alberto1980

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Gear

  • Main Canopy Size
    135
  • Reserve Canopy Size
    126
  • AAD
    Cypres 2

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  • Years in Sport
    13
  1. I just switched from a Vengeance 150 to a Katana 135, and I regret it. Vengeance opens way better, slightly less ground hungry which is a good thing. Get it till you find one.
  2. In Aviation they call it the drift towards failure. It is well known in aircraft maintenance. Even the FAA knows about it
  3. When is next attempt? if you land it you are my superhero. Respect :)
  4. Well the slider here plays a big role since it makes the canopy 'arch' a lot when it is up there close to the fabric (extreme camber during deployment, see attached pic) so this is not true and canopy collapse beyond stall angle of attack proves it. Note though, canopy stall is not related to its failure to get air through the nose. I am pretty sure that NOVA issue was in fact related to airfoil / planform shape or a combination of the two more than air intake design.
  5. I am always in awe when realizing that aerodynamics is such a widespread and enjoyable hobby
  6. Correct me if I am wrong but loaded above 1.4 or not, this is definitely a drawback of a partially open ram air canopy nose. if it collapses there's less intake area to restore its shape. On the other side there's also less intake area to let the air out. But what I really think is that the intake is designed to be at the stagnation point on the wing, and if you load it light this stagnation point is above it (flying at lower angle of attack), therefore the intake is less effective.
  7. Best of luck man, this is great, I can't wait to know how this goes.
  8. do you think those two little white loops hold your weight? 3 ring system = triple mechanical advantage
  9. Hi I think it is pretty clear why beyond a certain optimum wing loading there is a performance penalty. That's because every wing has an optimum glide ratio at a certain lift coefficient (see pdf attached). Let's say you are doing a distance competition. your speed is given by the trim angle of the canopy and your weight mainly. so you can imagine now to change the size of your canopy to get at the maximum glide ratio: you are now at the best loading for your wing in terms of aerodynamic efficiency. Load it more, performance degrades. That is why an airline plane climbs higher and higher during a flight, to compensate the weight decrease with density decrease (and therefore fly at the same CL with different weights): they want to fly at the best efficiency, set speed and save gas. if you take the same canopy now, let's say a vengeance and you plot the figure I sent for different sizes, the curves will shift to the right as you decrease the size (square feet of the canopy), therefore the best glide ratio will be at a slightly higher CL. This is because of Reynolds number effects: but remember the graph is for the drag coefficient! There will be also an optimum size for the minimum drag when the CD is multiplied by the area to obtain the drag. Decrease the size even more (at constant wing loading) and you decrease performance. So for a pure distance performance, there is an optimum wing loading and an optimum size.
  10. LEGAL leagle sounds like a french eagle
  11. yes but you still have the mesh holding the pilot chute fabric right? well then wouldn't it inflate? A rigger please step in
  12. *** If the kill line AND apex support tapes ALL broke, then the P/C would indeed streamer. *** Could you please explain this?
  13. I do not suggest you trying that, but giving in spin ailerons make the spin steeper and steeper until the aircraft gets out of the spin. personally tried on a pc21. I am not sure it works on a twin like an Otter though..
  14. I think the only way to get out of a back spin without thinking too much about it, is to give 'in spin' ailerons and getting the spin steeper and steeper until the aircraft gets out naturally. From the video though the spin seems pretty steep, definetly not a flat one. that is also why they experienced hi g forces. there's another video like this with a Britten Norman Islander stalling and then going into a spin while on jump run. It's on youtube somewhere, but they recover the aircraft after a few turns . If it was a certified aircraft, it would have gone through a stall characteristics certification, which includes spin demonstration unless an artificial stall is set with a stick pusher or something, but I do not think this is the case. That vertical tail is tiny, I am not surprised this happened. everybody seemed to walk away and for the aircraft who cares