Sep 2, 2018, 3:21 PM
Post #1 of 3
Here are some resources about wingsuit research in the last 12 years or so for those interested. If you know of anything not listed, please share. Let's keep this up-to-date as a central "What's new in wingsuit research?" reference.
(additional experiments with top above waistline removed for Phantom-1 and Vampire-2, circa 2012-ish and with arm wings cutoff completely on Vampire-4 and flying like a Superman, with arm(s) stretched forward, circa 2015-ish)
YB8 - Z-Device, with accelerometer and Pitot Tube on a vane:
I just started to read #8, the big dissertation (1000 pages!), The Effect of Surface Materials and Morphology on Wingsuit Aerodynamics. And immediately was SHOCKED to find that it falls into the same fallacy as Geo did - applying the math for powered level flight to wingsuit flight!
I pointed about this confusion many times in wingsuit forum. Hopeless. In 2009, Geo wrote this post:
- apparently, this was part of his preparation for that fatal jump. And it's quite possible, that this Great Confusion cost him life, if there was an error in his calculations (BFL #146).
Cf. pages 47-49 in the Sestak's dissertation. As Geo, he separates total drag into two parts: induced drag and parasite drag. As I explained in "The Great Confusion" post and in reply to Geo, this is an artificial math trick designed to make life a bit easier when doing calculations related to powered level flight, but they are useless and even harmful, when applied to non-powered gliding flight!
Wingsuit's drag does not go to infinity as the speed approaches zero, otherwise, we'll be like a fly that flew into honey, after a BASE exit, since the enormous drag will stop us right away! Drag is always (with high Reynolds number) proportional to the square of airspeed!
Unfortunately, the way they teach aerodynamics to aeronautical students, pounds this fallacy into their brain. From my observations over the years, aeronautical students and engineers do not have a solid grasp of fundamental physics concepts to recognize this fallacy. They fall into this pothole every. single. time.
Finally, both Sestak's and Robson's work fail to mention the prior art - Wingsuit Equations (ca. 2006) and L/D Meter principle (i.e., the possibility of precise measurements of wingsuit flight characteristics) - in their work. (Robson learned about WSE and Wingsuit Studio in 2009.) Wingsuit Equations are like Newton's F=ma in wingsuit dynamics. For an aeronautics researcher who is also a wingsuit pilot, to not know about them in 2017 is laughable, they are easily googled by "wingsuit dynamics", etc. It's like writing a doctoral dissertation on mechanics and not knowing F=ma. Or like a Ph.D. candidate in electrical engineering doesn't know Ohm's Law. You can run, but you can't hide from the Wingsuit Equations!
(This post was edited by yuri_base on Sep 3, 2018, 11:13 AM)
Everyone is most welcome to compile their work in a post here. Your thoughtful posts here on bj.com, dz.com, or elsewhere, articles you wrote, calculations you've done - share the love, don't be shy! It will be a very interesting read. Everyone remembers what they've done over the years; but not what others had done. It's like a ton of needles thrown from a plane onto a field of haystacks. Who can find them all?! Collect all your needles from your haystack and give it to us!
If you have any critical thought on any material in this thread, go ahead, shred it!
True science does not know "politics", little talk, tact, pretty lies... True science is the pure truth, it's fucking straightforward!