Stability in a swept wing with no washout from the elevons alone.

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Michealvalentinsmith, Dec 3, 2009.

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  1. Jan 4, 2011 #281

    c p skeates

    c p skeates

    c p skeates

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    i find the trouble with ailerons and and an elevator on a flying wing is the subtile confusion in stalling when trying to opperate the in- sequence where as a tail takes the elevator away from the confusion ...:ponder:
     
  2. Jan 4, 2011 #282

    Topaz

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    Some amount of vertical tail area is usually beneficial unless one is trying to reduce parasite drag to an absolute minium. Piloted aircraft generally have a requirement to land in a cross-wind, and a strong yaw control and some level of yaw stability is beneficial to flying them.
     
  3. Jan 6, 2011 #283

    c p skeates

    c p skeates

    c p skeates

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    new ridgid wing hangliders are using just spoilers but because they can weight shift the pitch and to a small degree roll they can avoid the cross wind disadvantages but control aircraft cant ..we realy do know everything about aviation now compaired to the wright brothers 100 years ago so i believe the cannard-tail aircraft they started on has come a full circle with triple wing tandem wing aircraft now .. and modern materials to cut down drag so putting a very small cannard out front to oppose the pitch and a full moveing tail with no incidence is very efficient and stops tail slides as well as the benifits of a cannard wing because the cannard envolope is restricted due to tail slide and the tail aircraft are over simplified so materials are out of bounds but a triple tandem wing aith a full floating tail and no incidence with the smallest cannard up front to oppose the pitch can give a whole new lease of life to aviation with the sophistication we are about now with aerodynamics .. the european eurofighter cannard delta wing formation is the most sort after fighter aircraft in the world and the usa rapter is still to be past by congress for the last 20 years because the tail concept of an aircraft is no loger viable no matter how much they proprgander that it is still to come it will never be accepted due to materials limitations but the eurofighter useing a cannard and delta wing type of tripletandem type wing developement is selling like hot cakes ..
     
    Last edited: Jan 6, 2011
  4. Jan 6, 2011 #284

    c p skeates

    c p skeates

    c p skeates

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    a tandem triple wing developement type aircaft are now the future with absolute certainty .. triplewingtandemwingcpsuntitledreveresd.JPG sorry to go off track a bit but its relavent to the original thread so you can at least compair your self with it for a highly refined ruler type wing as the original thread here is maily concerned with ..thank you for your patient though ..
     
  5. Jan 6, 2011 #285

    Norman

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    absolute certainty?:suprised:
     
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  6. Jan 6, 2011 #286

    c p skeates

    c p skeates

    c p skeates

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    yes ... but back to elevons on a ruler type aircraft so you dont need an elevator and use the elevons for roll and pitch with out stall problems has been the way most craft of this nature have been made but sooner or later the manufacturere has opted for a tail because of sensitivity so the elevons have to 'friz' nature so the up aileron-elevon needs to produce a small amount of drag and the down untitledfriz12.JPG going aileron-elevon has to reduce drag or adverse roll will happen .Early 'PC' laminar flow aerofoils of the 1970's were used for full length flapperons on sailplanes to do every thing but lost favour .. if it wasnt for homebuilt aircraft scavengers like us where would the 'class' be ??
     
  7. Jan 6, 2011 #287

    c p skeates

    c p skeates

    c p skeates

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    too much stability is as bad as not enough ..:roll: every thing has a life until it dosent ..many home builders have come up with something which works only to find out the hard way later if they modify it to some degree they crash ..why .. if it works dont change it ..
    untitledanhedralfin12.JPG
     
    Last edited: Jan 6, 2011
  8. Jan 6, 2011 #288

    Topaz

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    Hi c p. Either I'm not following you very well, or there's a real lack of focus with this series of posts. Could you clarify the point you're wanting to make?
     
  9. Jan 7, 2011 #289

    c p skeates

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    perhaps im not following you too well could you please explain your detail ???
     
  10. Jan 7, 2011 #290

    Norman

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    I'd say that explaned it pretty clearly:whistle:
     
  11. Jan 7, 2011 #291

    c p skeates

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    thanks ..now your turn to do it ..hummm
     
  12. Jan 7, 2011 #292

    Norman

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    c p skeates

    Next time you post your insane rant I'll quote it in my reply
     
  13. Jan 9, 2011 #293

    c p skeates

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    :ban: untitledstablecock.JPG the mitchell wing ultralght as i under stand it has sweep back and elevons adjusted for washout instead of putting it into the wing it self so the elevator and ailerons act together as one so stall is delaid where if a elevator was made in the center it would over shadow the ailerons when stalling and upset the stall progression so the tips would stall before the center and cause a spiral turning dive spin ..hence the ideal is to stall the center of the wing first:devious:..so it is the belly piont where the air must separate first and work its way to the tips then escape from the wing in vortecies out side the wings envolope , untitledmitchellwingcos.JPG last making it all understandable to the pilots ability .
     
  14. Jan 10, 2011 #294

    c p skeates

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    early 1970's flying wings had elevons and sweepback wings as well as bombay doors for foot launch mandatory for legal status:mad2: untitledcpswingreve.JPG modern hangliders-ridgid wings are useing spoilers but are ineffective near stall so friz-ailerons-elevons still allow control and can enhance control near stall.
     
    Last edited: Jan 13, 2011
  15. Jan 15, 2011 #295

    danmoser

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    The Mitchell wing designs B-10, A-10, and U-2 all have external airfoil type elevons, which are noticeably more effective in a stalled condition than normally hinged elevons.
    Spoilerons are not effective as elevators for pitch control, so they cannot be considered as a substitute for elevons, per se.
    As you point out, spoilerons on modern rigid HGs are not as effective near stall.
    However, that is not really a problem on those HG designs that use the spoilerons, since they use the spoilers primarily for turning and glide path controls.... pitch is controlled via weight-shift, so no elevator is needed.
     
    Last edited: Jan 15, 2011
  16. Jan 24, 2011 #296

    c p skeates

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    i just dont trust the spoiler idea ..its effective except if a stall blankets over the whole wing i'd rather have a aileron or elevon as well for that final moment of control and be able to dive to get the flow over the wing back again than use the spoiler ..ridgid wing hangliders with just spoilers have shown to have little or no effect once the stall breaks the cord and so pitch is controled by weight shift but there is virtualy no control once the spoiler is in stall shadow though ..even if you have to use reverse aileron at least its controlable in stall ..
     
  17. Feb 4, 2011 #297

    henryk

    henryk

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    =we have composite KASPER-wing for vortex testing and orginal BEKAS glider for reconstruction,
    soon we shold be moore clever in this matter...

    PICT4976.jpg PICT4978.jpg Obraz=SONY,rysiek,bekas,pobiednik 131.jpg Obraz=SONY,rysiek,bekas,pobiednik 134.jpg
     
  18. Feb 12, 2011 #298

    henryk

    henryk

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    -first step... skrzydlo kompozytowe.jpg skrzydlo kompozytowe.jpg
     
  19. Feb 19, 2011 #299

    c p skeates

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    wow ..what a fabulous wing ..:shock:
     
  20. Feb 23, 2011 #300

    henryk

    henryk

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    ="fabulous"=? I dont understand...
     

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