13-14 - The Whole Aircraft Drag

Question 1

What is interference drag

Answer 1

When the molecules have to move around the shape of the aircraft

Question 2

Form drag + skin drag =

Answer 2

Profile drag

Question 3

Factors affecting form drag

Answer 3

Airspeed
Frontal area
Shape and streamlining
Surface- smooth = wide wake turbulence

Question 4

Factor affecting skin friction drag

Answer 4

Speed
Surface area
Boundary layer conditions- a turbulent boundary layer = more skin friction drag
Surface roughness-rough surface causes a turbulent boundary layer

Question 5

,factors affecting parasite drag

Answer 5

Air speed-ias squared is proportional to parasite drag
Flaps

Question 6

Factor affecting the coefficient of parasite drag

Answer 6

Streamlining
Surface roughness
Presence of fillets (fairings)

Question 7

Factors affecting induced drag

Answer 7

Weight
Speed
Manoeuvre
Aspect ratio-inversely prop

Question 8

Cdi is a measure of what

Answer 8

Downwash (induced aoa)

Question 9

How to reduce included drag

Answer 9

Tip modifications