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Showing content with the highest reputation on 02/24/2020 in all areas

  1. 1 point
    I still think Bloomberg should buy all of Trump's debt and then call it.
  2. 1 point
    Like this being actor George C. Scott, not General Patton?
  3. 1 point
  4. 1 point
    On their Facebook page, my message disappeared in just over two minutes. And also in the comments on the Altix photos.
  5. 1 point
    Listens to the tuba, of course. It has brought them . . . slightly less joy.
  6. 1 point
    Removed (How the hell can you delete a post here?)
  7. 1 point
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  9. 1 point
    Bottom line, though, we still don't know if the Earth is flat or not. We need another astronaut...
  10. 1 point
    I’m at the tail end of an epic boogie in the Maldives, and the sometimes dicey winds had me preparing to PLF (aka PLR, or parachute landing roll) on every jump. Because in the last 50 feet or so, you just didn’t know when you’d get the updraft, when you’d get the shear, and when you’d get the downdraft. A couple of people got hurt when they: a. Didn’t fly all the way through the landing (eg forgot to finish the flare because that downdraft came in the last 10 feet — sometimes you get unlucky) b. Just plain didn’t prepare to roll, and so hit stiff legged or with legs out like they were still planning to stand up. Passe though it may be considered in some circles, I’m still a fan of preparing to PLR (yeah, I like that name change). Remember, you have to land on every single jump, you should be prepared for a lot of possibilities in conditions Wendy P.
  11. 1 point
    After watching the video I would call this a non-issue. First of all you have to stand in front of the yoke and pull in an unnatural direction to make it happen. Secondly the rig does not actually come off the ground, the back of it just lifts a little, and you have to pull carefully and slow to make it happen. Your P?C generates about 70 lbs of pull force at terminal. That said, it should be easy to tell if it is having a real effect at deployment time. If it is catching, the 30 jumps or so you have done will be enough to show some friction wear either on the bridle or the tape on the flap. If there is damage happening at these points I would contact RI about it.
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  13. 1 point
    On second thought, how about Rudyard Kipling's "If?" That's one place to begin talking. If you can keep your head when all about you Are losing theirs and blaming it on you, If you can trust yourself when all men doubt you, But make allowance for their doubting too; If you can wait and not be tired by waiting, Or being lied about, don’t deal in lies, Or being hated, don’t give way to hating, And yet don’t look too good, nor talk too wise: If you can dream—and not make dreams your master; If you can think—and not make thoughts your aim; If you can meet with Triumph and Disaster And treat those two impostors just the same; If you can bear to hear the truth you’ve spoken Twisted by knaves to make a trap for fools, Or watch the things you gave your life to, broken, And stoop and build ’em up with worn-out tools: If you can make one heap of all your winnings And risk it on one turn of pitch-and-toss, And lose, and start again at your beginnings And never breathe a word about your loss; If you can force your heart and nerve and sinew To serve your turn long after they are gone, And so hold on when there is nothing in you Except the Will which says to them: ‘Hold on!’ If you can talk with crowds and keep your virtue, Or walk with Kings—nor lose the common touch, If neither foes nor loving friends can hurt you, If all men count with you, but none too much; If you can fill the unforgiving minute With sixty seconds’ worth of distance run, Yours is the Earth and everything that’s in it, And—which is more—you’ll be a Man, my son!
  14. 1 point
    Ever get a balloon or base jump when it feels all too good... you max out the suit, and you effortlessly fly at insane glide ratio, you experience the quietness and smoothness you've never experienced before and can't figure out what the hell is right? You may think that increased concentration and strength made you fly better. Well, now you can praise basic aerodynamics instead of praising yourself (or clown shoes)! The wingsuit equations are solved in the attached spreadsheet using the simple Euler integration method for some sustained horizontal/vertical speeds (which, as we saw, determine the adjusted lift/drag coefficients). For simplicity, we assume constant Cl and Cd (that is, the wingsuit geometry and angle of attack are constant) and zero-speed exit. You can change the values of Vxs and Vys to match your speeds. In this particular example, Vxs = 86mph, Vys = 43mph, L/D = 2.0. The graph PlaneoutTheoryVsExperiment.gif compares the calculations with one of the Phantom flights (the above parameters were chosen to best fit the experimental data). As you can see, from about 12 seconds to 24 seconds, the glide ratio is higher than 2.0 - we have a planeout with maximum glide ratio as much as 35% higher than the sustained glide ratio. The graph PlaneoutVsWingloadingAndLD.gif shows the dependence of the planeout duration (time period when glide is better than L/D) vs. wingloading. The heavier flyers experience longer planeouts which start later. The graph of glide ratio increase vs. L/D shows that the planeout effect dramatically increases with the increasing L/D: the better you fly, the more you can be fooled into thinking that your insane glide ratio is your L/D. PlaneoutVsLD.gif shows the trajectories and glide ratio vs. time for different L/D. Unlike intentinal dives and spirals and subsequent high-speed planeouts with quite high g-forces in skydiving, the smooth transition into full flight on a base or balloon jump hides the planeout in virtually unnoticeable ~0.1g decelerations that bleed your speed ever slowly, but do make your glide substantially better than your actual L/D. In conclusion, - when analyzing GPS data from a base or balloon jump, discard the first ~30s of the flight, even if it has a linear portion that looks like a sustained flight... it's not! (or better yet, correct the glide ratio for acceleration using the formula above) - planeout effects can also manifest themselves when you change your body position and feel the decreased fallrate and improved glide - only to lose it in a few seconds. It could simply be a planeout! (again, accurate acceleration data can help you see if the improved glide was real or "fake") - after the planeout, you will experience temporary "drop", a decrease of glide ratio even below your L/D. Plan your "do it or die" jump accordingly. - heavier jumpers will experience the planeout effect longer. Vampire will exhibit stronger planeout glide imrovement than Prodigy. The higher the performance, the better the planeout - and the worse the "drop" after it. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio
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