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The lever arm of the empennage should be as large as possible. (Lever arm is the distance between the aerodynamic center of the wing and the horizontal stabilizer). This will reduce the size of the empennage, saving weight.
The aspect ratio of the horizontal stabilizer should be about half the aspect ratio of the
wing.Horizontal Stabilizer is fixed, an incidence angle of around 2° to 3° downwards
should be chosen to create a negative lift. (assuming we are using asymmetrical airfoil)Symmetrical airfoils are exclusively selected for vertical Stabilizer. (NACA 0004 0009 might be a good start)
Horizontal stabilizer