1.
AVAF 209 Structures II <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>

2.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Aerodynamics: The study of objects in motion through the air and the forces that produce or change such motion

3.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul><ul><li>The Atmosphere </li></ul><ul><li>In order to fly, we need to create an upward force equal to the weight of the aircraft by using the Atmosphere </li></ul><ul><li>This force comes from the action of the atmosphere on an airfoil </li></ul>

4.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>Is made of a mixture of gases </li></ul><ul><ul><li>21% Oxygen </li></ul></ul><ul><ul><li>78% Nitrogen </li></ul></ul><ul><ul><li>Rest is mix of inert gases (Argon, Neon, etc.) </li></ul></ul>

5.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>Mixture remains constant regardless of altitude </li></ul><ul><li>Weight of air changes as altitude changes </li></ul><ul><ul><li>Less weight above as we go up = less ATMOSPHERIC PRESSURE exerted on objects </li></ul></ul>

6.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY CONDITIONS </li></ul><ul><ul><li>International Civil Aeronautics Organization (ICAO) has set standards for test data </li></ul></ul>

7.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY CONDITIONS </li></ul><ul><li>Allows comparison of test data from one location or day to any other in world </li></ul>

8.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>Is a force created by the weight of the atmosphere above an object </li></ul><ul><li>Is measured in IN-HG, MM-HG, PSI, or MILLIBARS </li></ul>

9.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>In-Hg or mm-Hg </li></ul><ul><ul><li>A tube is filled with Mercury (Hg) and then inverted in a container of Mercury </li></ul></ul><ul><ul><li>Hg will rise and height is measured </li></ul></ul>

10.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>In-Hg or mm-Hg </li></ul><ul><ul><li>On a Standard Day at SEA LEVEL (zero altitude), the height will be 29.92 inches 29.92 in-Hg) or 760 millimeters (760 mm-Hg) </li></ul></ul>

11.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>In-Hg or mm-Hg </li></ul><ul><ul><li>This is called an ABSOLUTE SCALE measurement as a VACUUM will form in the top of the tube (= ABSOLUTE ZERO PRESSURE) </li></ul></ul>

12.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>Atmospheric pressure will decrease by approx. 1 in-Hg for every 1,000 feet increase in altitude </li></ul><ul><ul><li>Known as the LAPSE RATE </li></ul></ul>

13.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>An ALTIMETER measures absolute pressure and displays the result in Feet Above Sea Level (ASL) </li></ul><ul><li>Notice KOLLSMAN WINDOW (adjust to varying local conditions) </li></ul>

14.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>PSI </li></ul><ul><ul><li>Is a measurement of FORCE / AREA </li></ul></ul><ul><ul><li>The most common units are POUNDS PER SQUARE INCH </li></ul></ul>

15.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>PSI </li></ul><ul><ul><li>On a Standard Day at Sea Level, the atmosphere pushes on objects with a force of 14.69 pounds per square inch of area </li></ul></ul>

16.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>PSI </li></ul><ul><ul><li>Since ½ of the air in the atmosphere is below 18,000 feet ASL, the pressure there is 7.34 psi </li></ul></ul>

17.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>PSI </li></ul><ul><ul><li>Is measured by an Absolute scale and is labeled PSIA </li></ul></ul>

18.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>Or a GAUGE scale which uses Atmospheric Pressure as the zero reference (= PSIG) </li></ul>

19.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Pressure </li></ul><ul><li>Millibars </li></ul><ul><ul><li>Are used by Meteorologists (weather forecasters) </li></ul></ul><ul><ul><li>Standard Day at Sea Level is 1013.2 mbs </li></ul></ul><ul><ul><li>1 millibar approximately equals .75 in-Hg </li></ul></ul>

20.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Temperature </li></ul><ul><li>Four scales used : </li></ul><ul><li>Celsius (used to be Centigrade) </li></ul>

21.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Temperature </li></ul><ul><li>Four scales used : </li></ul><ul><li>Kelvin (Absolute Celsius) </li></ul>

22.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Temperature </li></ul><ul><li>Four scales used : </li></ul><ul><li>Fahrenheit </li></ul>

23.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Temperature </li></ul><ul><li>Four scales used : </li></ul><ul><li>Rankine (Absolute Fahrenheit) </li></ul>

24.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Temperature </li></ul><ul><li>Standard Day at Sea Level: </li></ul><ul><ul><li>15 o Celsius </li></ul></ul><ul><ul><li>59 o Fahrenheit </li></ul></ul><ul><ul><li>288 0 Kelvin </li></ul></ul><ul><ul><li>519 o Rankine </li></ul></ul>

25.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Temperature </li></ul><ul><li>As we go up in altitude, temperature goes down </li></ul><ul><li>3.54 o F or 2 o C per 1,000 feet </li></ul><ul><li>ADIABATIC LAPSE RATE </li></ul>

26.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Humidity </li></ul><ul><li>Is amount of moisture in air </li></ul><ul><li>Measured by RELATIVE HUMIDITY </li></ul><ul><ul><li>Is comparison of moisture present to amount air can hold in percent </li></ul></ul><ul><ul><li>Maximum amount is directly proportional to temperature (hotter temp. = more moisture at same Relative Humidity %) </li></ul></ul>

27.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Humidity </li></ul><ul><li>Standard Day is 0% humidity or Dry Air </li></ul>

28.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density </li></ul><ul><li>Is measure of Mass per unit Volume </li></ul><ul><li>Mass is the amount of matter in an object </li></ul><ul><ul><li>Can think of it as number of molecules </li></ul></ul><ul><li>Weight is the affect of Gravity on a mass </li></ul><ul><ul><li>Since we are dealing with objects near the surface of the Earth, Weight and Mass are used interchangeably in Aerodynamics </li></ul></ul>

29.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density </li></ul><ul><li>Air density is officially measured in SLUGS PER CUBIC FOOT </li></ul><ul><ul><li>Standard Day at Sea Level = .002378 slugs/ft 3 </li></ul></ul><ul><ul><li>Formula symbol is the Greek letter Rho (  ) </li></ul></ul><ul><li>Is a major factor in developing Lift </li></ul><ul><li>Varies directly with Atmospheric Pressure and inversely with Temperature </li></ul>

30.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Aviation uses DENSITY ALTITUDE as important measure of density affects on flying </li></ul>

31.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Is a measure of an aircraft’s performance (necessary takeoff distance, necessary landing distance, weight-carrying capability, etc.) </li></ul>

32.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>“ The altitude in a Standard Day that has the same density as the Ambient conditions.” </li></ul><ul><li>Is the altitude the aircraft thinks it’s at </li></ul>

33.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Computed using a Density Altitude Chart </li></ul><ul><li>Must know PRESSURE ALTITUDE and Ambient Temperature </li></ul>

34.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Pressure Altitude is altitude in the Standard Day whose atmospheric pressure matches the local atmospheric pressure </li></ul>

35.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Press. Alt. Example: </li></ul><ul><ul><li>Ambient pressure of 28.92 in-Hg </li></ul></ul><ul><ul><li>Since pressure decreases 1 in-Hg/1000 feet, Pressure Altitude = 1,000 feet ASL </li></ul></ul>

36.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Dens. Alt. Example: </li></ul><ul><ul><li>Pressure Altitude can also be determined for the location you are by adjusting the Kollsman window to 29.92 and reading the altitude </li></ul></ul>

37.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Dens. Alt. Example: </li></ul><ul><ul><li>Pressure = 25.92 in-Hg (= ? feet Pressure Altitude) </li></ul></ul><ul><ul><li>= 4,000 feet </li></ul></ul><ul><ul><li>SL (29.92) – actual (25.92) = 4 inches x 1000 ft. </li></ul></ul>

38.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Dens. Alt. Example: </li></ul><ul><ul><li>Pressure = 25.92 in-Hg (= ? feet Pressure Altitude) </li></ul></ul><ul><ul><li>= 4,000 feet </li></ul></ul><ul><ul><li>Temperature = 80 o F </li></ul></ul>

39.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Dens. Alt. Example: </li></ul><ul><ul><li>Density Altitude = 6,500 feet </li></ul></ul>6,500

40.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Also is affected by the Relative Humidity </li></ul><ul><li>Water vapor has about 62% of weight of air = higher humidity = less dense air = higher Density Altitude </li></ul><ul><ul><li>= only affected by about 5% </li></ul></ul>

41.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Atmosphere <ul><li>STANDARD DAY </li></ul><ul><li>Density Altitude </li></ul><ul><li>Generally speaking: </li></ul><ul><li>BEWARE OF HIGH, HOT AND HUMID CONDITIONS </li></ul>

42.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Laws of Physics which affect Aerodynamics <ul><li>Bernoulli's Principle </li></ul><ul><ul><li>“ If the total energy of flowing air remains constant, any increase in KINETIC energy creates a decrease in POTENTIAL energy” </li></ul></ul><ul><ul><li>Since the LAW OF CONSERVATION OF ENERGY applies, the energies in the flow are only changed </li></ul></ul>

43.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Laws of Physics which affect Aerodynamics <ul><li>Bernoulli's Principle </li></ul><ul><li>Kinetic energy is measured as Velocity </li></ul><ul><li>Potential energy is measured as Pressure </li></ul>

44.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Laws of Physics which affect Aerodynamics <ul><li>Bernoulli's Principle </li></ul><ul><li>In “throat” of venturi: </li></ul><ul><li>Velocity goes up so all air gets through in same time = pressure down </li></ul>

45.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Laws of Physics which affect Aerodynamics <ul><li>Newton’s Laws </li></ul><ul><li>First Law: </li></ul><ul><ul><li>Law of Inertia </li></ul></ul><ul><ul><ul><li>A body at rest tends to remain at rest and a body in motion tends to remain in motion, until acted upon by an outside force. </li></ul></ul></ul>

46.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Laws of Physics which affect Aerodynamics <ul><li>Newton’s Laws </li></ul><ul><li>Second Law: </li></ul><ul><ul><li>Law of Acceleration </li></ul></ul><ul><ul><ul><li>Acceleration of a body is directly proportional to the force applied and inversely proportional to the mass of the body or a = F / m </li></ul></ul></ul><ul><ul><ul><li>Or more useful to us: F = ma </li></ul></ul></ul>

47.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Laws of Physics which affect Aerodynamics <ul><li>Newton’s Laws </li></ul><ul><li>Third Law </li></ul><ul><li>Law of Reaction </li></ul><ul><ul><ul><li>For every Action there is an Equal and Opposite Reaction </li></ul></ul></ul>

48.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>As we looked at before, there are four forces being applied to an airplane in flight: </li></ul><ul><ul><li>Lift (up) </li></ul></ul><ul><ul><li>Weight (down) </li></ul></ul><ul><ul><li>Thrust (forward) </li></ul></ul><ul><ul><li>Drag (aft) </li></ul></ul>

49.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>In order to understand these forces, we need to look at VECTORS: </li></ul>

50.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>A Vector is an arrow whose length shows a value and it points in the direction the value is being applied </li></ul>

51.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>To combine vectors, we place them with their starting points joined (as on the left below) </li></ul>

52.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>And by COMPLETING THE SQUARE we can get the RESULTANT vector (the combination of the other two) </li></ul>

53.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>If two forces are exactly opposing each other (such as Lift and Weight) and have the same value, the resultant is zero </li></ul>

54.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>In STRAIGHT AND LEVEL, UNACCELERATED FLIGHT, Thrust and Drag are equal, Lift and Weight are equal, and the aircraft continues in a straight line with no change in altitude </li></ul><ul><li>The forces are said to be in EQUILIBRIUM </li></ul>

55.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>In order to climb, we must increase the Lift Vector so there is no longer an equilibrium between Lift and Weight </li></ul><ul><li>The Resultant of the two is an upward force </li></ul>

56.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>In order to go faster (Accelerate), we must increase the Thrust vector to get a Resultant forward </li></ul><ul><li>Etc. </li></ul>

57.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Flight Forces </li></ul><ul><li>Thrust is created by the POWERPLANT and PROPELLER </li></ul><ul><li>Weight is the effect of Gravity on the aircraft </li></ul><ul><li>Drag is created by movement of the aircraft </li></ul><ul><li>Lift is created by the Airfoils used as Wings </li></ul>

58.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>An Airfoil is a specially designed surface which produces a reaction to air flowing across it </li></ul><ul><li>Two theories: </li></ul><ul><ul><li>Bernoulli’s Principle </li></ul></ul><ul><ul><li>Newton’s Laws </li></ul></ul>

59.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Subsonic airfoils can be Asymmetrical or Symmetrical </li></ul><ul><li>Most airplanes use Asymmetrical wings </li></ul><ul><ul><li>Blunt, rounded LEADING EDGE </li></ul></ul><ul><ul><li>Max. thickness about 1/3 of distance from L.E. to TRAILING EDGE </li></ul></ul>

60.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>There are many basic airfoil shapes </li></ul>

61.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>Early were very thin with definite camber </li></ul><ul><li>The Clark-Y was the standard through the 1930s </li></ul><ul><li>NACA developed the “modern” asymmetrical shape in the 30s and it was used for decades = smoother airflow and greater lift with less drag </li></ul><ul><li>There are many basic airfoil shapes </li></ul>

62.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>There are many basic airfoil shapes </li></ul><ul><li>As aircraft started to get near Mach 1, the subsonic shapes caused shock waves to form and destroy lift and increase drag tremendously </li></ul><ul><li>Supersonic airfoils were designed with sharp Leading and Trailing edges and the max thickness about ½ of the chord distance </li></ul>

63.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>There are many basic airfoil shapes </li></ul><ul><li>Next came the Supercritical design </li></ul><ul><ul><li>Reduces the velocity of the air over the upper surface and delays the drag rise occurring with the approach of Mach 1 </li></ul></ul><ul><li>NASA developed the GAW series for General Aviation aircraft and give higher lift with lesser drag than the “modern” </li></ul>

64.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>This is defined as the angle between the CHORD and the RELATIVE WIND (= opposite the FLIGHT PATH) </li></ul>

65.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>Don’t confuse this with the ANGLE OF INCIDENCE </li></ul><ul><ul><li>The angle formed between the Chord and the Longitudinal Axis of the airplane </li></ul></ul>

66.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>If the  is positive = the Leading Edge is higher than the Trailing Edge = generate Lift in the Upward direction </li></ul><ul><li>Negative  = downward Lift </li></ul>

67.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>As the  increases, the amount of Lift also increases </li></ul>Airfoil simulation

68.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>This can be shown graphically using the COEFFICIENT OF LIFT or C L </li></ul>

69.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>Notice the C L is positive even to a small negative  </li></ul>

70.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>And the C L peaks at some positive  </li></ul>

71.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>The Airfoil <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>Also, the C L starts to drop off if the  gets higher </li></ul><ul><li>This is called a STALL and starts at C Lmax or CRITICAL  </li></ul>

72.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>Stall is a SEPARATION OF AIRFLOW from the upper wing surface = rapid decrease in lift </li></ul>

73.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>This occurs at the same  regardless of speed, aircraft weight, or flight attitude </li></ul>

74.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>In order to generate Lift, an Airfoil must have an ANGLE OF ATTACK (  ) </li></ul><ul><li>To eliminate this condition = reduce the  below critical </li></ul>

75.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Airspeed </li></ul><ul><ul><li>Faster = increased Lift </li></ul></ul><ul><ul><li>Lift is increased as the square of the speed </li></ul></ul><ul><ul><li>For example: </li></ul></ul><ul><ul><ul><li>At 200 mph a wing has 4 times the lift of the same airfoil at 100 mph </li></ul></ul></ul><ul><ul><ul><li>At 50 mph the lift is ¼ as much as at 100 mph </li></ul></ul></ul>Airfoil simulation

76.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Wing Planform </li></ul><ul><ul><li>View of the wing from above or below </li></ul></ul>

77.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Wing Planform </li></ul><ul><li>Rectangular: excellent slow flight and stall occurs first at root of wing (= good aileron control) </li></ul>

78.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Wing Planform </li></ul><ul><li>Elliptical: most efficient = least drag for given size but difficult to manufacture and stalls all along Trail. Edge </li></ul>

79.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Wing Planform </li></ul><ul><li>Modified (or Moderate) Tapered: more efficient than Rectangular and easier to build than Elliptical but still stalls along Trailing Edge </li></ul>

80.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Wing Planform </li></ul><ul><li>SweptBack (and Delta): Good efficiency at high speed but not very good at low </li></ul>

81.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Camber </li></ul><ul><li>Curve of the wing </li></ul><ul><li>Increased Camber = increased airflow velocity over the top surface and more downwash angle = more lift </li></ul><ul><li>It also tends to lower the Critical  </li></ul><ul><li>Trailing Edge Flaps use this to allow more lift at a slower airspeed for landing and takeoff </li></ul>Airfoil simulation

82.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Aspect Ratio </li></ul><ul><li>Is the Ratio of the Wing’s SPAN to the average Chord </li></ul><ul><li>Higher Aspect Ratio (“long and skinny”) = increased lift and lower stalling speed </li></ul><ul><li>Used on Gliders and TR-1 spy plane </li></ul>

83.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Factors Affecting Lift: </li></ul><ul><li>Wing Area </li></ul><ul><li>Is the total surface area of the wings </li></ul><ul><li>Must be sufficient to lift max weight of the aircraft </li></ul><ul><ul><li>If wing produces 10.5 pounds of lift per square foot at normal cruise speed = needs Wing Area of 200 square feet to lift 2,100 pounds of weight </li></ul></ul>Airfoil simulation

84.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Drag </li></ul><ul><li>Is the force opposing Thrust </li></ul><ul><li>Is the force trying to hold the aircraft back as it flies and generally limits the maximum airspeed </li></ul><ul><li>Is created by any aircraft surface that deflects or interferes with the smooth air flow around the aircraft </li></ul><ul><li>Drag is classified as two types: </li></ul><ul><ul><li>Induced </li></ul></ul><ul><ul><li>Parasite </li></ul></ul>

85.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Induced Drag </li></ul><ul><li>The Airfoil shape (type of airfoil and amount of Camber) and Wing Area create a force which comes from the same forces as those which create Lift </li></ul><ul><li>It is Directly Proportional to the Angle of Attack (  ) </li></ul>

86.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Induced Drag </li></ul><ul><li>As  increases, the high pressure on the bottom of the wing flows around the wing tips and “fills in” some of the low pressure on top </li></ul><ul><li>This creates a WINGTIP VORTEX and destroys some of the wing’s lift or increases its drag </li></ul>

87.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Induced Drag </li></ul><ul><li>These can be dangerous for small aircraft flying behind a large aircraft </li></ul><ul><li>The strength of the Vortex is proportional to aircraft speed, weight, and configuration </li></ul>

88.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Induced Drag </li></ul><ul><li>This effect can be reduced by installing WINGLETS on the tips of the wings </li></ul><ul><ul><li>Reduce the Vortex = increased lift and reduced drag </li></ul></ul>

89.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Induced Drag </li></ul><ul><li>This effect can also be reduced by installing TIP TANKS on the tips of the wings </li></ul>

90.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Induced Drag </li></ul><ul><li>And/or by installing DROOPED TIPS </li></ul><ul><li>Used on STOL (Short Take Off/ Landing) aircraft or those designed for heavy and slow flight </li></ul>

91.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Induced Drag </li></ul><ul><li>This can also be shown by looking at the COEFFICIENT OF DRAG (C D ) of the airfoil </li></ul><ul><li>C D is proportional to Angle of Attack (  ) and increases as  increases </li></ul>

92.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Angle of Attack and Drag </li></ul><ul><li>By combining the C L and C D curves we get a “Family” of curves for any given airfoil </li></ul><ul><li>Includes a combination known as Lift-to-Drag Ratio (L/D) </li></ul>

93.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Angle of Attack and Drag </li></ul><ul><li>Peak L/D (L/D max ) occurs at a given  which is the most efficient  for the airfoil to operate at </li></ul>

94.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Angle of Attack and Drag </li></ul><ul><li>Unfortunately, this may be at too low an  to generate enough lift to fly (may not be able to fly fast enough) </li></ul>

95.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Parasite Drag </li></ul><ul><li>Is the drag produced by the aircraft itself and is proportional to Airspeed </li></ul><ul><li>Is disruption of the airflow around the aircraft </li></ul><ul><li>4 types: </li></ul><ul><ul><li>Form Drag </li></ul></ul><ul><ul><li>Skin Friction Drag </li></ul></ul><ul><ul><li>Interference Drag </li></ul></ul><ul><ul><li>Profile Drag </li></ul></ul>

96.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Parasite Drag </li></ul><ul><li>Form Drag </li></ul><ul><ul><li>Created by any structure which extends into the airstream </li></ul></ul><ul><ul><li>Is directly proportional to the size and shape of the structure </li></ul></ul><ul><ul><li>Includes struts, antennas, landing gear, etc. </li></ul></ul><ul><ul><li>Streamlining reduces Form Drag </li></ul></ul>

97.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Parasite Drag </li></ul><ul><li>Skin Friction Drag </li></ul><ul><ul><li>Caused by the roughness of the aircraft’s skin </li></ul></ul><ul><ul><ul><li>Includes paint, rivets, skin seams, etc. </li></ul></ul></ul><ul><ul><ul><li>Causes small swirls (eddies) of air = drag </li></ul></ul></ul><ul><ul><li>Improved by flush riveting and cleaning and waxing the skin </li></ul></ul>

98.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Parasite Drag </li></ul><ul><li>Interference Drag </li></ul><ul><ul><li>Occurs when various air currents around the aircraft structure intersect and interact with each other </li></ul></ul><ul><ul><ul><li>Example: mixing of air where fuselage and wings meet </li></ul></ul></ul><ul><ul><li>Improved by installing FAIRINGS </li></ul></ul>

99.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Parasite Drag </li></ul><ul><li>Profile Drag </li></ul><ul><ul><li>Drag formed by the Frontal Area of the aircraft </li></ul></ul><ul><ul><li>Can’t be changed or affected by anything except Retractable Landing Gear </li></ul></ul>

100.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Parasite Drag </li></ul><ul><li>Combined Parasite Drag Airspeed Effect </li></ul><ul><ul><li>Parasite Drag increases exponentially as airspeed increases </li></ul></ul><ul><ul><li>IS LOWEST AT LOW AIRSPEEDS and increases rapidly </li></ul></ul>

101.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Parasite Drag </li></ul><ul><li>Can best be reduced by Retractable Landing Gear & streamlining </li></ul><ul><li>Weight and complication is more than compensated by decrease in Parasite Drag at higher airspeeds </li></ul>

102.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Total Drag </li></ul><ul><li>Induced Drag is also somewhat dependent on Airspeed (indirectly) </li></ul><ul><li>Since it is Inversely Proportional to  and since the  is highest at low airspeeds = Induced Drag is highest at low airspeeds and drops off rapidly </li></ul>

103.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Total Drag </li></ul><ul><li>By combining the two Drag curves, we get Total Drag </li></ul><ul><li>At low airspeeds, Induced Drag predominates so curve goes down </li></ul><ul><li>At higher airspeeds, Parasite Drag predominates so curve goes up </li></ul>

104.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Total Drag </li></ul><ul><li>At some airspeed it will be at its lowest value = most efficient airspeed to fly at = best Lift/Drag Ratio or L/D max </li></ul><ul><li>However, like L/D max when looking at the  curve, it may not be possible to operate at this airspeed </li></ul>

105.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Other Design Considerations </li></ul><ul><li>Other factors affect the structure and design of an aircraft while in flight besides just Lift and Drag </li></ul><ul><li>These are: </li></ul><ul><ul><li>Load Factor </li></ul></ul><ul><ul><li>Propeller Factors </li></ul></ul><ul><ul><ul><li>Engine Torque </li></ul></ul></ul><ul><ul><ul><li>Gyroscopic Precession </li></ul></ul></ul><ul><ul><ul><li>Asymmetrical Thrust </li></ul></ul></ul><ul><ul><ul><li>Spiraling Slipstream </li></ul></ul></ul>

106.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Load Factor </li></ul><ul><li>Load Factor is a function of Banking an aircraft </li></ul><ul><li>You can also think of it as creating a curved flight path = CENTRIFUGAL FORCE puts more downward force (LOAD) on the structure </li></ul>

107.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Load Factor </li></ul><ul><li>So in order to maintain altitude = need to pull back on the yoke or stick and increase the engine’s power to increase the overall Lift component </li></ul>

108.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Load Factor </li></ul><ul><li>Load Factor is the Ratio of the load supported by the wings to the actual weight of the aircraft </li></ul><ul><li>Below about 20 o Bank Angle it is equal to 1G in force </li></ul><ul><ul><li>= the weight is not being increased </li></ul></ul>

109.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Load Factor </li></ul><ul><li>As the Bank Angle increases above that the “G-force” also goes up exponentially </li></ul><ul><li>For example: at about 60 o of Bank, the Load Factor is 2 </li></ul><ul><ul><li>The wings feel the aircraft weighs twice as much as normal </li></ul></ul>

110.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Load Factor </li></ul><ul><li>The FAA establishes LIMIT LOAD FACTORS for airplanes to be designed to </li></ul><ul><li>= the maximum Load Factor the aircraft can withstand without permanent deformation or structural damage </li></ul>

111.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Load Factor </li></ul><ul><li>For a NORMAL CATEGORY airplane = 3.8 positive Gs and 1.52 negative Gs </li></ul><ul><li>For a UTILITY CATEGORY = 4.4 positive Gs and 1.76 negative Gs </li></ul>

112.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Load Factor </li></ul><ul><li>For an ACROBATIC CATEGORY airplane = 6 positive Gs and 3 negative Gs </li></ul>

113.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Torque </li></ul><ul><li>Torque is a force applied to the airplane from the Reaction to the spinning Propeller (Newton’s 3 rd Law) </li></ul><ul><li>It causes a roll to the left = opposite of the normal rotation of U.S. designed engines </li></ul>

114.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Torque </li></ul><ul><li>On single-engine airplanes, it’s common to use aileron trim tabs to compensate </li></ul><ul><li>On multi-engine airplanes, it’s common for the engines to rotate in opposite directions which cancels out the Torque Effect </li></ul>

115.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Gyroscopic Precession </li></ul><ul><li>A rotating Propeller also acts like a GYROSCOPE and exhibits two gyroscopic characteristics: </li></ul><ul><ul><li>RIGIDITY IN SPACE </li></ul></ul><ul><ul><li>PRECESSION </li></ul></ul>

116.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Gyroscopic Precession </li></ul><ul><li>Precession is the phenomenon which says that any force applied to a Gyroscope is felt 90 o later in direction of rotation </li></ul>

117.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Gyroscopic Precession </li></ul><ul><li>Any rapid change in aircraft pitch = a precessive force applied to the prop. </li></ul><ul><ul><li>Most commonly felt by Conventional Gear airplanes just prior to Takeoff when the tail wheel is raised </li></ul></ul>

118.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Gyroscopic Precession </li></ul><ul><li>This causes a downward force (action) applied to the prop </li></ul><ul><li>Which causes a reaction 90 o later = yaw to the left </li></ul>

119.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Asymmetrical Thrust </li></ul><ul><li>At high aircraft angles of attack and during rapid climbs, the prop blades see differing angles of attack during their rotation </li></ul>

120.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Asymmetrical Thrust </li></ul><ul><li>The side of the prop “disk” on which the prop blade is descending has a higher  than the ascending blade = more lift </li></ul><ul><li>NOTE: rotation is clockwise as viewed from the pilot’s seat </li></ul>

121.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Asymmetrical Thrust </li></ul><ul><li>This change in  comes from the vertical movement and a corresponding change in Relative Wind of the airfoil </li></ul>

122.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Asymmetrical Thrust </li></ul><ul><li>Since the airfoil (prop) is rotating in addition to flying, the Relative Wind is now made of two factors: </li></ul>

123.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Asymmetrical Thrust </li></ul><ul><li>The Flight Path vector and a vertical (rotation) vector </li></ul><ul><li>Descending blade (right side) = vertical vector is down </li></ul>

124.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Asymmetrical Thrust </li></ul><ul><li>Which gives us a new Relative Wind and a higher  </li></ul>

125.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Asymmetrical Thrust </li></ul><ul><li>Since the descending (right) side of the prop has a higher  it is also producing more Thrust </li></ul><ul><li>The opposite occurs on the ascending side and it produces less Thrust </li></ul><ul><li>= tendency to yaw to left in rapid climb </li></ul>

126.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Spiraling Slipstream </li></ul><ul><li>On a single-engine airplane, the SLIPSTREAM from the propeller “wraps” itself around the fuselage in a Spiraling manner </li></ul><ul><li>It will generally then strike the left side of the Vertical Stabilizer and cause a yaw to the left </li></ul>

127.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Spiraling Slipstream </li></ul><ul><li>Since this is a function of how much air the prop is pushing which is directly proportional to the Thrust being produced = more yaw at higher power settings </li></ul>

128.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>Lift and Drag <ul><li>Propeller Factors: Spiraling Slipstream </li></ul><ul><li>It’s not uncommon to find the Vertical Stabilizer installed with a slight offset to the left to cause a constant compensating force </li></ul><ul><li>This is usually set up to balance the Slipstream affect during Cruise flight </li></ul>

129.
Basic Aerodynamics <ul><li>III. Basic Aerodynamics </li></ul><ul><ul><li>The Atmosphere </li></ul></ul><ul><ul><li>Physics </li></ul></ul><ul><ul><li>The Airfoil </li></ul></ul><ul><ul><li>Lift & Drag </li></ul></ul><ul><ul><li>Stability </li></ul></ul><ul><ul><li>Large Aircraft Flight Controls </li></ul></ul>