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:

    The role of the intelligence—that part of us which affirms and denies and formulates opinions—is merely to submit.
    Simone Weil (1909–1943)

    A famous theatrical actress
    Played best in the role of malefactress.
    Yet her home-life was pure
    Except, to be sure,
    A scandal or two just for practice.
    Anonymous.

    Whether talking about addiction, taxation [on cigarettes] or education [about smoking], there is always at the center of the conversation an essential conundrum: How come we’re selling this deadly stuff anyway?
    Anna Quindlen (b. 1952)

    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)