Free CAAS SAR-66 M08 Basic Aerodynamics Practice Questions

Sample Practice Questions

Try these 10 sample questions from the CAAS SAR-66 M08 Basic Aerodynamics practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1Why is a standard atmosphere used when comparing aircraft performance?

   1. A.It reproduces the weather expected at every airport.
   2. B.It provides a common reference for evaluating performance.Correct answer: B
   3. C.It removes the effect of altitude on aircraft performance.
   4. D.It specifies the maximum temperature allowed for flight.

   Explanation: The FAA states, "Since aircraft performance is compared and evaluated with respect to the standard atmosphere, all aircraft instruments are calibrated for the standard atmosphere." The model supplies a common reference; actual conditions still vary.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Principles of Flight — Principles of Flight — standard-atmosphere comparison immediately before Pressure Altitude

2. 2Which line is the chord line of an aerofoil section?

   1. A.A curved line following the upper aerofoil surface
   2. B.A straight line connecting the leading and trailing edgesCorrect answer: B
   3. C.A curved line equidistant from the upper and lower surfaces
   4. D.A straight line joining the two wingtip extremities

   Explanation: The FAA states, "the chord line, a straight line drawn through the profile connecting the extremities of the leading and trailing edges." The chord joins the section's leading and trailing edges; the camber line, upper contour and spanwise line are different references.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Principles of Flight — Airfoil Design

3. 3An aeroplane maintains straight, level, unaccelerated flight, with thrust parallel to the flight path. Which force relationship applies?

   1. A.Lift equals drag, and thrust equals weight.
   2. B.Lift exceeds weight, and thrust equals drag.
   3. C.Lift equals weight, and thrust equals drag.Correct answer: C
   4. D.Lift equals weight, and thrust exceeds drag.

   Explanation: The FAA gives the familiar relationship "thrust equals drag and lift equals weight." Here the stated straight, level, unaccelerated conditions and flight-path-parallel thrust make both opposing pairs balance. All four forces need not have the same magnitude.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Aerodynamics of Flight — Forces Acting on the Aircraft

4. 4Which aircraft motion is the concern of longitudinal stability?

   1. A.Rolling about the longitudinal axis
   2. B.Pitching about the lateral axisCorrect answer: B
   3. C.Yawing about the vertical axis
   4. D.Rolling about the lateral axis

   Explanation: The FAA states, "Longitudinal stability is the quality that makes an aircraft stable about its lateral axis." Longitudinal stability governs pitch. Roll about the nose-to-tail axis is lateral stability, and yaw about the vertical axis is directional stability.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Aerodynamics of Flight — Longitudinal Stability (Pitching)

5. 5What is the standard-atmosphere temperature at mean sea level?

   1. A.0 °C
   2. B.10 °C
   3. C.15 °CCorrect answer: C
   4. D.25 °C

   Explanation: The reference is a "surface temperature of 59 °F or 15 °C". Thus 15 °C is the sea-level standard; the other temperatures represent different reference or actual conditions.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Principles of Flight — Atmospheric Pressure

6. 6Which description identifies the mean camber line of an aerofoil?

   1. A.The straight line between leading and trailing edges
   2. B.The contour traced along the lower aerofoil surface
   3. C.The curved line traced along the upper aerofoil surface
   4. D.The line equidistant from the upper and lower surfacesCorrect answer: D

   Explanation: The FAA states, "This mean line is equidistant at all points from the upper and lower surfaces." Equidistance distinguishes the mean camber line from the chord and surface contours.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Principles of Flight — Airfoil Design

7. 7In straight level flight, thrust becomes greater than drag. Which statement correctly describes the longitudinal force balance?

   1. A.The forward resultant causes the aeroplane to accelerate.Correct answer: A
   2. B.The drag force exactly cancels the greater thrust force.
   3. C.The aircraft's weight balances the forward thrust difference.
   4. D.The aircraft's inertia cancels the forward thrust difference.

   Explanation: The FAA states, "As long as the thrust continues to be greater than the drag, the aircraft continues to accelerate." The forward resultant accelerates the aircraft. Equal thrust and drag would be needed to maintain speed.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Aerodynamics of Flight — Thrust

8. 8Which motion is resisted by positive lateral stability?

   1. A.Pitching about the lateral axis
   2. B.Yawing about the vertical axis
   3. C.Pitching about the vertical axis
   4. D.Rolling about the longitudinal axisCorrect answer: D

   Explanation: The FAA states, "Stability about the aircraft’s longitudinal axis, which extends from the nose of the aircraft to its tail, is called lateral stability." Lateral stability refers to roll about the nose-to-tail axis, despite the apparent similarity between the word lateral and the lateral axis.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Aerodynamics of Flight — Lateral Stability (Rolling)

9. 9Which pressure is the standard sea-level reference used for pressure-altitude measurement?

   1. A.29.92 inches of mercuryCorrect answer: A
   2. B.28.92 inches of mercury
   3. C.30.92 inches of mercury
   4. D.31.92 inches of mercury

   Explanation: The FAA identifies "a surface pressure of 29.92 inches of mercury". The reference is fixed; a local pressure reading need not equal it.

   Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Principles of Flight — Atmospheric Pressure

10. 10Which two references define an aerofoil's angle of attack?

    1. A.The chord line and the relative windCorrect answer: A
    2. B.The fuselage axis and the geographical horizon
    3. C.The wing span and the fuselage longitudinal axis
    4. D.The runway surface and the aerofoil upper contour

    Explanation: The FAA states, "The AOA is defined as the acute angle between the chord line of the airfoil and the direction of the relative wind." Angle of attack is an airflow-relative angle; pitch attitude and planform geometry are different angles.

    Reference: FAA Pilot’s Handbook of Aeronautical Knowledge — Aerodynamics of Flight — Forces Acting on the Aircraft