aiplane design
 

hi all,is it possible to design a plane that as no coupling at all ?or am I dreaming:D
I design an build a plane back in 99 that as no coupling on rudder input,I can do a flat turn with no ail input, kE is the same but i do need to had a tad of down elev in KE.correct me if im wrong but my plane is nose heavy so i need to dial in some up trim to aquire staight flight.so if i would had some tail weight so that the plane fly's straight with a neutral elevator I would probably have no elevator coupling in KE.Am I right?
im gonna post a pic that i took last weekend so u can have a look at my design.its not really hi res pic tho.

jeang

RE: aiplane design
 

yeah, what you have said sounds right. nice design, does it 3d?

RE: aiplane design
 

yes, but im still learning,cant even hover yet but getting there.Its powered by a YS 45 on a pipe an weight 5lbs .4oz dry.

jeang

RE: aiplane design
 

If you're willing to cut away or fudge on some control and fixed surface area as required then yeah, I'd say so. But to do it on the drawing board and get it right the first time? I'd have to say that it would be good luck more than good planning. So many things enter into the equation that I think you would be just guessing. Of course there's enough practical experience that a decently educated guess would be pretty close but in the end I think it would be prudent to arrange for some extra area above and below the model's center line that you can cut away or add to in order to play with the balance.

RE: aiplane design
 

Look at a typical "Hots". These have the engine, wing and tail on the same line, and are VERY easy to fly airplanes! Coupling is minimal..