Austro Control ATPL Principles of
Flight Practice Questions
Section 1: Basic Aerodynamics & Definitions (Questions 1–50)
Question 1: The angle between the aeroplane longitudinal axis and the chord line is the:
A) Angle of incidence
B) Glide path angle
C) Angle of attack
D) Climb path angle
Answer: A
*Rationale:* The angle of incidence is the fixed angle between the aeroplane's longitudinal axis
and the wing chord line, set by the manufacturer.
Question 2: The angle of attack of a wing profile is defined as the angle between:
A) The undisturbed airflow and the chordline
B) The local airflow and the mean camberline
C) The local airflow and the chordline
D) The undisturbed airflow and the mean camberline
Answer: A
*Rationale:* Angle of attack is the angle between the undisturbed relative airflow and the wing
chord line.
Question 3: The term angle of attack is defined as:
A) The angle that determines the magnitude of the lift force
B) The angle between the wing chord line and the relative wind
C) The angle between the relative airflow and the horizontal axis
D) The angle between the wing and tailplane incidence
Answer: B
*Rationale:* Angle of attack is the angle between the wing chord line and the relative wind.
Question 4: Wing loading is:
A) The ratio of lift to wing weight
B) The ratio of wing area to wing weight
,C) The ratio of lift to aircraft weight
D) The ratio of aircraft weight to wing area
Answer: D
*Rationale:* Wing loading is the ratio of aircraft weight to wing area.
Question 5: The unit of measurement of pressure is:
A) psi
B) kg/m³
C) lb/gal
D) kg/dm²
Answer: A
*Rationale:* Pressure is measured in psi (pounds per square inch).
Question 6: The unit of density is:
A) Bar
B) psi
C) kg/cm²
D) kg/m³
Answer: D
*Rationale:* Density is measured in kg/m³.
Question 7: The point about which the wing pitching moment is independent of angle of attack is
called:
A) The pitching centre
B) The centre of gravity
C) The centre of pressure
D) The aerodynamic centre
Answer: D
*Rationale:* The aerodynamic centre is the point about which the pitching moment is
independent of angle of attack.
Question 8: Considering a positive cambered aerofoil, the pitching moment when Cl=0 is:
A) Infinite
B) Positive (nose-up)
C) Negative (nose-down)
D) Equal to zero
Answer: C
*Rationale:* A positively cambered aerofoil produces a nose-down pitching moment when the lift
coefficient is zero.
,Question 9: The angle of attack of a two-dimensional wing section is the angle between:
A) The chord line of the aerofoil and the relative airflow
B) The mean camber line and the relative airflow
C) The chord line and the longitudinal axis
D) The mean camber line and the chord line
Answer: A
*Rationale:* The angle of attack of a two-dimensional wing section is the angle between the
chord line and the relative airflow.
Question 10: The relationship between lift coefficient and angle of attack for a two-dimensional
aerofoil is:
A) Linear up to the stall
B) Non-linear throughout
C) Constant
D) Exponential
Answer: A
*Rationale:* The lift coefficient increases linearly with angle of attack up to the critical angle,
after which it decreases.
Question 11: Which of the following is the correct formula for lift?
A) L = ½ ρ V² S CL
B) L = ρ V S CL
C) L = ½ ρ V S CL
D) L = ρ V² S CL
Answer: A
*Rationale:* The lift equation is L = ½ ρ V² S CL where ρ is air density, V is true airspeed, S is
wing area, and CL is the lift coefficient.
Question 12: What is the primary cause of lift generation on an aerofoil?
A) Equal transit time theory
B) Pressure difference between upper and lower surfaces
C) Angle of attack only
D) Airfoil thickness only
Answer: B
*Rationale:* Lift is produced due to pressure differences over and under the airfoil, with lower
pressure on the upper surface.
Question 13: According to Newtonian principles, lift is the reaction to:
A) Upward acceleration of air
, B) Downward acceleration of air
C) Forward acceleration of air
D) Backward acceleration of air
Answer: B
*Rationale:* Newton's third law states lift is the reaction to downward acceleration of air; equal
transit time is false.
Question 14: Which factor primarily generates lift?
A) Airflow over the wing creating pressure difference
B) Engine thrust
C) Aircraft weight
D) Wing fuel load
Answer: A
*Rationale:* Lift is produced due to pressure differences over and under the airfoil.
Question 15: What is angle of attack (AOA)?
A) Angle between chord line of wing and relative airflow
B) Angle between fuselage and horizon
C) Flap deflection angle
D) Rudder angle
Answer: A
*Rationale:* AOA directly affects lift and stall characteristics.
Question 16: The centre of pressure is the point:
A) Where the aerodynamic force acts
B) Where the weight acts
C) Where the thrust acts
D) Where the drag acts
Answer: A
*Rationale:* The centre of pressure is the point on the aerofoil where the total aerodynamic
force acts.
Question 17: The mean camber line is:
A) The line equidistant from the upper and lower surfaces
B) The straight line connecting leading and trailing edges
C) The line of maximum thickness
D) The line of maximum curvature
Answer: A
Flight Practice Questions
Section 1: Basic Aerodynamics & Definitions (Questions 1–50)
Question 1: The angle between the aeroplane longitudinal axis and the chord line is the:
A) Angle of incidence
B) Glide path angle
C) Angle of attack
D) Climb path angle
Answer: A
*Rationale:* The angle of incidence is the fixed angle between the aeroplane's longitudinal axis
and the wing chord line, set by the manufacturer.
Question 2: The angle of attack of a wing profile is defined as the angle between:
A) The undisturbed airflow and the chordline
B) The local airflow and the mean camberline
C) The local airflow and the chordline
D) The undisturbed airflow and the mean camberline
Answer: A
*Rationale:* Angle of attack is the angle between the undisturbed relative airflow and the wing
chord line.
Question 3: The term angle of attack is defined as:
A) The angle that determines the magnitude of the lift force
B) The angle between the wing chord line and the relative wind
C) The angle between the relative airflow and the horizontal axis
D) The angle between the wing and tailplane incidence
Answer: B
*Rationale:* Angle of attack is the angle between the wing chord line and the relative wind.
Question 4: Wing loading is:
A) The ratio of lift to wing weight
B) The ratio of wing area to wing weight
,C) The ratio of lift to aircraft weight
D) The ratio of aircraft weight to wing area
Answer: D
*Rationale:* Wing loading is the ratio of aircraft weight to wing area.
Question 5: The unit of measurement of pressure is:
A) psi
B) kg/m³
C) lb/gal
D) kg/dm²
Answer: A
*Rationale:* Pressure is measured in psi (pounds per square inch).
Question 6: The unit of density is:
A) Bar
B) psi
C) kg/cm²
D) kg/m³
Answer: D
*Rationale:* Density is measured in kg/m³.
Question 7: The point about which the wing pitching moment is independent of angle of attack is
called:
A) The pitching centre
B) The centre of gravity
C) The centre of pressure
D) The aerodynamic centre
Answer: D
*Rationale:* The aerodynamic centre is the point about which the pitching moment is
independent of angle of attack.
Question 8: Considering a positive cambered aerofoil, the pitching moment when Cl=0 is:
A) Infinite
B) Positive (nose-up)
C) Negative (nose-down)
D) Equal to zero
Answer: C
*Rationale:* A positively cambered aerofoil produces a nose-down pitching moment when the lift
coefficient is zero.
,Question 9: The angle of attack of a two-dimensional wing section is the angle between:
A) The chord line of the aerofoil and the relative airflow
B) The mean camber line and the relative airflow
C) The chord line and the longitudinal axis
D) The mean camber line and the chord line
Answer: A
*Rationale:* The angle of attack of a two-dimensional wing section is the angle between the
chord line and the relative airflow.
Question 10: The relationship between lift coefficient and angle of attack for a two-dimensional
aerofoil is:
A) Linear up to the stall
B) Non-linear throughout
C) Constant
D) Exponential
Answer: A
*Rationale:* The lift coefficient increases linearly with angle of attack up to the critical angle,
after which it decreases.
Question 11: Which of the following is the correct formula for lift?
A) L = ½ ρ V² S CL
B) L = ρ V S CL
C) L = ½ ρ V S CL
D) L = ρ V² S CL
Answer: A
*Rationale:* The lift equation is L = ½ ρ V² S CL where ρ is air density, V is true airspeed, S is
wing area, and CL is the lift coefficient.
Question 12: What is the primary cause of lift generation on an aerofoil?
A) Equal transit time theory
B) Pressure difference between upper and lower surfaces
C) Angle of attack only
D) Airfoil thickness only
Answer: B
*Rationale:* Lift is produced due to pressure differences over and under the airfoil, with lower
pressure on the upper surface.
Question 13: According to Newtonian principles, lift is the reaction to:
A) Upward acceleration of air
, B) Downward acceleration of air
C) Forward acceleration of air
D) Backward acceleration of air
Answer: B
*Rationale:* Newton's third law states lift is the reaction to downward acceleration of air; equal
transit time is false.
Question 14: Which factor primarily generates lift?
A) Airflow over the wing creating pressure difference
B) Engine thrust
C) Aircraft weight
D) Wing fuel load
Answer: A
*Rationale:* Lift is produced due to pressure differences over and under the airfoil.
Question 15: What is angle of attack (AOA)?
A) Angle between chord line of wing and relative airflow
B) Angle between fuselage and horizon
C) Flap deflection angle
D) Rudder angle
Answer: A
*Rationale:* AOA directly affects lift and stall characteristics.
Question 16: The centre of pressure is the point:
A) Where the aerodynamic force acts
B) Where the weight acts
C) Where the thrust acts
D) Where the drag acts
Answer: A
*Rationale:* The centre of pressure is the point on the aerofoil where the total aerodynamic
force acts.
Question 17: The mean camber line is:
A) The line equidistant from the upper and lower surfaces
B) The straight line connecting leading and trailing edges
C) The line of maximum thickness
D) The line of maximum curvature
Answer: A
