LeeroyJenkins

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  • Main Canopy Size
    150
  • Reserve Canopy Size
    176
  • AAD
    Cypres 2

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  • License
    D
  • Licensing Organization
    USPA

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  • Tandem
    Instructor
  • USPA Coach
    Yes

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  1. LeeroyJenkins

    Wingsuit research

    CFD for now, as applied to wingsuits, is just a toy producing pretty colorful flow pictures. (See #2, 4, 7, 8.) They miss the most important first step: validation of simulations vs. real wingsuits. They get unrealistic max L/D (I've seen 4.0 and higher), which shows that their results have unknown (possibly no) relevance to real wingsuits. Their main purpose is to make pretty pictures. Give me a break, are you at least a mechanical engineer or aerospace engineer? So how long till you start selling your product/data? You marketing campaign seems to be off to an aggressive start?
  2. LeeroyJenkins

    hard openings dome slider?

    Here is a video for you. Take from it what you want. https://www.youtube.com/watch?v=zCM-eAekMCg Dammmnnnn those Safire openings were slow and crappy.
  3. LeeroyJenkins

    Jav D Bag

    Just removed the sewn on part. I used a jav D bag with a sky snatch for hundreds of jumps. It is no issue.
  4. LeeroyJenkins

    Wingsuit research

    To the best of my knowledge, true L/D and polar measuring devices I invented have never been used by anyone in Solar System other than the author. Smartphones and smartwatches are available. Apps (even free) are available. Telescopic poles are available. Simple materials are available. But no one has ever been interested in spending an evening or two to build a vane. 12 years since the idea publication, about 10 since Z-Device and Analog L/D Meter, 5 years since L/D Magic launch in Apple appstore, 3 years since free L/D Vario app, available on 4 platforms. Nothing. Nada. Imagine similar situation in any hi-tech industry (aerospace, cars, etc.) if someone invents the theory and devices to measure critically important performance parameters, and for 12 years they do this (and will continue for X more years): Hartman Rector is the only one who "gets it". Using polar curve deduced either from GPS data with wind correction, or from L/D Magic and L/D Vario, one can not only model their flights with arbitrary conditions and control inputs (to evaluate a prospective WS BASE jump, for example), but also model competitions for speed, distance, time to find the winning strategy (and it's all can be simply done in Excel, like Hartman does, no special software needed! although Wingsuit Studio can be used for piece-wise modeling since it only supports constant flight modes). Even when I mention 1.4=sqrt(2) (recently corrected to 1.3) as the best L/D for max horizontal speed and ask the competition champions what's their glide on speed runs and get ~1.6 (which is, more or less, 1.4 + wind push), I get a blank stare. They can't fathom that these things can be determined by scientific research, without leaving the couch even, and has been done 10 years ago! As I said before, unfortunately, despite all the guerrilla/gorilla/Godzilla marketing BS we get to eat these days, the wingsuit industry has been, essentially, in a coma since its birth 20 years ago. No wingsuit manufacturer knows the most important flight characteristic of their products - max L/D - or how to precisely measure it. And a lot of the research listed above is also just BS, the vehicle for students (or even professors!) to get their diploma/get funding and be out the door: Some research is genuine (Geo's, who was also a WS BASE jumper), but has errors or fallacies in it, stemming from aeronautical educational background, which puts emphasis on powered airplanes, not gliders. These fallacies get perpetuated and we get dangerous errors unintentionally disguised as scientific nuggets. As far as my performance numbers, I precisely measured my max L/D in Phantom-1 (2.15), Vampire-4 (2.75), and Aura-2 (2.9). I'm not fit, so for the same suits I would expect 5-10% higher numbers for athletic body build. PS. For PF tracksuit, I got 1.4, and for V-4 with cut armwings, in traditional tracking position/arms along the body, or in "Superman mode", with arms stretched forward, I get about 1.5-1.6 (but much faster than tracksuit). Unfortunately, I didn't have time or energy to pursue Superman flying more, because I always skydive my BASE canopy, and openings after Superman are really hard; and I don't have a physical strength to hold Superman position for long - the forces that try to bend you like a banana are incredibly strong! If anyone sees me at their dropzone, ask me, I can give you the leg wings of Phantom-1, V-2, or V-4 to try this "superterminal" flying. Where is your 3D flow simulations and modeling?
  5. LeeroyJenkins

    Rafale vs. Freak2 ?

    I know of several cases, besides mine. 1. Geo Robson from Switzerland, did some research on wingsuit dynamics, similar to Wingsuit Equations. Circa 2009-10. 2. Some student from Israel whose research paper I found by a web search. He was making small crude wood/plastic models of wingsuit and studying them in a small windtunnel. Circa late 2000's. 3. Someone wrote a paper on stability of Apache wingsuit using CFD simulations. Circa 2010-ish. 4. Icarus Project linked above. 2015-current. 5. Harman Rector did and does research on wingsuit dynamics using Wingsuit Equations expanded to 3D, using his flights and GPS data to first extract sustained polar curve, then using it to fit other flights and evaluate the feasibility of prospective flights. Recent 2 or so years. If there's anything else, publicly available, I'd love to know. Other than Hartman's 100% solid work and Geo's somewhat confusing work, the rest is just academia-type diploma-level kind of stuff (write a diploma paper and forget about it). To this day, I don't know of any attempts, other than mine, to use L/D Magic or L/D Vario apps (or their own apps) with a smartphone or smartwatch on a vane to accurately measure wingsuit flight characteristics. Or to use a Pitot tube the only proper way - on a vane, on a long stick. That manufacturers never showed any interest, never inquired about available L/D and polar curve measurement methods, shows that they don't do any serious scientific research to improve wingsuits. (It's like someone invented a Pitot tube, but no airplane manufacturers were interested - they continue developing their planes using a flapping scarf on a pilot sticking out the window: "this plane seems to be faster!". Or a car manufacturer never using a speedometer - "I simply watch the clouds of dust the tires kick!") Godzilla Marketing, not science, is their main weapon. But I would absolutely love to be proven wrong. Lol, ok. Not being publicly available =/= the research hasn't been done.
  6. LeeroyJenkins

    Rafale vs. Freak2 ?

    There has been scientific research done on modern wingsuits, saying there hasn't is absolute BS and an insult to the aerospace engineers that help design these suits.
  7. LeeroyJenkins

    EpicenePro

    I really like my Outlaw Lite. I am also pretty new to the base and land in a lot of small areas. Lots of sinking in approaches. I have head great things about the Hayduke, I think if I start doing more slider up stuff I will get one. If you are used to flying a base canopy like the outlaw the epicene has a pretty solid flare.
  8. LeeroyJenkins

    Easiest Stability Exits

    If you keep flipping over it's because you're not arching hard enough or you have too much surface area near your head. Probably a combination.
  9. LeeroyJenkins

    Easiest Stability Exits

    Talk to your instructor blah blah, When you exit, face the prop, Arch hard, legs straight, thumbs on your shoulders, you wont flip over.
  10. LeeroyJenkins

    Spectre or storm ?

    Squirrel Hayduke
  11. LeeroyJenkins

    Non-permanent marking of line attachment points

    Clothing dye and an eye dropper.
  12. LeeroyJenkins

    Helmet/goggle recommendations

    just wear sunglasses, plenty of people do it.
  13. LeeroyJenkins

    Roll packing technique problems/experience

    Lol, watching him do the S-fold was like watching one of those really bad infomercials.
  14. LeeroyJenkins

    Is my D bag too large?

    It's too big. Use smaller bands. It wont be a safety hazard. I don't even use my outer 2 locking stows.
  15. LeeroyJenkins

    Freak 2 proformance measure.

    Those of you with flysights, what kind of horizontal speeds are you regularly reaching on the Freak 2?