sure it will always suck, but it will suck less. Here, we have approx. 3:1 aspect ratio for the arm wing (tip to tip) and about 1.5-2:1 for the leg wing. Vs. 0.5-0.7:1 for one "flying squirrel" wing. Any aerodynamicist will take 3:1 wing over 0.5:1 any day! [inline SurfaceAreaReduction.png] We need to build it to find out. We can't just dismiss it outright. Small wings do generate lift, somehow my Prodigy and my Phantom-1 supported 260lbs of this meatbomb for hundreds of flights... Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  20. It's funny when you look at mainstream WSMs' web sites and facebooks, and understand what's really going on, how they are all proclaiming great victories at competitions, always taking gold! Every one of them, always, takes gold, wins 1st place! ("LOOK AT US!!!") There's enough competitions and sub-disciplines in them, and only 3 main WSMs that they can always cherry-pick the one where they won. This creates the impression - for the weak-minded - that they are cutting edge in WS R&D, they achieved huge progress! Well, if one analyzed the results, year to year, you will see that the absolute results are not really improving that much, and most of them can be chalked up to the ever increasing pilot skill, not to actual improvements in wingsuit performance. It's all just the same WSMs reshuffling in the tables of fluctuating results, but they can always pick one where they won. It's all just Brownian motion, where one or the other molecule will "jump" higher than some other. Same with R&D. "Oh look at our pretty 3D-model of a wing on computer screen! [It's still an atrocious 0.5 aspect ratio, and the profile in flight of a cloth wing is severely distorted anyway.] Look at our smooth leading edge! [It's still too blunt to have a nice airfoil, we need leading edge extending 5, even more inches forward!] Look at our Michelin-like track suit! [I'm still waiting, 13 years later, for any WSM to release the new class of flying gear, based on a trivial idea - wingsuit without arm wings, half-wingsuit, WS/2, speed demon, with optimal L/D~1.4 for fastest speed.] Look at all our videos, with all cool/hardcore flying! [Most of it is possible even with old suits of 10-15 years ago; the rest is an automagic consequence of sewing bigger body mattresses. Patrick de Gayardon, if he stayed alive, probably could have compressed the whole 20 years of small->big progression in just a couple of years.]" It's all bluff. It's all BS. It's all Godzilla Marketing. It's all egos and #lookatme's. It's all just brownian noise. MWGA! Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  21. High L/D is not only important for long flights; new WS BASE flights that are impossible now with L/D=3.0 (e.g. no LZs within reachable now distance; all trees); insane flare (power management), going up much higher than currently possible. It's a crucial aspect for powered WS flight! This is because for level flight with engines, the thrust required is equal to weight divided by L/D: T = W/(L/D) Engines and fuel tanks reduce L/D, so suppose for modern mattress, L/D with engines is 2.0, then thrust required is half the weight! If we increase L/D by making the wing system more efficient, there's less thrust required for level flight. This is especially important for electric duct fan (EDF) engines which so far don't have as much power as jet engines. Maybe someday we'll be flying on electric power, but we need to push L/D as high as possible! The future of human flights starts now. From YOU. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  22. This is the foam that I purchased for the wing system: https://www.thefoamfactory.com/opencellfoam/LUX-HQ.html https://www.thefoamfactory.com/tech/Lux-HQTech.html 5" thick, 82x24", $71. Enough for the whole system, with some spare for practice. Good balance between firmness and foldability. The green or white/yellowish foam from Michaels, I think, if less resilient, lower quality, but should be good enough for early prototypes. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  23. Hard openings, imho, are caused by slider being "shaken down" under the cover of the cocoon if there's even a slight delay in wind blowing it off. This is especially true for wingsuiting with non-fresh ZP and even tracking (even tracking on break-off after a non-tracking jump). Exposing the slider so it's pushed by relative wind into the stops the first moment the canopy is out of the D-bag, solves the problem. It also greatly helps with reducing the occurrence of line twists. (see attached video illustrating cocoon hesitation) [inline Cocoon.jpg] On the other, less serious hand, hard openings are not always a bad thing: when I was doing my AFF, a hard opening fixed a problem in my spine with displaced vertebrae (from a big wave crush on my back when body surfing in the ocean), it settled them in proper place. I felt like I was born again. PS. Exposing slider is for experienced enough jumper, of course. Don't do it without packing/jumping at least 100-200 of normal pack jobs. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio CocoonHesitation.m4v
  24. Maybe the picture of Uncle Sam won't urge guys to enlist; how about the famous French Revolution tits? [inline RevolutionWithTits.jpg] Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
  25. Guys, if this is not clear yet to someone: this is not another "My little project" where one guy works on something and everybody just watches with popcorn. If you continue doing nothing and just waiting for me to build something, then most likely in another 20 years from now, in 2038, we'll be in the same state of CoW as now, and we'll have the same mattresses as now. This is YOUR project, OUR project. We ALL need to contribute and start doing something. NOW. If you're interested in building a foam wing system, then watch the DIY foam cutting video posted above, https://www.youtube.com/watch?v=ZlQZFib8PiM and start doing it! It's not rocket science. I've done it, and my hands grow from my ass. (This ought to be a sufficient proof that anyone can do it.) Initially, I used a light dimmer as a variable voltage source. Light dimmer can be purchased in any home improvement store and it's cheap: https://www.homedepot.com/b/Electrical-Wiring-Devices-Light-Controls-Dimmers/N-5yc1vZc34i Then you need a cutting bow (can easily be made from wood sticks) and wire. Nichrome wire is best, but guitar/piano wire works, too. But after burning many many wires, I decided to invest in a constant-current power source, about 100 bucks. Similar to this: [inline ConstantCurrentPowerSource.jpeg] With constant voltage, like with dimmer, if a "weak spot" appears in the wire, it gets hotter and hotter and burns; with constant current, the temperature is constant along the wire, there are no "hot spots", the wire lasts long time. For profiles on which the hot wire slides, I used this special temperature-resistant material I forgot the name of (maybe it's mentioned in the video, I didn't watch it yet). I don't have all these things with me right now and it will take months before I can show what I have. But just start doing your own research into this, it's simple, believe me, and when you finally cut an airfoil with it, it feels like you engineered something, vs. sewing something. That's the idea - let sewers sew, and us - engineers, scientists - engineer. For initial experiments with foam cutting and getting used to it, I recommend hard closed cell foam, like insulation/packaging foam (https://www.thefoamfactory.com/closedcellfoam/polystyrene.html) found in home improvement stores. But for real wings, we need open cell foam (by mistake, I called it closed cell in one of the first posts about it in this thread): https://www.thefoamfactory.com/opencellfoam/opencellfoam.html Can be purchased either online (they ship it in vacuum plastic bag so it takes much less volume) or in crafts stores like Michaels and even Walmart (sewing & crafts section). ZP fabric, or Parapack, or fabric/material of your choice, can be wrapped around finished wings and glued to the foam with upholstery adhesive (home improvement stores). Fabric will not only provide smooth surface, but provide strength and means of attaching wings to body platforms. Do it, do it, do it... The Great Wingsuit Revolution of 2018 has begun, don't remain in paralysis like a stooge worshipper! GWSR-2018 wants YOU, NOW!!! [inline GWSR2018WantsYOU.jpg] Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio