14-11-2012, 05:42 PM
Advanced Aerodynamics
Airplane_Aerodynamics.ppt (Size: 200 KB / Downloads: 60)
Fundamental Flight Maneuvers
Straight and Level
Turns
Climbs
Descents
Four Aerodynamic Forces
Lift
Thrust
Drag
Weight
When are they in equilibrium?
In steady-state or unaccelerated straight and level flight
What happens when you initiate a climb?
Lift briefly exceeds weight.
Rearward component of the Lift adds to drag
Upward component of Thrust is called the Lift of Thrust
Lift
Second law of motion says that a force results whenever a mass is accelerated F = ma
Third law states for every action there is an equal and opposite reaction
Bernoulli’s Principle
As the velocity of a fluid increase, its internal pressure decreases
High pressure under the wing and lower pressure above the wing’s surface
Angle of Attack
Directly controls the distribution of pressure acting on a wing. By changing the angle of attack, you can control the airplane’s lift, airspeed and drag.
Angle of attack at which a wing stalls remains constant regardless of weight, dynamic pressure, bank angle or pitch attitude.
When the angle of attack of a symmetrical airfoil is increased, the center of pressure will remain unaffected.
At high angle of attack, pressure increases below the wing, and the increase in lift is accompanied by an increase in induced drag.
Wing Planform
Elliptical - Excellent load distribution for high-G maneuvering and low drag for high speeds
Rectangular - stall first at root, least expensive
Tapered - Favorable stall characteristics with good load distribution, saves weight
Delta - supersonic flight