Tandem wings (Yes, again.... Sorry!)

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Thunderchook, Sep 29, 2016.

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  1. Oct 3, 2016 #21

    Tiger Tim

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    If expressed as a fraction (which I guess it isn't in reality) you'd get L/D but expressed as a ratio the forum software sees a colon and an upper case D and turns the latter two thirds of L : D into a smiling face... I assume.

    :D
     
  2. Oct 3, 2016 #22

    Swampyankee

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    Exactly true. Other forums using the same or similar software have the same problem. You can turn off smilies, but, as far as I know, only for the entire post.
     
  3. Oct 4, 2016 #23

    TFF

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    I think the Camel could take the F35.
     
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  4. Oct 4, 2016 #24

    pictsidhe

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    If the the pilots had to mow their own airstrip
     
  5. Oct 4, 2016 #25

    TFF

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    Not a fan of the F35. Big fan of the Camel. F-22 should have been the correct choice.
     
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  6. Oct 5, 2016 #26

    Swampyankee

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    Doesn't do well from carriers.
     
  7. Oct 5, 2016 #27

    Aesquire

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    Once upon a time there was a popular hang glider kit called the Easy Riser. A biplane, swept flying wing with "normal" stagger . A refinement of Taras Kiceniuk, Jr.'s Icarus 2.

    The rear ( bottom ) wing was at a lower angle of attack than the front ( top ) wing and thus was essentially an overlapping tandem wing.

    Quite stable, and one of the more successful early powered ultralights. Handy structure to mount an engine with a thrust line close to the vertical c.g.

    https://en.wikipedia.org/wiki/Taras_Kiceniuk,_Jr.

    http://www.pioneerflyer.com/Easyriser.html

    http://www.bydanjohnson.com/?b=1&m=3&i=25

    Camels didn't do too bad off a carrier.

    However when the casualties in WW1 in training flying the Camel were nearly as many as were shot down by enemy action, not to bad is a bit subjective.
     
  8. Oct 5, 2016 #28

    bmcj

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    Then build a plane for a carrier, you can't handicap a design with carrier or VTOL capabilities and still call it an air superiority fighter. The whole one-size-fits-all approach is misguided. [/RANT] [/THREAD DRIFT]
     
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  9. Oct 5, 2016 #29

    BJC

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    bmcj:

    You are being too kind to refer to it as misguided; it is more like insane, Robert McNamara style.

    wrt thred drift: https://m.youtube.com/watch?v=5_H-LY4Jb2M


    BJC
     
  10. Oct 5, 2016 #30

    rtfm

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    Hey bmcj - it was a joke...
     
  11. Oct 5, 2016 #31

    bmcj

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    Sorry. I thought it might be a joke, but the general topic of multirole fighters has a way of pushing my buttons. CX3aKKe.gif

    My comment was not aimed at you or your post. :grin:
     
  12. Oct 5, 2016 #32

    rbrochey

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    I was around carriers a lot when in the South China Sea in the early 70's, and I know for a fact that the Flying Flea (the thread here I think) could easily take off from the Hancock (CV 12)... JMHO
     
  13. Oct 6, 2016 #33

    Aesquire

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    Just be glad McNamara knew nothing of the Flying Flea or the entire fleet would have been tandem wing.

    There's a rumor that the reason the U.S. military changed all the airplane designations was because McNamara could never grasp the U.S. Navy system of type/model/manufacturer. I believe it.

    The Flying Flea variants tend to be quite good at short fields. A Q2 or Dragonfly is not, because of the reasons noted above.

    I wonder if the difference is simply wing loading?
     
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  14. Oct 6, 2016 #34

    Norman

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    I think so. On any multiple winged airplane the farthest aft wing is the horizontal stabilizer. On a tandem AKA "equal area canard" the H-stab is simply much larger than it needs to be. Since to be stable the aft surface must operate at a lower coefficient of lift than the forward surface there's a lot of wasted area in a tandem.
     
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  15. Oct 9, 2016 #35

    Jay Kempf

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    What if you had a long fuselage with an entire airplane at each end. That means a wing and tail at equilibrium (trim). If you had that as a tandem you could basically load the fuselage anyway you wanted and you could control the lift at each end and each end could be kept trim and not stalling. So what I am talking about is basically a freewing setup at each end. That could allow a HUGE range of CG locations for the payload and it would allow flaps on each wing. It would take a computer or another trim control to manage the AOA of the fuselage I would think.
     
  16. Oct 9, 2016 #36

    Swampyankee

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  17. Oct 9, 2016 #37

    jedi

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    OK, so load the aft aircraft heavier than the front one and then slow to minimum control speed. The aft aircraft will stall before the forward one and upset the apple cart. In physics, there is no free lunch. One technique that is typical is to make the system so complex that it is difficult to understand and figure out what is happening. Go back to the basics to determine if the proposal can work.

    The joined aircraft will will always be limited to the performance of the least performing aircraft speed wise as they must fly at the same speed. Performance wise power may be transferred thru the mechanical linkage. You could put the engine in the front or rear plane or one in each. You could also transfer fuel back and forth to control the CG and then operate at the most efficient trim. You can do that in the typical aircraft also if provisions are made to shift the load (or wing) for trim.

    The introduction of the free wing concept could prevent the stall but each wing must be trimmed for the existing weight distribution. The heavy wing would control the minimum speed.
     
    Last edited: Oct 9, 2016
  18. Oct 9, 2016 #38

    Sockmonkey

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    If only the aft wing on a tandem was a freewing, could you get away with loading them equally so as not to waste wing area?
     
  19. Oct 9, 2016 #39

    Norman

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    Since the aft wing is fulfilling the function of the H-stab letting it float freely would have the same effect as letting the tail of a conventional float, would it not?
     
  20. Oct 10, 2016 #40

    bmcj

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    Just string a bunch of airplanes together centipede-style.
     

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