Lifting body discussion

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Jeremy, Jan 31, 2007.

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  1. May 27, 2013 #101

    captarmour

    captarmour

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    very nice
     
  2. May 27, 2013 #102

    henryk

    henryk

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  3. May 31, 2013 #103

    captarmour

    captarmour

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    I want to applaud you for your courage and resourcefulness, in going ahead with this project and sharing so openly with us. This is really inspiring and an example to those who keep raking in investment money and show little for it. I hope all of us at homebuiltairplanes support you and encourage you. keep up the good work.
     
  4. Jul 3, 2013 #104

    gtex09

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    Thank you for your encouraging comments, Captarmour.
    Of course as soon as I can I will post more pictures of my scale 1:1 (GTx9-11-C).
    Rgds
    gtex09
     
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  5. Jul 7, 2013 #105

    gtex09

    gtex09

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    Hi,
    Weather is nice today...it's time to take some sun. Some news of the scale1:1 GTx9-11-C. Next step is related to the short wings assembly.
    Keep posted.
    Rgds
    P1040805.jpg P1040812.jpg P1040813.jpg
     
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  6. Jul 7, 2013 #106

    Jay Kempf

    Jay Kempf

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    That looks really well thought out. I would like to see or hear more details about the build and especially the retracts.
     
  7. Jul 7, 2013 #107

    gtex09

    gtex09

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    Hereby some more pictures during prototyping...
    Actually the tricycle gear is retractable, but I will not activate from the very beginning of trials, to not add to much critical things.
    :)
    P1040600 - reduced.jpg P1040132 - reduced.jpg P1040097-reduced.jpg P1040074 - reduced.jpg
     
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  8. Jul 8, 2013 #108

    zenj

    zenj

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    Thats a sweet looking landing gear, the blended wing fuselage looks the part also.
     
  9. Jul 8, 2013 #109

    cheapracer

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    Certanily helps to answer the question of how to use motorcycle front forks.

    Great build gtex! ;)
     
  10. Jul 8, 2013 #110

    topspeed100

    topspeed100

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  11. Jul 8, 2013 #111

    berridos

    berridos

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    Wooow havent noticed this thread. Impressive project. Are you aware that you are close to producing the first stealth homebuilt? Just avoid some curvatures
     
  12. Jul 8, 2013 #112

    Jay Kempf

    Jay Kempf

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    Really nice stuff. I am lost in CAD world on a clients project and it is nice to see actual pictures of actual parts. I like the way you have just used the struts and made simple and robust attachments. I also like the combination of simple 2 and 3d milling and sheet metal. Very manufacturable. Nice stuff.
     
  13. Jul 9, 2013 #113

    captarmour

    captarmour

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    wow! simply fantastic! keep up the good work!

    is the nose wheel free castoring or is it steerable?

    from the side view the axle looks ahead of the steering axis. like on a motorcycle if a straight line is drawn from the 'neck' or steering pivot or axis, to the ground, the axle should fall behind, or 'trail', that line for stability, (like a shopping cart steering).
     
    Last edited: Jul 9, 2013
  14. Jul 9, 2013 #114

    Workhorse

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    It looks impeccable. Those are motorcycle forks, are you sure they could stand the loads of a landing gear?. Weight distribution in bike I think is not 50/50.
     
  15. Jul 9, 2013 #115

    gtex09

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    Hi 'cheapracer'
    Well, actually, what I did is... look around me, with my friends (motos) what kind of stuff I could use to make it cheap !
    What is a main gear, hydraulic, for a plane ? If you check for the load, you can adapt the spring of a bike fork, like the Ducati Monstro (Showa), which is having a mechanically well guiding piston. The diameter and materials are very similar for the ones we know on aircraft....So just a couple of calculations, drawings, on how to adapt it, and that's it. I bought wheel from 4x4quads, and hydraulic disk brakes, then ones from small bikes, and then made the necessary adapting parts. I use ball bearings ('O' mounted) on a strong steel shaft, which is fixed on the extremity of the fork piston. To absorb the cinetic energy on landing I need some 150mm, maximum, which I will take splitted 30mm on the tire and 120mm on the cylinder. I will adapt the internal spring to the revelant force for this....It will work...:)

    TPAL drawing extract.jpg P1020201.jpg P1020206.jpg P1020213.jpg P1020518.jpg P1020519.jpg P1020524.jpg P1020527.jpg TPAL calcul resistance axe.jpg
     
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  16. Jul 9, 2013 #116

    gtex09

    gtex09

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    Hi Captarmour,
    Yes, steerable, it will be easier to steer the machine.
    For stability reasons I applied the angle like on bicycle forks (21°) and the positionning of the steering column axis behind the wheel axis, intersecting the wheel radius at around 0.25xR, as I already tested in my GTx9-09 model. ;)
    TAV Stability.jpg
     
  17. Jul 9, 2013 #117

    gtex09

    gtex09

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    We'll see... If weather, finances, time are OK, I hope being able to run part 3 by next spring or summer... I steel need to buy the gear between engine and propeller, need also to mount the engine (the BMW motorcycle is already bought, but I've to adapt the engine to my wing, with frame, and all equipments...) I also need to buy the propeller....So 'part 2' is not finished yet, but I forecast to be ready for some engine ground testing by next autumn.
    Keep posted !
    gtex
    ;)
     
  18. Jul 9, 2013 #118

    captarmour

    captarmour

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    I can see you have done your homework.
    In this diagram the 'trail' looks like zero, and does not show the decrease in steering angle of the leg as the front lowers under compression like in heavy braking for example.
    Most motorcycles have about 4 inches of trail with about a 25 to 30 degree 'neck'. 21 degrees is steeper than on a motorcycle, probably the much larger diameter wheel of a bicycle improves stability as compared to a motorcycle. With such a small nose wheel it may be better to err on the conservative side.
     
  19. Jul 28, 2013 #119

    litemite

    litemite

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    I am wondering/asking if anyone has any information on this picture? 12.5% wing minus winglets.jpg
     
  20. Jul 28, 2013 #120

    cheapracer

    cheapracer

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    Strange, I thought I answered this one - Cap is correct, there isn't enough trail by the looks of it but rake actually matters little unless of course the rake is the determining factor for the trail.

    http://www.homebuiltairplanes.com/f...s-new-technology/6806-slow-delta-wings-9.html
     

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