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Aerospace Pretty Sweet Video

  1. Jan 25, 2010 #1

    FredGarvin

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    Here is a video of a BO-105 getting put through its paces. I remember seeing the German Army every once in a while flying these. They are pretty cool little helicopters. This is pretty close to the UH-72 (EC-145) that we are in the process of replacing the OH-58 with. Rigid rotors are pretty sweet.

    http://www.glumbert.com/media/flash/player.swf?file=aerobatics&autosta

    There are a couple of notable moments I think. The first is when they put this inverted and do a downward spiral on the rotor. The other is what looks to be a sort of rolling knife edge. It definitely is a plus to have the camera angles from inside the cockpit at the same time. Enjoy!
     
  2. jcsd
  3. Jan 25, 2010 #2

    RonL

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    Thanks Fred,
    I needed to see that to help my mind confirm the thoughts, that a full sized machine is not as limited as most people think.
    There have been too many videos that show models doing such crazy flight patterns that seem so impossible, yet they are real events, such flying has no appeal to me and only shows an incredible amount of skill and coordination in using remote controls.

    Brings to mind a question, how many things can a humming bird do that an eagle can't ??

    Ron
     
  4. Jan 25, 2010 #3

    turbo

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    Wow! I would not want to be on a ride-along for that! Urp!!
     
  5. Jan 25, 2010 #4

    Borg

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    Sounds interesting. I'll have to check it from home (streaming videos are blocked at my work).

    FredGarvin, I saw this the other day and it reminded me of your avatar. I hope that you like it. :smile:
    http://pix.motivatedphotos.com/2010/1/14/633990422268865910-murphyslaw222themarkofatrulsuperiorpilotistheuseofhissuperiorjudgementtoavoidsituationsrequiringuseofhissuperiorskills.jpg" [Broken].
     
    Last edited by a moderator: May 4, 2017
  6. Jan 25, 2010 #5

    FredGarvin

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    I have seen that in a bit different wording. I think I like that one better. Thanks!
     
  7. Jan 25, 2010 #6

    FredGarvin

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    While I don't like the RC guys I will admit that some of the stuff they do is plausible. Not all of it. Inverted hovers for example. I don't doubt their abilities to do it, but I am a scale purist so I don't like seeing the silly stuff. The number of aircraft out there with rigid rotor heads and the performance to do those moves are very few.
     
  8. Jan 26, 2010 #7
    Isn't there still a danger of losing control during these kinds of low-g maneuvers? The pilot must be compensating for the roll caused by the tail rotor as the rotor disc becomes unloaded.
     
  9. Jan 26, 2010 #8

    FredGarvin

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    I'm not sure as to the degree that the unloading happens. I am sure you have to ease up or even opposite pedal when these moves happen but to what degree I have no idea. I would also assume that momentum helps carry you through the maneuver to a point where the loading resumes.

    It is for that very reason why I was impressed with the "rolling knife edge" he was doing. Granted, he had to be falling to do it, but there was obviously plenty of pedal to keep that aircraft yawing while in a 90° bank.
     
  10. Jan 26, 2010 #9

    Astronuc

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    Pretty amazing stuff! :cool: :tongue2: And seemingly unnatural. :bugeye:
     
  11. Jan 26, 2010 #10
    it's amazing,the pilot might be the most experienced one, he's a fearless man,thanks fred .
     
  12. Jan 26, 2010 #11

    Borek

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    So, everything I was told in the "Blue Thunder" was a lie.

    Another reason to not trust people who one day pretend to be a afraid of water and other day pretend to know how to fly a helicopter.
     
  13. Jan 26, 2010 #12

    FredGarvin

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    Roy Schneider was the man. I have "whisper mode" for my truck. It works great.
     
  14. Jan 29, 2010 #13

    Borg

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    Finally watched it from home. Nice! :cool:
     
  15. Feb 5, 2010 #14
    Last edited by a moderator: Sep 25, 2014
  16. Feb 10, 2010 #15
    Thanks Fred, that was awesome.

    I didn't know inverted flight was possible? I know the basics of helicopter theory, I am currently doing a project on helicopter rotors and did my dissertation on human powered helicopters, but havn't really looked into flight limitations. How does inverted flying work from an engineering point of view? Does it only work with a certain type of aerofoil, or can the angle of attack of the rotors be set to a position where they will produce a positive lift from an inverted position?

    Sorry if this question is a bit basic, Im still becoming familiar with the subject.

    Marty
     
  17. Feb 10, 2010 #16
    I think the biggest limitation is the rotor system. Helicopters with teetering rotors can experience catastrophic failure under low-g conditions (mast or tail bumping).
     
  18. Feb 10, 2010 #17

    FredGarvin

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    Like I mentioned in the original post, it is all possible with a rigid rotor. The only drawback is that all of those bending moments get directly tranferred to the rotor hub.
     
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