The short version is below the bold title 
21 feet, double tapered wing with flaperons. Vdive something like 300 kts. Hingeline of the flaperons is straight and actuation is 40-50 degrees downward and 30-40 degrees upwards, chord depth is 25%.
Full differential flaperon control, the up-motion should be about twice as big as the down motion. Key to my ideas is a very simple wing structure without any actuators, push/pull tubes or other stuff in the wings. Nothing, except for fuel and tip lights. Thus, I want the flaperons to be driven from the fuselage, where it can easily be disconnected from.
Wing structure is conventional composites, 2 spars, sandwich cored skin panels, drag spar should take all forces of flaperon.
I also want negative (upwards) flap deflection, and quite a lot of it, being 15-20 degrees, maybe a bit more. This seems as the ideal speed brake for high velocity descents. It lowers maximum lift and thus avoids structural overloads (Clmax about 0.5, dcl/dalpha is also flatter), causes a big rise in drag and doesn't require any extra "stuff", or power. I realize it reduces roll rate by an enormous amount, but above 200 kts, I guess I'll still have plenty of it
Both ailerons and flaperons are strictly mechanical. Actuating forces in my speed range will be low enough to make that possible. A very nice feature of this is that one can use negative flaps during T/O and landing. By that, you have excellent aileron control (cross-wind), without any tendency to lift the wing. Also, the wing won't stall as soon (I'm designing a taildragger, which often stall their tips during low speeds on the ground). During an X-wind landing you're also able to put the landing gear on the ground, go full negative and have full weight on your wheels.
I'm aware of the limitations of flaperons. I've flown with them quite a lot and am convinced I can make it work just as well in a powered aircraft. Landing deflection shouldn't exceed roughly 30 degrees (down). The wider deflection limits are for the combination of full flap (negative or positive) and aileron deflection. Wing deflection is taken into account.
A logical approach seems to make the flaperons with a torque tube (composite) that can drive the whole flaperon and have a counterweight (flutter) on the inside of the fuselage. A torque tube is stiff enough to easily bear all mechanical forces, but flutter is a serious consideration. Flutter, where the tip of the flaperon turns around the tube and where the flow and eigenfrequentie of the torsional vibration of the tube match might be a problem (that can be solved by making the tube stiffer)
I opened this thread to think about the actual attachment of the flaperon to the wing. Billski had an interesting thread about this, which got me thinking about the hinging of the flaperon.
In Short
Fuselage-driven flaperon, with a torsion tube in the LE of it, how would you hinge it?
Since we're talking straight flap(erons), without a gap (in fact, sealed over by mylar), there're basically 4 options.
The first one is a bearing around the torque tube. I've no idea, but there should be available something to hinge it this way, like on the crankshaft of a piston engine?
The second one is to hinge it only on the outer and inner side of the wing. That's about 9' long and much simpler. But is this realistic?
The third one is to cut the torsion tube on 1 or 2 places, hinge it there (in the middle of the torsion tube, much like most other flaps/ailerons are hinged) and built a structure around it, to make it stiff enough torsionally.
The forth one is using a piano hinge on the lower side of the wing skin. I don't like the idea of screwing hinges on it, but full span carbon hinges sound like an interesting idea:
Manufacturer
21 feet, double tapered wing with flaperons. Vdive something like 300 kts. Hingeline of the flaperons is straight and actuation is 40-50 degrees downward and 30-40 degrees upwards, chord depth is 25%.
Full differential flaperon control, the up-motion should be about twice as big as the down motion. Key to my ideas is a very simple wing structure without any actuators, push/pull tubes or other stuff in the wings. Nothing, except for fuel and tip lights. Thus, I want the flaperons to be driven from the fuselage, where it can easily be disconnected from.
Wing structure is conventional composites, 2 spars, sandwich cored skin panels, drag spar should take all forces of flaperon.
I also want negative (upwards) flap deflection, and quite a lot of it, being 15-20 degrees, maybe a bit more. This seems as the ideal speed brake for high velocity descents. It lowers maximum lift and thus avoids structural overloads (Clmax about 0.5, dcl/dalpha is also flatter), causes a big rise in drag and doesn't require any extra "stuff", or power. I realize it reduces roll rate by an enormous amount, but above 200 kts, I guess I'll still have plenty of it
Both ailerons and flaperons are strictly mechanical. Actuating forces in my speed range will be low enough to make that possible. A very nice feature of this is that one can use negative flaps during T/O and landing. By that, you have excellent aileron control (cross-wind), without any tendency to lift the wing. Also, the wing won't stall as soon (I'm designing a taildragger, which often stall their tips during low speeds on the ground). During an X-wind landing you're also able to put the landing gear on the ground, go full negative and have full weight on your wheels.
I'm aware of the limitations of flaperons. I've flown with them quite a lot and am convinced I can make it work just as well in a powered aircraft. Landing deflection shouldn't exceed roughly 30 degrees (down). The wider deflection limits are for the combination of full flap (negative or positive) and aileron deflection. Wing deflection is taken into account.
A logical approach seems to make the flaperons with a torque tube (composite) that can drive the whole flaperon and have a counterweight (flutter) on the inside of the fuselage. A torque tube is stiff enough to easily bear all mechanical forces, but flutter is a serious consideration. Flutter, where the tip of the flaperon turns around the tube and where the flow and eigenfrequentie of the torsional vibration of the tube match might be a problem (that can be solved by making the tube stiffer)
I opened this thread to think about the actual attachment of the flaperon to the wing. Billski had an interesting thread about this, which got me thinking about the hinging of the flaperon.
In Short
Fuselage-driven flaperon, with a torsion tube in the LE of it, how would you hinge it?
Since we're talking straight flap(erons), without a gap (in fact, sealed over by mylar), there're basically 4 options.
The first one is a bearing around the torque tube. I've no idea, but there should be available something to hinge it this way, like on the crankshaft of a piston engine?
The second one is to hinge it only on the outer and inner side of the wing. That's about 9' long and much simpler. But is this realistic?
The third one is to cut the torsion tube on 1 or 2 places, hinge it there (in the middle of the torsion tube, much like most other flaps/ailerons are hinged) and built a structure around it, to make it stiff enough torsionally.
The forth one is using a piano hinge on the lower side of the wing skin. I don't like the idea of screwing hinges on it, but full span carbon hinges sound like an interesting idea:
Manufacturer
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