AVIT 323 Block 2 UPDATED Exam
Questions and CORRECT Answers
What is induced drag? - CORRECT ANSWER - The aft-acting component of lift
What are the two types of drag? - CORRECT ANSWER - Induced drag and Parasite Drag
What is a sphere of influence? - CORRECT ANSWER - Airflow that is affected by the
wing
What happens to induced drag as aspect ratio goes up? - CORRECT ANSWER -
Decreases
High aspect ratio changes the airflow minimally
What happens to induced drag as weight goes up? - CORRECT ANSWER - Increases by
the square
If lift (or weight) doubles, induced drag is 4 times as great.
What happens to induced drag as speed goes up? - CORRECT ANSWER - Decreases by
the square
Induced drag varies inversely as the square of airspeed
What happens to induced drag when you double the airspeed? - CORRECT ANSWER - It
decreases
The induced drag reduces to 1/4 the amount as before
What happens to induced drag when you cut the airspeed in half? - CORRECT
ANSWER - It increases... The induced drag multiplies by 4
What happens to induced drag as altitude goes up? - CORRECT ANSWER - Increases
Why are wingtip vortices included in induced drag? - CORRECT ANSWER - Induced
drag can be found when wingtip vortices are formed because they reduce the wing's ability to
create lift and increases the drag force acting on the aircraft
Define Viscosity - CORRECT ANSWER - Resistance to shear
, What are the types of Parasite Drag? - CORRECT ANSWER - Form Drag/Pressure Drag
Skin Friction Drag/Viscous
Profile Drag
Interference Drag
Cooling Drag
Leakage
Define boundary layer - CORRECT ANSWER - that layer of airflow over a surface that
demonstrates local airflow retardation due to viscosity.
What happens when the kinetic energy of a boundary layer equals zero? - CORRECT
ANSWER - It separates
Define adverse pressure gradient - CORRECT ANSWER - When static pressure increases
in the direction of the flow
Flow slows to point of reversing and separates from surface
What happens to the boundary layer during the adverse pressure gradient? - CORRECT
ANSWER - It weakens
What are two types of turbulent flow? - CORRECT ANSWER - Burbling (bad)
Vortex Tubes (good)
What are the three sections of a boundary layer? - CORRECT ANSWER - Laminar
(smooth)
Transition
Turbulent
Name two types of drag that increase as the boundary layer separates aft of the center of lift -
CORRECT ANSWER - Form Drag
Skin friction Drag/Viscous
What causes parasite drag? - CORRECT ANSWER - Forcing the airflow to change
directions
Questions and CORRECT Answers
What is induced drag? - CORRECT ANSWER - The aft-acting component of lift
What are the two types of drag? - CORRECT ANSWER - Induced drag and Parasite Drag
What is a sphere of influence? - CORRECT ANSWER - Airflow that is affected by the
wing
What happens to induced drag as aspect ratio goes up? - CORRECT ANSWER -
Decreases
High aspect ratio changes the airflow minimally
What happens to induced drag as weight goes up? - CORRECT ANSWER - Increases by
the square
If lift (or weight) doubles, induced drag is 4 times as great.
What happens to induced drag as speed goes up? - CORRECT ANSWER - Decreases by
the square
Induced drag varies inversely as the square of airspeed
What happens to induced drag when you double the airspeed? - CORRECT ANSWER - It
decreases
The induced drag reduces to 1/4 the amount as before
What happens to induced drag when you cut the airspeed in half? - CORRECT
ANSWER - It increases... The induced drag multiplies by 4
What happens to induced drag as altitude goes up? - CORRECT ANSWER - Increases
Why are wingtip vortices included in induced drag? - CORRECT ANSWER - Induced
drag can be found when wingtip vortices are formed because they reduce the wing's ability to
create lift and increases the drag force acting on the aircraft
Define Viscosity - CORRECT ANSWER - Resistance to shear
, What are the types of Parasite Drag? - CORRECT ANSWER - Form Drag/Pressure Drag
Skin Friction Drag/Viscous
Profile Drag
Interference Drag
Cooling Drag
Leakage
Define boundary layer - CORRECT ANSWER - that layer of airflow over a surface that
demonstrates local airflow retardation due to viscosity.
What happens when the kinetic energy of a boundary layer equals zero? - CORRECT
ANSWER - It separates
Define adverse pressure gradient - CORRECT ANSWER - When static pressure increases
in the direction of the flow
Flow slows to point of reversing and separates from surface
What happens to the boundary layer during the adverse pressure gradient? - CORRECT
ANSWER - It weakens
What are two types of turbulent flow? - CORRECT ANSWER - Burbling (bad)
Vortex Tubes (good)
What are the three sections of a boundary layer? - CORRECT ANSWER - Laminar
(smooth)
Transition
Turbulent
Name two types of drag that increase as the boundary layer separates aft of the center of lift -
CORRECT ANSWER - Form Drag
Skin friction Drag/Viscous
What causes parasite drag? - CORRECT ANSWER - Forcing the airflow to change
directions
