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6 Questions

Questions 6

Questions

1.What is the effect on total drag of an aircraft if the airspeed decreases in level flight below that speed for maximum L/D?

a.Drag increases because of increased induced drag.

b.Drag decreases because of lower induced drag.

c.Drag increases because of increased parasite drag.

d.Drag decreases because of lower parasite drag.

2.By changing the angle of attack of a wing, the pilot can control the aeroplane’s:

a.lift and airspeed, but not drag.

b.lift, gross weight, and drag.

c.lift, airspeed, and drag.

d.lift and drag, but not airspeed.

3.What is the relationship between induced and parasite drag when the gross weight is increased?

a.Parasite drag increases more than induced drag.

b.Induced drag increases more than parasite drag.

c.Both parasite and induced drag are equally increased.

d.Both parasite and induced drag are equally decreased.

4.In theory, if the airspeed of an aeroplane is doubled while in level flight, parasite drag will become:

a.twice as great.

b.half as great.

c.four times greater.

d.one quarter as much.

5.As airspeed decreases in level flight below that speed for maximum lift/drag ratio, total drag of an aeroplane:

a.decreases because of lower parasite drag.

b.increases because of increased parasite drag.

c.increases because of increased induced drag.

d.decreases because of lower induced drag.

6.(Refer to annex ‘A’) At the airspeed represented by point B, in steady flight, the aeroplane will:

a.have its maximum L/D ratio.

b.have its minimum L/D ratio.

c.be developing its maximum coefficient of lift.

d.be developing its minimum coefficient of drag.

134

 

 

Questions

 

6

 

7.

Which statement is true relative to changing angle of attack?

 

 

 

 

a.

A decrease in angle of attack will increase pressure below the wing, and

 

 

 

 

 

decrease drag.

 

 

 

 

b.

An increase in angle of attack will decrease pressure below the wing, and

 

 

 

 

 

increase drag.

 

 

 

 

c.

An increase in angle of attack will increase drag.

 

 

 

 

d.

A decrease in angle of attack will decrease pressure below the wing and

 

 

 

 

 

increase drag.

 

 

 

8.

On a wing, the force of lift acts perpendicular to, and the force of drag acts parallel

6

 

to the:

 

 

Questions

 

a.

flight path.

 

 

 

 

 

 

b.

longitudinal axis.

 

 

 

 

c.

chord line.

 

 

 

 

d.

longitudinal datum.

 

 

 

9.

That portion of the aircraft’s total drag created by the production of lift is called:

 

 

 

 

a.

induced drag, and is greatly affected by changes in airspeed.

 

 

 

 

b.

induced drag, and is not affected by changes in airspeed.

 

 

 

 

c.

parasite drag, and is greatly affected by changes in airspeed.

 

 

 

 

d.

parasite drag, which is inversely proportional to the square of the airspeed.

 

 

 

10.

The best L/D ratio of an aircraft occurs when parasite drag is:

 

 

 

 

a.

a minimum.

 

 

 

 

b.

less than induced drag.

 

 

 

 

c.

greater than induced drag.

 

 

 

 

d.

equal to induced drag.

 

 

 

11.

An aircraft has a L/D ratio of 15:1 at 50 kt in calm air. What would the L/D ratio be

 

 

 

 

with a direct headwind of 25 kt?

 

 

 

 

a.

30 : 1

 

 

 

 

b.

15 : 1

 

 

 

 

c.

25 : 1

 

 

 

 

d.

7.5 : 1

 

 

 

12.

Which is true regarding aerodynamic drag?

 

 

 

 

a.

Induced drag is a by product of lift and is greatly affected by changes in

 

 

 

 

 

airspeed.

 

 

 

 

b.

All aerodynamic drag is created entirely by the production of lift.

 

 

 

 

c.

Induced drag is created entirely by air resistance.

 

 

 

 

d.

Parasite drag is a by-product of lift.

 

 

 

13.

At a given True Airspeed, what effect will increased air density have on the lift and

 

 

 

 

drag of an aircraft?

 

 

 

 

a.

Lift will increase but drag will decrease.

 

 

 

 

b.

Lift and drag will increase.

 

 

 

 

c.

Lift and drag will decrease.

 

 

 

 

d.

Lift and drag will remain the same.

 

 

 

135

 

6

 

Questions

 

14.

If the Indicated Airspeed of an aircraft is increased from 50 kt to 100 kt, parasite

 

 

 

 

 

 

 

drag will be:

 

 

 

 

a.

four times greater.

 

 

 

 

b.

six times greater.

 

 

 

 

c.

two times greater.

 

 

 

 

d.

one quarter as much.

 

 

 

15.

If the Indicated Airspeed of an aircraft is decreased from 100 kt to 50 kt, induced

 

 

 

 

drag will be:

6

 

 

 

 

Questions

 

a.

two times greater.

 

b.

four times greater.

 

 

 

 

 

 

 

 

c.

half as much.

 

 

 

 

d.

one quarter as much.

 

 

 

16.

The best L/D ratio of an aircraft in a given configuration is a value that:

 

 

 

 

a.

varies with Indicated Airspeed.

 

 

 

 

b.

varies depending upon the weight being carried.

 

 

 

 

c.

varies with air density.

 

 

 

 

d.

remains constant regardless of Indicated Airspeed changes.

 

 

 

17.

The tendency of an aircraft to develop forces which restore it to its original

 

 

 

 

condition, when disturbed from a condition of steady flight, is known as:

 

 

 

 

a.

manoeuvrability.

 

 

 

 

b.

controllability.

 

 

 

 

c.

stability.

 

 

 

 

d.

instability.

 

 

 

18.

As Indicated Airspeed increases in level flight, the total drag of an aircraft becomes

 

 

 

 

greater than the total drag produced at the maximum lift/drag speed because of

 

 

 

 

the:

 

 

 

 

 

a.

decrease in induced drag only.

 

 

 

 

b.

increase in induced drag.

 

 

 

 

c.

increase in parasite drag.

 

 

 

 

d.

decrease in parasite drag only.

 

 

 

19.

The resistance, or skin friction, due to the viscosity of the air as it passes along the

 

 

 

 

surface of a wing is a type of:

 

 

 

 

a.

induced drag.

 

 

 

 

b.

form drag.

 

 

 

 

c.

parasite drag.

 

 

 

 

d.

interference drag.

 

 

 

20.

Which relationship is correct when comparing drag and airspeed?

 

 

 

 

a.

Parasite drag varies inversely as the square of the airspeed.

 

 

 

 

b.

Induced drag increases as the square of the airspeed.

 

 

 

 

c.

Parasite drag increases as the square of the lift coefficient divided by the

 

 

 

 

 

aspect ratio.

 

 

 

 

d.

Induced drag varies inversely as the square of the airspeed.

136

 

 

Questions

 

6

 

21.

If the same angle of attack is maintained in ground effect as when out of ground

 

 

 

 

effect, lift will:

 

 

 

 

a.

decrease, and parasite drag will decrease.

 

 

 

 

b.

increase, and induced drag will decrease.

 

 

 

 

c.

decrease, and parasite drag will increase.

 

 

 

 

d.

increase and induced drag will increase.

 

 

 

22.

Which statement is true regarding aeroplane flight at L/Dmax?

 

 

 

 

a.

Any angle of attack other than that for L/Dmax increases parasite drag.

6

 

b.

Any angle of attack other than that for L/Dmax increases the lift/drag ratio.

 

Questions

 

c.

Any angle of attack other than that for L/Dmax increases total drag for a

 

 

 

 

 

 

 

given aeroplane’s lift.

 

 

 

 

d.

Any angle of attack other than that for L/Dmax increases the lift and reduces

 

 

 

 

 

the drag.

 

 

 

23.

Aspect ratio of a wing is defined as the ratio of the:

 

 

 

 

a.

square of the chord to the wingspan.

 

 

 

 

b.

wingspan to the wing root.

 

 

 

 

c.

area squared to the chord.

 

 

 

 

d.

wingspan to the mean chord.

 

 

 

24.

A wing with a very high aspect ratio (in comparison with a low aspect ratio wing)

 

 

 

 

will have:

 

 

 

 

a.

poor control qualities at low airspeeds.

 

 

 

 

b.

increased drag at high angles of attack.

 

 

 

 

c.

a lower stall speed.

 

 

 

 

d.

reduced bending moment on its attachment points.

 

 

 

25.

At a constant velocity in airflow, a high aspect ratio wing will have (in comparison

 

 

 

 

with a low aspect ratio wing):

 

 

 

 

a.

increased drag, especially at a low angle of attack.

 

 

 

 

b.

decreased drag, especially at a high angle of attack.

 

 

 

 

c.

increased drag, especially at a high angle of attack.

 

 

 

 

d.

decreased drag, especially at low angles of attack.

 

 

 

26.

(Refer to annex ‘B’) Which aircraft has the highest aspect ratio?

 

 

 

 

a.

3.

 

 

 

 

b.

4.

 

 

 

 

c.

2.

 

 

 

 

d.

1.

 

 

 

27.

(Refer to annex ‘B’) Which aircraft has the lowest aspect ratio?

 

 

 

 

a.

4.

 

 

 

 

b.

2.

 

 

 

 

c.

3.

 

 

 

 

d.

1.

 

 

 

137

 

6

 

Questions

 

28.

(Refer to annex ‘B’) Consider only aspect ratio (other factors remain constant).

 

 

 

 

 

 

 

Which aircraft will generate greatest lift?

 

 

 

 

a.

1.

 

 

 

 

b.

2.

 

 

 

 

c.

3.

 

 

 

 

d.

4.

 

 

 

29.

(Refer to annex ‘B’) Consider only aspect ratio (other factors remain constant).

 

 

 

 

Which aircraft will generate greatest drag?

6

 

 

 

 

Questions

 

a.

1.

 

b.

4.

 

 

 

 

 

 

 

 

c.

3.

 

 

 

 

d.

2.

 

 

 

30.

What happens to total drag when accelerating from CLMAX to maximum speed?

 

 

 

 

a.

Increases.

 

 

 

 

b.

Increases then decreases.

 

 

 

 

c.

Decreases.

 

 

 

 

d.

Decreases then increases.

 

 

 

31.

(Refer to annex ‘C’), the whole aircraft CL against CD polar. Point ‘B’ represents:

1.Best Lift/Drag ratio.

2 .

The critical angle of attack.

3.Recommended approach speed.

4.Never exceed speed (VNE ).

a.1 and 2.

b.1 only.

c.2 and 3.

d.4 only.

32.If the Indicated Airspeed of an aircraft in level flight is increased from 100 kt to

200kt, by what factor will (i) TAS (ii) CDi (iii) Di change?

 

(i)

(ii)

(iii)

a.

2

1/4

1/16

b.

0

4

16

c.

4

1/16

1/4

d.

2

1/16

1/4

138

Questions 6

Annex A

Questions 6

Annex B

Aircraft 1. Span 22.5 metres

Chord 4 metres

Aircraft 2. Wing Area 90 square metres

Span 45 metres

Aircraft 3. Span 30 metres

Chord 3 metres

Aircraft 4. Wing Area 90 square metres

Span 40 metres

139

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