Yaw damping is usually more critical, though.
If comparing to other aircraft, for minimum sizing, I would want to know how well they perform, No use comparing to a low performance design.
Back in the wee days of the world....well maybe not that far back, the rule of thumb was if it looks right in comparison to the rest of the aircraft then you were good. If not, then you weren't. Still applies today. When looking at most general purpose aircraft , which is what most of us are flying, the overall look of the control and flying surfaces are in harmony with each other.Mind you, I say this while still in the preliminary stage, but the reason I don't *think* yaw damping will be the critical issue is the centralized mass. Just eyeballing, it looks like more than 50% of the aircraft's mass (including pilot) will be within about 24" of the cg. So it's more like a flying bowling ball than a barbell.
And the long wings should also help with damping as well. And given my lack of professional training, I am more focused on playing it safe than squeezing an extra ounce of performance out of it. I mean, just by using wet CF, I know I'm going to have a lot of variability and huge safety margins factored in from the beginning (and a good amount of necessary materials testing and verification).
But that's what preliminary sizing is for, right? Once I know roughly what it looks like, then I'll be able to figure out the details.
You know, I've heard it said that the biggest obstacle the Wright brothers faced when designing and building an airplane was not knowing what they are supposed to look like. At least I have BUGs, GOATs, Carbon Dragons, and ULF-1s to draw inspiration from, eh?
Where this deviates from normal aircraft is that I have no real mission requirements that it has to meet. Every iteration just goes through a loop of - can it be done Lighter? Can the fabrication be simpler for a homebuilder? Can you reduce the parts count? Can a flat panel or a simple curved part be used where a complex mold would normally be required?
So in a sense, it's sort of a modern composite ultralight primary glider that just pushes the performance envelope a little bit in every direction without sacrificing the core principles. The main structure, for example, is intended to be a 2-dimensional flat sheet of steel flashing, bent into the shape of a seat, and then used as a disposable mold to make a carbon fiber sandwich core, to which the spar is bolted, and the pilot is strapped. Optimal? No. Simple, light, and easy to copy in a garage as a one-off? For sure.
As I have gotten it from Lednicer and Roncz, yaw and pitch damping are a function of tail area and arm length squared, or put another way, tail volume times arm length. If you hold tail volume constant, then longer tail arms damp much better than shorter ones, even as tail area drops.
I've often wondered how something like Backstrom's plank copes with what must be relatively weak,yaw damping. Also, what's the vertical tail volume on a Horten sailplane? ;-)
Yes, all flying tails do fine with reduced tail volume coefficients. Paz showed that in his book.Does all flying elevator reduce the need for elevator area ? Why jets getaway with just Cht of 0.4 ?
Raymer's 0.04 coefficient is correct for Light Aircraft, I'm surprised that Sailplanes have half that coefficient, although I must say I have never looked at that in Sailplanes before and I can't understand why that might be.
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