Four forces acting on an airplane Lift Weight Thrust Drag Elements of an airfoil Leading edge Trailing edge Upper camber Lower camber Chord line Angle of attack Any surface such as a wing, rotor blade or propeller which produces an aerodynamic force when it passes through a stream of air Airfoil Characteristic curve of the aerofoils upper and lower surfaces Camber Describes a convex sruface Positive camber Describes a concave surface Negative camber Low speed wing generally have a _____ camber Large, positive High speed wings generally have a ______ camber Small, positive AOA Angle of chord line in relation to the relative wind Describe the relation b/t AOA, lift, and velocity Lift = V2 (AOA) Straight and level, unaccelerated flight; Maintaining altitude and constant speed Equilibrium Aerodynamic stall Exceeding the critical AOA What do you need to enter a spin Stall and Yaw Controlling lift Aircraft design Pilot - change angle of attack, airspeed, shape of wing 4 types of flaps Plain Split Fowler Slotted Rear portion or airfoil rotates downwards on a simple hinge mounted at the front of the flap Plain flap Rear portion of the lower surface of the airfoil hinges downwards from the leading edge of the flap, while the upper surface stays immobile Split flap Slides backwards flat, before hinging downwards, thereby increasing first chord, and then camber Fowler flap Gap between the flap and the wing forces high pressure air from below the wing over the flap helping the airflow remain attached to the flaps, increasing lift compared to a split flap Slottted flap The separation of airflow from the airfoil resulting in the loss of lift Stall Explain stall recovery Decrease angle of attack Smoothly apply max power Adjust power as needed Recover to level flight Aggravated stall resulting in corkscrew path; One wing more stalled than the other Spin Load factor ratio` Load supported by the wings to Actual weight of the aircraft and contents Load factor ________ as angle of bank increase Increases Increasing lead factor will cause an airplane to... Stall at a higher speed Stalls that occur with G-forces being applied Accelerated stalls Maneuvering speed Va Force = Mass X acceleration Turning tendencies Torque Gyroscopic Precession Asymmetrical thrust Spiraling slipstream Example of torque Propeller rotates clockwise causing torque which tends to rotate the airplane counterclockwise about the longitudinal axis Gyroscopic precession Bike tire example Asymmetrical thrust (P-factor) More thrust on the right resulting in left yaw Spiraling slipstream Slipstream from propeller wraps around fuselage and hits left side of vertical fin (causes nose to yaw left) Any aircraft surface that interferes with the smooth flow of air around an airplane Parasite drag Three types of parasite drag Interference drag Form drag Skin friction drag Produced by the shape of the object moving through the air Form drag Interaction of varied currents that flow over an airplane and mix together Interference drag Roughness of airplane surfaces Skin friction drag Drag created by the production of lift Induced drag Total drag = Parasite + Induced Distance aircraft will travel forward, without power, in relation to altitude loss Glide ratio Angle between glide path and horizon Glide angle Phenomenon of less induced drag close to the ground Ground effect (pocket of air) Causes and airplane to turn Horizontal component of lift Three axes of rotation Longitudinal axis (ailerons) Lateral axis (Elevators) Vertical axis (rudder) Adverse yaw In a turn, outside wing produces more lift, causing yaw toward the outside of turn Airframe, engines, and all items of operating equipment that have fixed locations and are permanently installed in the aircraft Standard empty weight Weight of the pilot, passengers, baggage, usable fuel, and drainable fuel Useful load Total weight of loaded aircraft, includes all fuel Maximum ramp weight Maximum allowable weight for takeoff Maximum takeoff weight AVGAS weight 6lbs/Gal Aviation Oil weight 7.5lbs/Gal A point along the wing chord line where lift is considered to be concentrated. Center of Pressure (commonly called center of lift) Explain ground effect Interference of the surface of the earth with the airflow patterns about the aircraft in flight Occurs when both wings are stalled and there is a yawing moment due to uncoordinated flight. Spin A center-seeking force directed inward toward the center of rotation Centripetal force How is centripetal force created? Horizontal component of lift in turning flight Explain centrifugal force Pulling G's (force that pushes you into your seat) Centrifugal force less that horizontal component of lift Slipping turn Centrifugal force more than horizontal lift Skidding turn Turning flight causes two additional forces to occur Adverse yaw and overbanking Stability Aircraft's ability to resist change