Lazy bee derived LAR design

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Hephaestus, Jan 1, 2020.

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  1. Jan 15, 2020 #181

    Hephaestus

    Hephaestus

    Hephaestus

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    Yeah, I'm not planning major changes - if you want to discuss other LAR concepts - feel free to start a different thread.
     
  2. Jan 16, 2020 #182

    lr27

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    I think you should get Trexler to sponsor you by making a special, very large,set of wheels. With their name on the wheels, of course. Or maybe Dubro. :)
     
  3. Jan 16, 2020 #183

    Sockmonkey

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    And here I went and did this.
    [​IMG]
     
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  4. Jan 16, 2020 #184

    cluttonfred

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    Cute but not at all "Lazy Bee" IMHO....
     
  5. Jan 16, 2020 #185

    erkki67

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    the fuselage needs some tapper upwards and the rudder needs a serious redesign, and no stinking wheelpants.
     
  6. Jan 16, 2020 #186

    Sockmonkey

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    It does taper upwards, and I like wheelpants.
     
  7. Jan 16, 2020 #187

    pictsidhe

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    It needs more taper. It needs a greater angle of attack while on the ground.
     
  8. Jan 16, 2020 #188

    rotax618

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    If you look at Zimmermans work on LAR L/D you will see that AR of 3 is not particularly efficient, L/D only starts to increase from about 3 and is best at 1.27. There are other benefits of low AR in sport plane design, compactness, low stress and therefore weight, Stall and spin resistance etc.
    At very low AR the 3D characteristics of the whole wing planform is more important than the 2D characteristics of the airfoil. To best mitigate the adverse effects of induced drag it is also important to keep the wing loading low.
     
  9. Jan 16, 2020 #189

    cluttonfred

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    1.27 being the aspect ratio of...a circular wing. Let's see, a VP-2 has a wing area of 130 sq ft.... ;-)

     
  10. Jan 17, 2020 #190

    plncraze

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    Will Sockmonkey's design pitch down with power?
     
  11. Jan 17, 2020 #191

    BBerson

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    That effect is only at around 30° angle of attack.

    In the range of 5° for climb the Ar-3 is significantly better L/D than the AR-1
    All of them have very low L/D at 30° for a steep glide.
    Yes, if you have 50hp for a single seat the extra drag doesn't matter in climb.

    Figure 5 here:http://naca.central.cranfield.ac.uk/reports/1933/naca-report-431.pdf
     
  12. Jan 17, 2020 #192

    Sockmonkey

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    I model stuff in flight orientation. Here's a side view. As you can see, the taper is enough to allow a decent landing angle.
    [​IMG]
     
  13. Jan 17, 2020 #193

    lr27

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    Depending on the aspect ratio, it may need to be a little more nose up when landing than the fuselage allows. Plus, of course, it doesn't have that Lazy Bee charm, although it's,not actually bad looking.
    -----------
    Had nothing I actually wanted to do more, so I looked into wheels some more. I'm not sure fat tires on bicycle wheels would save much, if any weight or money compared to Asuza plastic wheels. The latter would be somewhat smaller, but I doubt they'd look out of place. OTOH, homemade carbon wheels might be lighter than either, and scrounged wheels from the bike store dumpster might be cheaper. The classiest would be to somehow fake giant Trexler wheels. I wonder if there's some way to suitably reinforce inner tubes without special equipment?

    In another department, I wonder when ship breakers will get to those LNG tankers. At that point, maybe balsa would get cheap enough that this plane could have a truly scale structure.
    (Rumor has it that the tanks in the LNG ships are insulated with balsa.)
     
  14. Jan 17, 2020 #194

    Sockmonkey

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    The rear end can be sloped up sharper without messing up the design so no problem with the change.

    Maybe go with tubeless tires? There are instructionals on youtube showing how to cheaply seal regular tires to rims so you can inflate them.

    Since you want your plane level during the takeoff run, and only pitching up at the end, taildraggers have a disadvantage there.
    So, I'm thinking that a tail gear that's tall, but can be folded back like it was retracting by pulling a lever might give you the best of both.
    It wouldn't actually retract, as you want it exposed if you have to abort. It would just fold back a bit to let the plane tilt into a nose-up position.
    Wouldn't be complicated to do, and would shorten the takeoff run.
     
  15. Jan 17, 2020 #195

    lr27

    lr27

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    Tubeless tires probably wouldn't look any more like Trexlers than they would with tubes. OTOH, if you could make an inner tube sturdier, it WOULD look like a Trexler.
     
  16. Jan 17, 2020 #196

    Sockmonkey

    Sockmonkey

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    You could mount a tubeless tire on a wider rim, then it would look balloon-tire-ish enough to fit the theme.
     
  17. Jan 17, 2020 #197

    erkki67

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    Taper upwards not to a pinpoint , but to approx 1,5’ in height, and having an flying rudder
     
  18. Jan 17, 2020 #198

    erkki67

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    lazy bee.png

    I was thinking more of a Lazy Bee tail .
     
  19. Jan 17, 2020 #199

    Hephaestus

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    again...

    Take your discussion about a tailless plank design somewhere else please.
     
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  20. Jan 17, 2020 #200

    erkki67

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    Yes Sir, done.
     

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