Avit 323 Block 10 Exam: Parasite Drag
Questions and Answers 100% Pass
drag definition - ✔✔the component of aerodynamic force that is parallel to the relative
wind and retards the forward motion of the aircraft
drag - ✔✔a result of the interaction and contact of a solid body with a fluid (liquid or
gas)
parasite drag - ✔✔-drag that is NOT associated with the production of lift
-the result of displacement of air by the aircraft
induced drag - ✔✔the portion of drag which is caused by the production of lift
shockwave drag - ✔✔result of shockwave formations at high speeds
types of parasite drag - ✔✔-skin friction
-form
-profile
-interference
-cooling
Brittie Donald, All Rights Reserved © 2025 1
, -leakage
skin friction drag - ✔✔-the aerodynamic resistance due to the contact of moving air
with the surface of the aircraft
-no matter how smooth a surface appears, every surface has rought and ragged surface
when viewed under a microscope
factors that influence skin friction - ✔✔-wetted surface
-amount of viscous drag in the boundry layer
-velocity
wetted area - ✔✔portion of the aircraft that is in direct contact with the atmosphere
what is the boundary layer? - ✔✔airflow which shows local reduction in airflow due to
viscosity
what are the two types of boundary layers? - ✔✔laminar and turbulent
Laminar boundary layer - ✔✔-low viscous drag
-seperations occurs earlier
turbulent boundary layer - ✔✔-high viscous drag
-seperation occurs later
reducing skin friction - ✔✔-flush mounted rivets
Brittie Donald, All Rights Reserved © 2025 2
Questions and Answers 100% Pass
drag definition - ✔✔the component of aerodynamic force that is parallel to the relative
wind and retards the forward motion of the aircraft
drag - ✔✔a result of the interaction and contact of a solid body with a fluid (liquid or
gas)
parasite drag - ✔✔-drag that is NOT associated with the production of lift
-the result of displacement of air by the aircraft
induced drag - ✔✔the portion of drag which is caused by the production of lift
shockwave drag - ✔✔result of shockwave formations at high speeds
types of parasite drag - ✔✔-skin friction
-form
-profile
-interference
-cooling
Brittie Donald, All Rights Reserved © 2025 1
, -leakage
skin friction drag - ✔✔-the aerodynamic resistance due to the contact of moving air
with the surface of the aircraft
-no matter how smooth a surface appears, every surface has rought and ragged surface
when viewed under a microscope
factors that influence skin friction - ✔✔-wetted surface
-amount of viscous drag in the boundry layer
-velocity
wetted area - ✔✔portion of the aircraft that is in direct contact with the atmosphere
what is the boundary layer? - ✔✔airflow which shows local reduction in airflow due to
viscosity
what are the two types of boundary layers? - ✔✔laminar and turbulent
Laminar boundary layer - ✔✔-low viscous drag
-seperations occurs earlier
turbulent boundary layer - ✔✔-high viscous drag
-seperation occurs later
reducing skin friction - ✔✔-flush mounted rivets
Brittie Donald, All Rights Reserved © 2025 2
