Aerodynamic Center - Role of Aerodynamic Center in Aircraft Stability

Role of Aerodynamic Center in Aircraft Stability

For longitudinal static stability: and

For directional static stability: and

Where:

For A Force Acting Away at the Aerodynamic Center, which is away from the reference point:

Which for Small Angles and =, simplifies to:

General Case: From the definition of the AC it follows that

.
.

The Static Margin can then be used to quantify the AC:

where:

= yawing moment coefficient
= pitching moment coefficient
= rolling moment coefficient
= X-force ~= Drag
= Y-force ~= Side Force
= Z-force ~= Lift
ref = reference point (about which moments were taken)
c = reference length
S = reference area
q = dynamic pressure
= angle of attack
= sideslip angle

SM = Static Margin

Read more about this topic:  Aerodynamic Center

Famous quotes containing the words role of, role, center and/or stability:

    But however the forms of family life have changed and the number expanded, the role of the family has remained constant and it continues to be the major institution through which children pass en route to adulthood.
    Bernice Weissbourd (20th century)

    Of course, some men are very effective caregivers [of elderly parents]. But this situation occurs far less frequently for males than females, because it is a role reversal. For women, caregiving is an expected duty; for men, it is an unexpected expression of love or devotion.
    Tish Sommers (20th century)

    Everything that explains the world has in fact explained a world that does not exist, a world in which men are at the center of the human enterprise and women are at the margin “helping” them. Such a world does not exist—never has.
    Gerda Lerner (b. 1920)

    No one can doubt, that the convention for the distinction of property, and for the stability of possession, is of all circumstances the most necessary to the establishment of human society, and that after the agreement for the fixing and observing of this rule, there remains little or nothing to be done towards settling a perfect harmony and concord.
    David Hume (1711–1776)