I built a paper and drinking straw canard glider in the 7th grade for a class project. I took Flight Dynamics and Control in college, while obtaining my degree in aerospace engineering. Your misapplied intuition about arrows is not at all convincing. Simply, you do not know anything about the stability of aircraft.
EDIT: WalterBright edited his comment to add examples and commentary after the arrow example. IOW, he added:
> Or make a paper airplane and toss it backwards.
> Or buy a toy glider and launch it backwards.
> They are unstable.
after I replied. His original comment was just:
> Try shooting an arrow with the feathers in the front :-)
A shitty move. I'll only address the "launch it backwards" comment, as the remaining bits are even more idiotic.
A canard airplane is not simply a backwards airplane. The criterion for stable forward motion, in pitch, is that dCm/d_alpha is negative, where Cm is the moment coefficient, and alpha is the angle of attack, and that the center of gravity be ahead of the center of lift. A "reversed" airplane, in either conventional or canard configuration, would have the center of gravity behind (in the new direction of travel) the center of lift, and would therefore be unstable.
Yaw stability is obtained by the vertical stabilizer exerting a moment opposite to the current yaw, by virtue of being behind the center of gravity and center of lift and, when yawed, being angled toward the midline of the aircraft. This is why, on a canard craft, the vertical stabilizer(s) are at the wing tips, or behind the center of lift and center of mass. A reversed aircraft, in WalterBright's imagination, or at his desk--It is difficult to trust anything he says, at this point.-- would have its vertical stabilizer ahead of the centers of lift and mass, and therefore destabilize the aircraft.
These two, that the center of mass is behind of the center of lift in the reversed configuration, and that the vertical stabilizer are ahead of it, are the actual reasons that WalterBright's toy glider, surprise, prefers to fly in the direction for which it was designed.
(He mentions the glider at his desk in his reply to this comment, which I will reproduce here, in case he deletes it: "I have a glider in my office. I launched it backwards. It promptly flipped over and proceeded in the normal direction.")
It would be interesting if, for example, WalterBright could produce a discussion from, say, Aerodynamics, Aeronautics, and Flight Mechanics, by Barnes W. McCormick, for example, warning the unawares aeronautical engineer in training of the dangers of the supposedly unstable canard aircraft.
The discussion above is all elementary flight mechanics, of which WalterBright would be aware if he'd had any training, or any expertise. Contrary to his repetition, his intuition does not suffice, and will not overturn these facts.
EDIT: WalterBright edited his comment to add examples and commentary after the arrow example. IOW, he added:
> Or make a paper airplane and toss it backwards.
> Or buy a toy glider and launch it backwards.
> They are unstable.
after I replied. His original comment was just:
> Try shooting an arrow with the feathers in the front :-)
A shitty move. I'll only address the "launch it backwards" comment, as the remaining bits are even more idiotic.
A canard airplane is not simply a backwards airplane. The criterion for stable forward motion, in pitch, is that dCm/d_alpha is negative, where Cm is the moment coefficient, and alpha is the angle of attack, and that the center of gravity be ahead of the center of lift. A "reversed" airplane, in either conventional or canard configuration, would have the center of gravity behind (in the new direction of travel) the center of lift, and would therefore be unstable.
Yaw stability is obtained by the vertical stabilizer exerting a moment opposite to the current yaw, by virtue of being behind the center of gravity and center of lift and, when yawed, being angled toward the midline of the aircraft. This is why, on a canard craft, the vertical stabilizer(s) are at the wing tips, or behind the center of lift and center of mass. A reversed aircraft, in WalterBright's imagination, or at his desk--It is difficult to trust anything he says, at this point.-- would have its vertical stabilizer ahead of the centers of lift and mass, and therefore destabilize the aircraft.
These two, that the center of mass is behind of the center of lift in the reversed configuration, and that the vertical stabilizer are ahead of it, are the actual reasons that WalterBright's toy glider, surprise, prefers to fly in the direction for which it was designed.
(He mentions the glider at his desk in his reply to this comment, which I will reproduce here, in case he deletes it: "I have a glider in my office. I launched it backwards. It promptly flipped over and proceeded in the normal direction.")
It would be interesting if, for example, WalterBright could produce a discussion from, say, Aerodynamics, Aeronautics, and Flight Mechanics, by Barnes W. McCormick, for example, warning the unawares aeronautical engineer in training of the dangers of the supposedly unstable canard aircraft.
The discussion above is all elementary flight mechanics, of which WalterBright would be aware if he'd had any training, or any expertise. Contrary to his repetition, his intuition does not suffice, and will not overturn these facts.