While we're getting bored with Raptor, here's a new one to critique...

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by foolonthehill, Jun 19, 2019.

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  1. Jun 20, 2019 #21

    rv7charlie

    rv7charlie

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    Meh... Given how 'alternative' the entire build looks, it's conceivable that he got it inspected, and then decided he could do something better/different.
     
  2. Jun 20, 2019 #22

    Hephaestus

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    Or just built it for his own personal enjoyment and doesn't feel the need to show off.

    Or it will be for a kit later but they want to get it right first without investors breathing down their necks about when it'll be ready. Or making false claims/statements before it's proven ;)
     
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  3. Jun 21, 2019 #23

    bmcj

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    It could definitely pull off wearing a SkunkWorks sticker.
     
  4. Jun 21, 2019 #24

    pictsidhe

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    I don't like the the thrustline, looks very high.
     
  5. Jun 21, 2019 #25

    flyboy2160

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    Agreed. The Facetmobile leading edges are tube-diameter 'sharp,' but they have a much larger included angle, which may be more like a conventional rounded nose.

    But I don't really know anything about these very low aspect ratio wings, which is why I was hoping Barnaby would chime in.
     
  6. Jun 21, 2019 #26

    Riggerrob

    Riggerrob

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    Aurora platform looks similar to the double-delta-diamond of Dyke Delta. If he copied the Dyke - with the later drooped leading edge - he has a proven wing configuration.
    The split rudders limit spa wise propagation of turbulence generated by the propeller .... especially when power is pulled to idle.

    Like the rest of you, I wonder about the high thrust line.
    How much does pitch change with throttle changes?
    Would angling the thrust line improve pitch stability?

    As for the lengthy delay since 2001 completion .... and hiring Elliot Segiun as a test pilot ..... I suspect that they are still trying to refine handling.........

    Sure would be nice to hear Elliot’s side of the story .....
     
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  7. Jun 21, 2019 #27

    Little Scrapper

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    This was taken today.
    Screenshot_20190621-140853~2.png
     
  8. Jun 21, 2019 #28

    BJC

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    I hope that they get it to Oshkosh.


    BJC
     
  9. Jun 21, 2019 #29

    narfi

    narfi

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    There is something very strange about the 1/2 and 1/2 image of the man on the left divided by the prop blade, it looks like two different people spliced together........

    Edit: zoomed in I see it now the reflection on the blade gives the false impression of an upright torso in grey tshirt while hiding the bent over plaid torso.
     
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  10. Jun 24, 2019 #30

    bwainfan

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    [QUOTE="flyboy2160, post: 477900, member: 31286"]Agreed. The Facetmobile leading edges are tube-diameter 'sharp,' but they have a much larger included angle, which may be more like a conventional rounded nose.

    But I don't really know anything about these very low aspect ratio wings, which is why I was hoping Barnaby would chime in.[/QUOTE]



    Facetmobile had sharp leading edges, not "tube radius" edges. There were bent aluminum leading edge pieces over the leading-edge tubes.

    I do find it remarkable (and somewhat dismaying) how many people on this forum make apparently authoritative statements about my airplane that are wrong. I don't have any idea where some of these ideas are coming from other than people making incorrect assumptions and restating them as fact, but I would be obliged if people would check their information before making such statements.

    As far as chiming in on the thread about the airplane you are discussing (or any other project in progress) I have a strong personal policy against critiquing other peoples work on public forums.
     
  11. Jun 24, 2019 #31

    pictsidhe

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    Could we bait you into a tangential discussion on vortex lift?
     
  12. Jun 24, 2019 #32

    flyboy2160

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    Facetmobile had sharp leading edges, not "tube radius" edges. There were bent aluminum leading edge pieces over the leading-edge tubes.

    I do find it remarkable (and somewhat dismaying) how many people on this forum make apparently authoritative statements about my airplane that are wrong. ....[/QUOTE]

    I apologize for an honest error, but I never posited my opinion as 'authoritative,' as some of my other comments indicate the opposite. One of the pictures of the rebuild didn't yet have the folded leading edges. The observation about the included angle looking much larger/a thicker airfoil section is still valid.

    Several of us here wish you would comment, even if it's just about the aerodynamics of these things in general.
     
  13. Jun 25, 2019 #33

    Tench745

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    Looks a lot like what the Defender would be if it flew.
     
  14. Jun 25, 2019 #34

    pictsidhe

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    Uh-oh.
     
  15. Jun 26, 2019 #35

    deskpilot

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    My version of a single seat Dyke Delta. Designed but never built,

    EagleRay.jpg Frame and inst panel.jpg Mk3 build (Copy).jpg
     
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  16. Jun 26, 2019 #36

    narfi

    narfi

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    Do you have to remove the engine to change cylinders?
     
  17. Jun 26, 2019 #37

    bmcj

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    Why not allow the engine to hinge upward on the two upper mounts for easier maintenance. One or two other designs had sideways swinging engines.

    Of course, it might me easier to make the forward structure removable.
     
  18. Jun 27, 2019 #38

    billyvray

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    I saw it come up on a facebook post the other day. It hasn't flown but it is about to start flight testing.
     
  19. Jun 28, 2019 #39

    deskpilot

    deskpilot

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    Hey Narfi, if you're referring to my model, well ya know, I hadn't even thought of that. Just to be curious, I went back into the models, rescaled my VW motor and tried it for fitment. Hmmm, maybe removable side panels and a little change to the fuselage structure would do the trick.
    scaled engine.jpg
     
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  20. Jun 28, 2019 #40

    narfi

    narfi

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    Could you stop the fuselage tube structure at the firewall?

    The engine mounts from the firewall like any small engine. The cowling be a very wide two peice cowling that also doubles as the leading edge wing fairings?

    This would give you full access for maintenance on the engine.
     

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