Aerodynamics Controls Examination

1. What is the purpose of the trim tabs on control surfaces?
   a. To reduce control surface effectiveness
   b. To relieve control pressure and maintain a desired flight condition
   c. To assist with roll control
   d. To increase the aircraft’s maximum speed

1. On what instance does negative pressure coefficient occurs?
   a. When dynamic pressure is twice the pressure difference
   b. When the freestream velocity is higher than local velocity
   c. When local velocity is higher than freestream velocity
   d. When dynamic pressure is twice the pressure difference

1. One example of __ is the path defined by a balloon floating in
   the air.
   a. Streakline b. Pathline
   c. Curveline d. Streamline

1. What is the region behind a shockwave where the air has slowed
   down and the flow is subsonic again?
   a. Expansion fan b. Subsonic zone
   c. Transonic region d. Compression zone

1. What is a suitable flow model for a fluid?
   a. Finite control volume approach
   b. All the 3 models can be used based on the need
   c. Molecular approach
   d. Infinitesimal fluid element approach

1. Which of the following statements about stall speed is correct?
   a. Increasing the angle of sweep of the wing will decrease the stall
   speed
   b. Increasing the angle of sweep of the wing will decrease the stall
   speed
   c. Decreasing the angle of sweep of the wing will decrease the stall
   speed
   d. The use of a T-tail will decrease the stall speed

1. If all, or a significant part of a stall strip is missing on an airplane
   wing, a likely result will be
   a. Asymmetrical lateral control at low angles of attack
   b. Decreased lift in the area of installation at high angles of attack
   c. Symmetrical lateral control at high angles of attack
   d. Asymmetrical lateral control at or near stall angles of attack

1. Translational thrust occurs when…
   a. the tail rotor becomes less aerodynamically efficient during the
   transition from hover to forward flight.
   b. the tail rotor becomes more aerodynamically efficient during the
   transition from hover to forward flight.

Answers:

1. B
2. C
3. B
4. A
5. B
6. C
7. D
8. B
9. B
10. C

1. How does the wake turbulence vortex circulate around each
   wingtip?
   a. Outward, upward, and around each tip.
   b. Inward, upward, and around each tip.
   c. Inward, upward, and around each tip.
   d. From the tip, upward, and inward.

2. If the power available is assumed to be independent of flight speed,
the maximum rate of climb occurs when
a. The excess power remains constant
b. The power required is minimum
c. The excess power is minimum
d. The power required is maximum

3. Which part of the airplane provides the greatest positive
contribution to the static longitudinal stability?
a. Horizontal stabilizer b. The engine
c. The fuselage d. The engine

4. The tendency of an aircraft to ‘weathercock’ into the wind to
maintain directional equilibrium.
a. Directional static stability
b. Lateral static stability
c. Lateral static stability
d. Static stability

5. During a spin to the left, which wing(s) is/are stalled?
a. Right wing
b. Neither of the wings
c. Left wing
d. Both wings are stalled

6. Equivalent skin friction coefficient may include __.
a. only skin friction drag
b. only wave drag
c. only skin friction drag
d. skin friction and separation drag

7. What is the purpose of using flaps during takeoff and landing?
a. To control pitch
b. To decrease fuel consumption
c. To increase lift and drag
d. To control yaw

8. __ is the slowing down of the air after it has left the working
section.
a. Converging b. Diffusion
c. Converging d. Choking

9. Which parameter does the Prandtl-Meyer expansion fan depend on?
a. Temperature b. Wing loading
c. Altitude d. Mach number

10. Which of the following flow is practically impossible in nature?
a. Laminar flow b. Laminar flow
c. Viscous flow d. Inviscid flow

11. Turbulent flow is characterized by:
a. High viscosity of the fluid
b. Smooth and regular fluid motion
c. High viscosity of the fluid
d. Chaotic and unpredictable fluid motion

Asnwers:

1. A
2. B
3. A
4. A
5. D
6. D
7. C
8. B
9. D
10. D
11. D