POF Q10 - Total Drag and the Drag Polar

Question 1

The aerofoil polar is:
Select one

a.a graph of the relation between Lift and Drag

b.a graph of the relation between the lift coefficient and the angle of attack

c.a graph, in which the thickness of the wing aerofoil is given as a function of the chord

d.a graph of the relation between the lift coefficient and the drag coefficient

Answer 1

d.a graph of the relation between the lift coefficient and the drag coefficient

Question 2

The polar curve of an aerofoil is a graphic relation between:
Select one

a.TAS and stall speed

b.CL and CD

c.CD and angle of attack

d.Angle of attack and CL

Answer 2

b.CL and CD

Question 3

Comparing the lift coefficient and drag coefficient at normal angle of attack:
Select one

a.CL has approximately the same value as CD

b.CL is much greater than CD

c.CL is much lower than CD

d.CL is lower than C

Answer 3

b.CL is much greater than CD

Question 4

Which one of the following statements about the L/D ratio in straight and level flight is correct?
Select one

a.The highest value of the L/D ratio is reached when the lift is equal to the aircraft weight

b.The L/D ratio always increases as the lift decreases

c.The highest value of the L/D ratio is reached when the lift is zero

d.At the highest value of the L/D ratio the total drag is lowest

Answer 4

d.At the highest value of the L/D ratio the total drag is lowest

Question 5

Increasing dynamic pressure will have the following effect on the drag of an aeroplane (all other factors of importance remaining constant):
Select one

a.drag increases across the whole speed range

b.none

c.drag decreases across the whole speed range

d.at speeds greater than the minimum drag speed, drag increases

Answer 5

d.at speeds greater than the minimum drag speed, drag increases

Question 6

In what way do (1) induced drag and (2) parasite drag alter with increasing speed in straight and level flight?
Select one:

a.(1) decreases and (2) decreases

b.(1) increases and (2) decreases

c.(1) increases and (2) increases

d.(1) decreases and (2) increases

Answer 6

d.(1) decreases and (2) increases

Question 7

What happens to your VMD speed (as a TAS) with increasing pressure altitude?
Select one:

a.Decreases

b.Remains constant

c.Increases

d.Increases then decreases

Answer 7

c.Increases

Question 8

An aircraft suffers a disturbance in speed. The pilot finds that the speed continues to displace further from the original speed. Where on the drag curve is this aircraft?
Select one:

a.Speed stable range

b.VMD

c.Speed neutral range

d.Speed unstable range

Answer 8

d.Speed unstable range

Question 9

Which statement is correct?
Select one:

a.VMD is found in the speed neutral range

b.VMD is found in the speed stable range

c.VMD increases with an increase in speed

d.VMD is found In the speed unstable range

Answer 9

a.VMD is found in the speed neutral range

Question 10

Name The correct parts of the Drag Polar graph

Answer 10

CLMAX

CL/CDMax

CDP…………….CDP + CD