PPL training lessons

Question 1

Name all the aerodynamic forces acting on an aircraft

Answer 1

Thrust, drag
lift, weight

Question 2

What is lift

Answer 2

The upwards force acting on an aircraft, it is caused by relative wind and the wing design

Question 3

What is weight

Answer 3

The combined load of the aircraft itself, fuel, baggage cargo or anything onboard the aircraft. Weight opposes lift and acts vertically downwards through the aircraft’s center of gravity.

Question 4

When are weight and lift equal

Answer 4

In steady unaccelerated flight

Question 5

What is thrust

Answer 5

A forward moving force. In order for an aircraft to move forward, it must first overcome drag

Question 6

What are the two types of drag

Answer 6

Parasite drag
-form drag
(air going around the shape of the aircraft)
-interference drag
(when different streams of airflow interfere with each other creating little pockets of turbulence)
-skin friction drag
(Drag caused by the surface of the aircraft)

Induced drag
(drag that is created as a direct result of lift)

Question 7

What is the lift to drag ratio

Answer 7

The optimum speed where an aircraft can achieve the least possible amount of drag

Question 8

When are thrust and drag equal

Answer 8

In steady unaccelerated flight

Question 9

What is stall

Answer 9

A condition in which the lift suddenly decreases and the drag suddenly increases

Question 10

When will an aircraft not stall

Answer 10

As long as lift is more powerful than weight, the airplane will still fly

Question 11

How does the angle of attack affect stall

Answer 11

If we increase the angle of attack, there will come a time where the lift produced can no longer support the weight, there will be a stall.

If the angle of attack goes beyond the critical, it will stall

Question 12

Each airplane has a specific angle of attack at which it stalls at. What affects the speed at which the aircraft stalls at?

Answer 12

Altitude and gross weight affect the speed at which an aircraft stalls at, but the angle of attack will be the same

Question 13

what is the critical angle of attack

Answer 13

The optimum angle of attack before an airplane stalls at

Question 14

What is spin

Answer 14

An aggravated stall where yaw is introduced which causes a downwards corkscrew path

Question 15

What is spin (talk in terms of the wings)?

Answer 15

When an aircraft stalls, it is possible for one wing to stall more than the other, causing an aggravated stall leading to a spin

Question 16

What is uncoordinated flight (what is it also known as)

Answer 16

Any time the vertical axis of the aircraft is not aligned with the direction of travel. It is also known as a side slip

Question 17

What is stability

Answer 17

Stability is the ability of an aircraft to correct for disturbances in its equilibrium and return to its original flight path.

Question 18

Most aircraft’s are designed with what inn mind?

Answer 18

Stability

Question 19

The less stable an aircraft the more what is it?

Answer 19

More manauverable it is, like fighter jets

Question 20

What are the two types of stability

Answer 20

Static
-initial tendency of the aircraft after the equilibrium is disturbed
(what your airplane’s immediate reaction is after you make a control input)
There can be positive neutral and negative static stability

-dynamic
The airplanes response to an upset in the equilibrium over time
There is an positive negative and neutral dynamic stability

Question 21

What is positive static stability

Answer 21

If your airplane pitches up then goes back to its original.
So there’s a change in the equilibrium but that is fixed and it goes back to normal

Question 22

What is neutral static stability

Answer 22

If you pitch the airplane up and it continues at that exact angle.

Question 23

What is negative static stability

Answer 23

If you pitch the airplane up at an angle and it goes beyond that angle (it is undesirable)

Question 24

Explain neutral dynamic stability

Answer 24

If the oscillations stayed the same over time after a disturbance in the equilibrium

Question 25

Explain negative dynamic stability

Answer 25

If the oscillations get bigger over time

Question 26

What is controllability

Answer 26

How well the airplane responds to your control inputs

Question 27

If stability decreases, what happens to controlability

Answer 27

Controllability also decreases

Question 28

Give me 3 ways in which we affect controllability on an aircraft

Answer 28

By moving its centre of gravity
We can also change the AoA
Or by making power changes

Question 29

What causes the centre of lift to move back

Answer 29

When you increase the speed of your airplane and reduce the angle of attack, the centre of lift will move backwards.

Question 30

What can make an airplane become more stable

Answer 30

An increase in distance between your centre of gravity and your centre of lift

Question 31

What are three ways the plane moves (axis)

Answer 31

-lateral axis (longitudinal movements on pitch axis)
-longitudinal axis (roll axis)
-vertical axis (yaw axis)

Question 32

Describe the plane moving on its lateral axis

Answer 32

This is when the airplane pitches up and down and moves longitudinally

Question 33

Describe the plane moving on its longitudinal axis

Answer 33

In the longitudinal axis the plane moves laterally

Question 34

Describe the plane moving on its vertical axis

Answer 34

This is where we get our sideways movement

Question 35

How do we create movements on the lateral axis

Answer 35

Movements on the lateral axis are made by using the elevator.
We use the yoke to make this control input.

Question 36

Explain what makes the airplane turn?

Answer 36

We turn the airplane by banking it on the longitudinal axis.
We do this by rotating the yoke right or left.

When we rotate the yoke to the left it raises the left aileron and lowers the right aileron. The lowered aileron will create more lift and will cause that wing to rise thus will then cause the plane to rotate to the left.

Question 37

how do airplanes fly

Answer 37

The engine is responsible for creating a force called thrust, which will make the airplane move forward.
Thrust varies on the type of engine
As the airplane accelerates during takeoff air begins flowing over the wings due to the way that the wing is shaped.
The air flowing above the wing gets accelerated which then creates a low pressure area.
High level pressure wants to go to low pressure so the wing creates a force called lift which opposes gravity and causes the plane to fly

Question 38

Why do airplanes need flaps

Answer 38

They increase lift and drag because of this we can land at slower airspeeds which is safer and easier
When we don’t need them we can raise them and cruise at higher airspeeds