Private Pilot Oral Exam Guide CHAPTER Save
4
Terms in this set (166)
Lift—the upward acting force
1. What are the four dynamic
Gravity—or weight, the downward acting force
forces that act on an airplane
Thrust—the forward acting force
during all maneuvers?
Drag—the backward acting force
In steady-state, straight-and-level, unaccelerated flight, the sum of
the opposing forces is equal to zero. There can be no unbalanced
2. What flight condition will result
forces in steady, straight flight (Newton's Third Law). This is true
in the sum of the opposing forces
whether flying level or when climbing or descending. It does not
being equal?
mean the four forces are equal. It means the opposing forces are
equal to, and thereby cancel the effects of each other.
An airfoil is a device which gets a useful reaction from air moving
What is an airfoil? State some
over its surface, namely LIFT. Wings, horizontal tail surfaces,
examples.
vertical tail surfaces, and propellers are examples of airfoils.
, Imagine the airplane's body (the fuselage) is a straight line, and the
wing's chord line (an imaginary line from the wing's front to back) is
tilted slightly upward when attached.
That tilt is the angle of incidence.
1. It's built into the airplane at the factory.
2. The pilot can't change it in flight.
3. It helps the airplane generate lift even when flying level.
What is the "angle of incidence"? 💡 Simple definition for Quizlet:
Angle of Incidence — The fixed angle between the airplane's body
and the wing's chord line; it's how the wing is attached to the
fuselage.
The angle of incidence is the angle formed by the longitudinal axis
of the airplane and the chord of the wing. It is measured by the
angle at which the wing is attached to the fuselage. The angle of
incidence is fixed and cannot be changed by the pilot
1. Relative wind = the airflow that hits the wing as the airplane
moves through the air.
2. It always moves in the exact opposite direction of the airplane's
flight path.
So if your airplane (and wing) are moving forward and
What is a "relative wind"? downward,➡️ the relative wind is moving backward and upward.
Think of it like this:
If you stick your hand out of a moving car window—your hand is
going forward
but the air hits it from the opposite direction — that's the relative
wind.
The angle of attack is the angle between the wing chord line and
What is the "angle of attack"?
the direction of the relative wind; it can be changed by the pilot.
, Bernoulli's Principle says that as the speed of airflow increases, its
pressure decreases. The wing's shape makes air move faster over
the top, creating low pressure above and higher pressure below.
The pressure difference produces lift, and together with the
downward deflection of air (Newton's 3rd Law), it keeps the
airplane flying.
The air that goes over the top has to move faster to meet up with
the air going underneath (because it's traveling a longer, curved
What is "Bernoulli's Principle"?
path).
When that air speeds up, its pressure drops (that's Bernoulli's
Principle).
The air moving underneath is slower, so it has higher pressure.
Now you have low pressure above and high pressure below → the
wing gets pushed upward = LIFT.
So, Bernoulli explains the pressure difference, and Newton
explains the reaction force.
Wing Area — Bigger wings make more lift and more drag. Some
flaps (like Fowler flaps) make the wing area bigger when extended.
Shape of the Airfoil — More curve (camber) on top = more lift (up
to a point). Flaps or ailerons can change the shape. Ice or frost
messes it up and kills lift.
What are several factors which
will affect both lift and drag? Angle of Attack — Tilting the wing up into the airflow increases lift
and drag — but only until it stalls.
Air Velocity — Faster air over the wing = more lift and drag.
Air Density — Thicker air (high pressure, low temp, dry) = more lift.
Thin air (high altitude, hot, humid) = less lift.
4
Terms in this set (166)
Lift—the upward acting force
1. What are the four dynamic
Gravity—or weight, the downward acting force
forces that act on an airplane
Thrust—the forward acting force
during all maneuvers?
Drag—the backward acting force
In steady-state, straight-and-level, unaccelerated flight, the sum of
the opposing forces is equal to zero. There can be no unbalanced
2. What flight condition will result
forces in steady, straight flight (Newton's Third Law). This is true
in the sum of the opposing forces
whether flying level or when climbing or descending. It does not
being equal?
mean the four forces are equal. It means the opposing forces are
equal to, and thereby cancel the effects of each other.
An airfoil is a device which gets a useful reaction from air moving
What is an airfoil? State some
over its surface, namely LIFT. Wings, horizontal tail surfaces,
examples.
vertical tail surfaces, and propellers are examples of airfoils.
, Imagine the airplane's body (the fuselage) is a straight line, and the
wing's chord line (an imaginary line from the wing's front to back) is
tilted slightly upward when attached.
That tilt is the angle of incidence.
1. It's built into the airplane at the factory.
2. The pilot can't change it in flight.
3. It helps the airplane generate lift even when flying level.
What is the "angle of incidence"? 💡 Simple definition for Quizlet:
Angle of Incidence — The fixed angle between the airplane's body
and the wing's chord line; it's how the wing is attached to the
fuselage.
The angle of incidence is the angle formed by the longitudinal axis
of the airplane and the chord of the wing. It is measured by the
angle at which the wing is attached to the fuselage. The angle of
incidence is fixed and cannot be changed by the pilot
1. Relative wind = the airflow that hits the wing as the airplane
moves through the air.
2. It always moves in the exact opposite direction of the airplane's
flight path.
So if your airplane (and wing) are moving forward and
What is a "relative wind"? downward,➡️ the relative wind is moving backward and upward.
Think of it like this:
If you stick your hand out of a moving car window—your hand is
going forward
but the air hits it from the opposite direction — that's the relative
wind.
The angle of attack is the angle between the wing chord line and
What is the "angle of attack"?
the direction of the relative wind; it can be changed by the pilot.
, Bernoulli's Principle says that as the speed of airflow increases, its
pressure decreases. The wing's shape makes air move faster over
the top, creating low pressure above and higher pressure below.
The pressure difference produces lift, and together with the
downward deflection of air (Newton's 3rd Law), it keeps the
airplane flying.
The air that goes over the top has to move faster to meet up with
the air going underneath (because it's traveling a longer, curved
What is "Bernoulli's Principle"?
path).
When that air speeds up, its pressure drops (that's Bernoulli's
Principle).
The air moving underneath is slower, so it has higher pressure.
Now you have low pressure above and high pressure below → the
wing gets pushed upward = LIFT.
So, Bernoulli explains the pressure difference, and Newton
explains the reaction force.
Wing Area — Bigger wings make more lift and more drag. Some
flaps (like Fowler flaps) make the wing area bigger when extended.
Shape of the Airfoil — More curve (camber) on top = more lift (up
to a point). Flaps or ailerons can change the shape. Ice or frost
messes it up and kills lift.
What are several factors which
will affect both lift and drag? Angle of Attack — Tilting the wing up into the airflow increases lift
and drag — but only until it stalls.
Air Velocity — Faster air over the wing = more lift and drag.
Air Density — Thicker air (high pressure, low temp, dry) = more lift.
Thin air (high altitude, hot, humid) = less lift.
