Skwrl 56 #1 May 20, 2009 http://www.theregister.co.uk/2009/05/19/darpa_goose_v_formation_ploy/ No word yet on whether the double chevron beats the single row wedge...Skwrl Productions - Wingsuit Photography Northeast Bird School - Chief Logistics Guy and Video Dork Quote Share this post Link to post Share on other sites
mccordia 73 #2 May 20, 2009 Quotehttp://www.theregister.co.uk/2009/05/19/darpa_goose_v_formation_ploy/ No word yet on whether the double chevron beats the single row wedge... Cool beans.. Do ignore the fact that full laminar airflown is something we lack, and actually flying in the burble/wake is not something that hapens in any form of wingsuit flight (let alone, flocking with sub-par performance) where its actually an advantage.. But cool beans...jets always rockJC FlyLikeBrick I'm an Athlete? Quote Share this post Link to post Share on other sites
Skwrl 56 #3 May 20, 2009 For my education, why/how do we "lack laminar airflow"? Isn't it just that we have a really crappy (i.e., far from the wing) laminar layer? I mean, all wings have a laminar layer, don't they - it's just a function of how good the wing is as to how much of the air "sticks" to the wing. (This assumption might be wrong.) As anyone who has seen me fly can tell you, I don't know crap about aerodynamics, so I'd be curious to learn more about this.Skwrl Productions - Wingsuit Photography Northeast Bird School - Chief Logistics Guy and Video Dork Quote Share this post Link to post Share on other sites
arai 0 #4 May 20, 2009 the P-51 was the first plane to be designed to use laminar airflow. However research data shows that they werent manufactured with enough surface quality to maintain laminar airflow on the wing. We fall quite short on the smooth wing required to achieve or maintain laminar flow Quote Share this post Link to post Share on other sites
mnskydiver688 0 #5 May 20, 2009 Ha, I guess I would compare a wingsuiter to the space shuttle. We both need parachutes to land too!Sky Canyon Wingsuiters Quote Share this post Link to post Share on other sites
notsane 0 #6 May 20, 2009 In this case, laminar flow refers to the uninterrupted flow of air over the wings. For a real aircraft wing in normal flight the flow over the top of the wing is fairly smooth, and there is no turbulence at any point. If you increase the angle of attack to the airflow, as you would when pull up on the stick, the airflow will detach from the wing, starting at the trailing edge. The higher the angle of attack, the more the flow over the top surface of the wing becomes turbulent. At some point, the flow over the top is fully turbulent, and the wing is no longer flying, but is merely displacing air, like a barn door, with its bottom surface, and is in a full stall. This is why there are many different wing shapes ... each tailored for different speeds and expected angles of attack. Us wingsuiters fly at a pretty high angle of attack, and the flow over most of our wings is pretty turbulent. Check out this video http://www.youtube.com/watch?v=LtQP1h_CPGE. Most of the time it's pretty hard to see the angle of attack difference, but at 2:49, it's pretty clear. You can be sure that the glider wing is flying and is cleanly into the airflow. The wingsuiter (Loic) isn't. There are also videos of wingsuiters with smoke that show the airflow direction pretty well. Compared to any aircraft wing, our wingsuits are pretty low on the performance scale. Scott Quote Share this post Link to post Share on other sites
Skwrl 56 #7 May 20, 2009 Funny you should mention that about smoke - I've been jumping smoke a bit lately and I've been amazed with how far forward (from my point of view) the smoke is pushed. So, for example, in full flight, legs extended, arms out, etc., I nevertheless will still see smoke by my hands. (In other words, it's going from the canister attached to my foot and moving forward to my hands as a result of the flow displacement).Skwrl Productions - Wingsuit Photography Northeast Bird School - Chief Logistics Guy and Video Dork Quote Share this post Link to post Share on other sites
mccordia 73 #8 May 20, 2009 Extended feet dont always mean a wingsuit is flying as well as it could. Putting too much pressure on the hands results in a more stall-y angle of flight also giving a much more turbulent airflow over the back, and thus a lot of smoke billowing/churning inside the burble. Smoke placement can also affect this of course, though on most video/shots of people doing 100% balls to the walls flying, the airflow over/allong the wing is clean, and results in the smoke parting (and actually disappearing in a turning fashion over/allongside of the s wingsuit burble..JC FlyLikeBrick I'm an Athlete? Quote Share this post Link to post Share on other sites
mnskydiver688 0 #9 May 20, 2009 Funny you should mention that about "balls to wall flying". Could you elaborate? I am looking to find a new flying style for my wingsuit flights. What are the physics involved with this "btwf" style? Sky Canyon Wingsuiters Quote Share this post Link to post Share on other sites
mccordia 73 #10 May 20, 2009 Its about having brass balls so big, they lower your center of gravity (making you fly better), and almost scrape the walls your flying past... I dont think there are many people who practice this 'balls to walls' type flying JC FlyLikeBrick I'm an Athlete? Quote Share this post Link to post Share on other sites
notsane 0 #11 May 20, 2009 The only reason that the smoke would be up near your hands is that it's within the turbulent area over your back. That would indicate that you're not really flying, but actually in a near to full stall with no airflow over any part of the top of your body. Jarno's pics show someone who is obviously flying for forward speed. Note that the arms aren't fully extended, but the legs are. The body is in a slightly cupped position. A faster forward speed will create more lift and ultimately allow very long flight times. It all comes down to flying, not falling as Yuri has often said. PF has an article on exactly this ... http://www.phoenix-fly.com/articles%20stvari/performance_flying_1.pdf Go up and try it out for a few jumps. You'll find that the load on your arms is much, much lower and the flight times/distances can be impressive. Scott Quote Share this post Link to post Share on other sites
Deniq 0 #12 May 20, 2009 QuoteFor my education, why/how do we "lack laminar airflow"? 1) on the image "IMG_1066" you can see typical aerodynamics problem - break-off of the flow on the suction side of an airfoil. 2) on the image "Flow visualisation" you can see investigations in an aerodynamics laboratory. The lift on the upper figure (laminar flow) is about factor 2 more in comparison to lower figure (turbulent flow). Quote Share this post Link to post Share on other sites
VectorBoy 0 #13 May 20, 2009 You guys keep this up and you know that Yuri is going to join the tread, do you want this? Quote Share this post Link to post Share on other sites
notsane 0 #14 May 21, 2009 I haven't seen any equations yet ... Quote Share this post Link to post Share on other sites
