Aero 242                                       EXAM 1 REVIEW                                     S99

  1. Airplane Drag
    1.  airfoil drag
    2. drag source& types: pressure, skin friction, profile, wave
    3. flat plate boundary layers
    4. transition to turbulence: Reynold's number
    5. boundary layer thicknesses
    6. skin friction coefficients
    7. effects of favorable/adverse pressure gradients
    8. separation & effect on drag
    9. drag divergence
    10. wetted areas Sw, drag area f & total parasite drag on an a/c
    11. induced drag
    12. the drag polar
  2. Wing Geometry
    1.  root & tip chords, taper ratio, aspect ratio, wing reference area
    2. mean geometric chord
  3. Propellers
    1. forces on blades
    2.  power, thrust, torque coefficients
    3. advance ratio
    4. pitch: fixed, variable; constant speed units
  4. Reciprocating Engines
    1.  Power available curves, charts
    2. flat plate boundary layer
    3. brake, shaft horsepower
    4. sfc
  5. Jet Engines
    1.  momentum equation
    2. mass flow equation
    3. pressure force term "on design"
    4.  thrust variation wth flight speed
    5. turbojet & turbofan charts
    6. tsfc
  6. Equations of Motion: Unaccelerated Flight
    1. Free-body sketch showing forces for steady climb/descent attitude
    2. Equations in L, D, T, W, theta, thrust angle
    3. Equations for straight & level flight
    4. Assumptions involved in c
  7. Level Unaccelerated Flight: Thrust Required (Tr)
    1.  T, W, L/D relation
    2. Minimum Tr condition
    3. (L/D)max flight
    4. Determination of flight speed V
    5. Thrust required curve (Tr vs V)
    6. CL and alpha variation with V on Treq curve
    7. Parasite & induced drag variation on curve
    8. Parasite/induced drag relation at minimum Tr: CDo=CDi
  8. Level Unaccelerated Flight: Power Required (Pr)
    1. Minimum Pr condition
    2. Power required curve (Pr vs V)
    3. Parasite & induced drag variation on curve
    4. Parasite/induced drag relation at minimum Tr: CDi=3CDo
    5. (L/D)max location on power required curve
  9. Level Unaccelerated Flight:  Jet Thrust (Ta) & Power available (Pa)
    1. Show on  Tr vs V & Pr vs V plots
    2. Full & partial throttle
    3. Maximum speed at full and partial throttle
    4. Minimum speed at full and partial throttle
    5. Stall speed location wrt  minimum speed
  10. Level Unaccelerated Flight:  Reciprocating Engine Power Available
    1. Power units
    2. Shaft power/ brake power/ propeller efficiency/power available relations
    3. Show on Pr vs V plot
    4. Maximum speed at full and partial throttle
    5. Minimum speed at full and partial throttle
    6. Stall speed location
  11. Level Unaccelerated Flight:  Altitude Effects
    1.  V vs density relation (cf EAS)
    2. Pr vs density relation
    3. Show on P vs V plot