Aerodynamics and Flow Control in Aircraft Design: Mathematical
Problems for Performance Optimization
1. What is the lift coefficient (CL) of an aircraft wing with a lift force of 150,000 N, air density of 1.225
kg/m³, velocity of 100 m/s, and wing area of 120 m²?
a) 0.85
b) 1.02
c) 1.23
d) 1.44
Answer: b) 1.02
2. Calculate the drag force on an aircraft with a drag coefficient (CD) of 0.03, air density of 1.1 kg/m³,
velocity of 250 m/s, and wing area of 150 m².
a) 15,468.75 N
b) 18,562.50 N
c) 20,625.00 N
d) 22,687.50 N
Answer: c) 20,625.00 N
3. What is the angle of attack (in degrees) for a wing with a lift coefficient of 0.8 and a lift-curve slope
of 0.1 per degree?
a) 6
b) 8
c) 10
d) 12
Answer: b) 8
4. Calculate the Reynolds number for an aircraft flying at 200 m/s with a characteristic length of 5 m
and kinematic viscosity of 1.5 × 10⁻⁵ m²/s.
a) 6.67 × 10⁷
b) 5.33 × 10⁷
c) 4.67 × 10⁷
d) 3.33 × 10⁷
Answer: a) 6.67 × 10⁷
5. What is the Mach number for an aircraft flying at 250 m/s at an altitude where the speed of sound
is 330 m/s?
a) 0.65
b) 0.72
c) 0.76
d) 0.82
Answer: c) 0.76
6. Calculate the dynamic pressure (in Pa) for an aircraft flying at 180 m/s with an air density of 0.9
kg/m³.
a) 12,960
b) 14,580
c) 16,200
d) 17,820
Answer: b) 14,580
7. What is the aspect ratio of a wing with a span of 30 m and an area of 100 m²?
a) 7.5
b) 8.5
c) 9.0
d) 9.5
Answer: c) 9.0
8. Calculate the induced drag coefficient for a wing with an aspect ratio of 8 and a lift coefficient of
0.6, assuming an efficiency factor of 0.9.
a) 0.0141
b) 0.0159
c) 0.0177
d) 0.0195
Answer: b) 0.0159
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
9. What is the thickness-to-chord ratio of an airfoil with a maximum thickness of 0.3 m and a chord
length of 2 m?
a) 0.10
b) 0.15
c) 0.20
d) 0.25
Answer: b) 0.15
10. Calculate the total pressure (in Pa) at a point in the flow where the static pressure is 95,000 Pa
and the dynamic pressure is 15,000 Pa.
a) 100,000
b) 105,000
c) 110,000
d) 115,000
Answer: c) 110,000
11. What is the lift-to-drag ratio for an aircraft with a lift coefficient of 0.8 and a drag coefficient of
0.04?
a) 15
b) 20
c) 25
d) 30
Answer: b) 20
12. Calculate the critical Mach number for an airfoil with a maximum local velocity of 330 m/s when
the freestream velocity is 250 m/s.
a) 0.72
b) 0.76
c) 0.80
d) 0.84
Answer: b) 0.76
13. What is the wetted area (in m²) of a cylindrical fuselage with a diameter of 4 m and a length of 30
m?
a) 351.86
b) 376.99
c) 402.12
d) 427.25
Answer: b) 376.99
14. Calculate the wing loading (in N/m²) for an aircraft with a weight of 250,000 N and a wing area of
120 m².
a) 1,850
b) 2,083
c) 2,316
d) 2,549
Answer: b) 2,083
15. What is the oswald efficiency factor for a wing with an induced drag coefficient of 0.02, a lift
coefficient of 0.8, and an aspect ratio of 9?
a) 0.85
b) 0.88
c) 0.91
d) 0.94
Answer: c) 0.91
16. Calculate the change in lift coefficient for a 5° increase in angle of attack, given a lift-curve slope
of 0.11 per degree.
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
17. What is the span efficiency factor for an elliptical wing with an induced drag coefficient of 0.015
and a lift coefficient of 0.6, given an aspect ratio of 8?
a) 0.95
b) 0.97
c) 0.99
d) 1.01
Answer: c) 0.99
18. Calculate the wave drag coefficient for a supersonic aircraft flying at Mach 1.5, given that the
zero-lift drag coefficient is 0.015 and the wave drag factor is 0.1.
a) 0.0225
b) 0.0300
c) 0.0375
d) 0.0450
Answer: c) 0.0375
19. What is the equivalent flat plate area (in m²) for an aircraft with a drag coefficient of 0.03 and a
wing area of 150 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
20. Calculate the pressure coefficient at a point on an airfoil where the local velocity is 280 m/s and
the freestream velocity is 250 m/s.
a) -0.21
b) -0.25
c) -0.29
d) -0.33
Answer: b) -0.25
21. What is the glide ratio for an aircraft with a lift-to-drag ratio of 18?
a) 16
b) 17
c) 18
d) 19
Answer: c) 18
22. Calculate the maximum lift coefficient for a wing with a stall angle of 15° and a lift-curve slope of
0.1 per degree.
a) 1.3
b) 1.4
c) 1.5
d) 1.6
Answer: c) 1.5
23. What is the induced angle of attack (in degrees) for a wing with a lift coefficient of 0.7, an aspect
ratio of 10, and an efficiency factor of 0.9?
a) 1.24
b) 1.41
c) 1.58
d) 1.75
Answer: b) 1.41
24. Calculate the skin friction coefficient for a flat plate with a Reynolds number of 10⁷, assuming
turbulent flow.
a) 0.00251
b) 0.00285
c) 0.00319
d) 0.00353
Answer: b) 0.00285
25. What is the chord length (in meters) of a wing with an area of 120 m² and a span of 30 m?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: b) 4.0
26. Calculate the form factor for a wing with a thickness-to-chord ratio of 0.12 and a maximum
thickness location at 30% chord.
a) 1.28
b) 1.34
c) 1.40
d) 1.46
Answer: b) 1.34
27. What is the lift-curve slope (per radian) for a thin airfoil in incompressible flow?
a) 2π
b) 3π
c) 4π
d) 5π
Answer: a) 2π
28. Calculate the critical Reynolds number for transition from laminar to turbulent flow on a flat
plate.
a) 3 × 10⁵
b) 5 × 10⁵
c) 7 × 10⁵
d) 9 × 10⁵
Answer: b) 5 × 10⁵
29. What is the drag divergence Mach number for an airfoil with a critical Mach number of 0.72?
a) 0.74
b) 0.76
c) 0.78
d) 0.80
Answer: c) 0.78
30. Calculate the change in lift coefficient for a flap deflection of 20°, given a flap effectiveness factor
of 0.6 and a 2D lift effectiveness of 0.9 per radian.
a) 0.34
b) 0.38
c) 0.42
d) 0.46
Answer: b) 0.38
31. What is the maximum lift-to-drag ratio for an aircraft with a minimum drag coefficient of 0.02 and
an Oswald efficiency factor of 0.85?
a) 22.5
b) 25.0
c) 27.5
d) 30.0
Answer: c) 27.5
32. Calculate the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.08 flying at
Mach 1.2.
a) 0.0128
b) 0.0144
c) 0.0160
d) 0.0176
Answer: c) 0.0160
33. What is the required thrust-to-weight ratio for an aircraft to maintain level flight at a lift-to-drag
ratio of 15?
a) 0.0556
b) 0.0667
c) 0.0778
d) 0.0889
Answer: b) 0.0667
34. Calculate the change in zero-lift angle of attack (in degrees) for an airfoil with a camber of 4%
chord.
a) -2.0
b) -2.5
c) -3.0
d) -3.5
Answer: c) -3.0
35. What is the span loading (in N/m) for an aircraft with a weight of 200,000 N and a wingspan of 40
m?
a) 4,500
b) 5,000
c) 5,500
d) 6,000
Answer: b) 5,000
36. Calculate the induced drag factor for a wing with an aspect ratio of 12 and an Oswald efficiency
factor of 0.9.
a) 0.0294
b) 0.0327
c) 0.0360
d) 0.0393
Answer: a) 0.0294
37. What is the dynamic pressure ratio across a normal shock wave at Mach 1.5?
a) 0.65
b) 0.70
c) 0.75
d) 0.80
Answer: b) 0.70
38. Calculate the lift coefficient for minimum drag for an aircraft with a zero-lift drag coefficient of
0.015 and an induced drag factor of 0.04.
a) 0.39
b) 0.43
c) 0.47
d) 0.51
Answer: b) 0.43
39. What is the wetted aspect ratio for a wing with a wetted area of 250 m² and a span of 35 m?
a) 4.5
b) 4.9
c) 5.3
d) 5.7
Answer: b) 4.9
40. Calculate the change in pitching moment coefficient for a 10° elevator deflection, given an
elevator effectiveness of 0.6 and a 2D pitching moment effectiveness of -0.8 per radian.
a) -0.084
b) -0.096
c) -0.108
d) -0.120
Answer: a) -0.084
41. What is the Prandtl-Glauert compressibility factor for an aircraft flying at Mach 0.8?
a) 1.33
b) 1.50
c) 1.67
d) 1.84
Answer: c) 1.67
42. Calculate the change in lift coefficient for a 5% increase in camber, given a camber effectiveness
factor of 2.0.
a) 0.08
b) 0.10
c) 0.12
d) 0.14
Answer: b) 0.10
43. What is the drag area (in m²) for an aircraft with a drag coefficient of 0.025 and a wing area of
180 m²?
a) 3.5
b) 4.0
c) 4.5
d) 5.0
Answer: c) 4.5
44. Calculate the critical Mach number for an airfoil with a maximum local velocity of 340 m/s when
the freestream velocity is 280 m/s.
a) 0.78
b) 0.82
c) 0.86
d) 0.90
Answer: b) 0.82
45. What is the aspect ratio of a wing with a span of 25 m and a mean aerodynamic chord of 2.5 m?
a) 8
b) 9
c) 10
d) 11
Answer: c) 10
46. Calculate the change in lift coefficient for a 15° trailing edge flap deflection, given a flap chord
ratio of 0.3 and a 2D lift effectiveness of 1.2 per radian.
a) 0.78
b) 0.84
c) 0.90
d) 0.96
Answer: c) 0.90
47. What is the wave drag coefficient for a wing with a thickness-to-chord ratio of 0.1 flying at Mach
1.3?
a) 0.0221
b) 0.0247
c) 0.0273
d) 0.0299
Answer: c) 0.0273
48. Calculate the induced drag coefficient for a wing with an aspect ratio of 7.5 and a lift coefficient
of 0.9, assuming an efficiency factor of 0.85.
a) 0.0321
b) 0.0357
c) 0.0393
d) 0.0429
Answer: b) 0.0357
49. What is the Reynolds number for a wing with a chord of 3 m, flying at 150 m/s in air with a
kinematic viscosity of 1.5 × 10⁻⁵ m²/s?
a) 2.5 × 10⁷
b) 3.0 × 10⁷
c) 3.5 × 10⁷
d) 4.0 × 10⁷
Answer: b) 3.0 × 10⁷
50. Calculate the change in zero-lift drag coefficient for a 20% increase in wetted area, assuming
turbulent flow.
a) 0.0036
b) 0.0040
c) 0.0044
d) 0.0048
Answer: b) 0.0040
51. What is the lift coefficient for an aircraft with a weight of 300,000 N, flying at 200 m/s, with a
wing area of 150 m² and air density of 1.1 kg/m³?
a) 0.45
b) 0.50
c) 0.55
d) 0.60
Answer: c) 0.55
52. Calculate the change in lift-to-drag ratio for a 10% reduction in skin friction coefficient.
a) 5%
b) 7%
c) 9%
d) 11%
Answer: b) 7%
53. What is the Oswald efficiency factor for a wing with an induced drag coefficient of 0.018
