Directional Stability

Question 1

What is directional stability?

Answer 1

it is the stability around the VERTICAL or NORMAL AXIS

Question 2

the most important features that affects directional stability are..

Answer 2

vertical tail surface (fin and rudder)

keel effect and sweepback also contribute to directional stability

Question 3

How does the vertical tail help?

Answer 3

If the airplane yaws from its course the airflow strikes the vertical tail surface from the side and pushes it back to its original flight

Question 4

What must be done for the tail surface to function properly?

Answer 4

the side area of the plane close to the centre of gravity must be GREATER than the side area of the airplane forward of the C.G