Part 2: Principles of Flight

Question 1

What is Newton’s 3rd Law?

Answer 1

To every action, there is an equal and opposite reaction.

Question 2

What is Bernouili’s Principle?

Answer 2

As airspeed increases, air pressure decreases

Question 3

in straight and level flight at constant speed, which forces are in balance?

Answer 3

Weight = Lift; Thrust = Drag

Question 4

What is the angle of attack of a wing?

Answer 4

The angle between the chord line of the wing and the oncoming air

Question 5

Where does air flow faster around a wing?

Answer 5

Over the top

Question 6

How much lift is generated by the top of the wing?

Answer 6

Up to 80%

Question 7

Where is the greatest effect of lift on the wing?

Answer 7

Nearer the front edge of the wing

Question 8

What is the relationship between air flow and lift?

Answer 8

Lift is at 90 degrees to air flow

Question 9

How does drag vary in relation to airspeed?

Answer 9

The square of airspeed: 2 x airspeed = 4 x drag

Question 10

What are the three planes of movement?

Answer 10

lateral, longitudinal, normal

Question 11

What controls a plane’s pitch?

Answer 11

Elevators

Question 12

What controls a plane’s roll?

Answer 12

Ailerons

Question 13

What controls a plane’s yaw?

Answer 13

Rudder

Question 14

What are dihedral wings?

Answer 14

Wings angled upwards (to create lateral stability)

Question 15

What are anhedral wings?

Answer 15

Wings angled downwards

Question 16

What do trimming tabs do?

Answer 16

Cancel out forces on flight controls

Question 17

What do flaps do?

Answer 17

They adjust lift and drag created by a wing (by changing its shape)

Question 18

What degree of flap give the best increase in lift?

Answer 18

30-60 degrees

Question 19

What degree of flap gives maximum drag?

Answer 19

90 degrees

Question 20

What are slats?

Answer 20

At front of wing, reduce stalling speed

Question 21

What is the critical angle of attack?

Answer 21

15 degrees (after this stalling is likely)

Question 22

What forces act on a glider?

Answer 22

Weight, drag and lift

Question 23

How does a glider speed up?

Answer 23

Lowers the nose

Question 24

How does a glider slow down?

Answer 24

Using airbrake

Suggested better answer by Katie Nixon:

A glider slows down by pitching nose up (using airbrakes only increases the rate of descent)

Question 25

What control makes a helicopter produce lift?

Answer 25

Collective pitch control

Question 26

What control makes a helicopter move forwards/backwards and side to side?

Answer 26

Cyclic pitch control

Question 27

What undesirable effect is generated by helicopter rotor blades?

Answer 27

Torque reaction

Question 28

What counters the torque reaction in helicopters?

Answer 28

Rudder pedals

Question 29

What control makes a helicopter rotate?

Answer 29

Rudder pedals

Question 30

What is angle A?

Answer 30

The angle of attack

Question 31

Where is air pressure lowest?

Answer 31

At point B (where airflow is the fastest)

Question 32

What is this aircraft doing?

Answer 32

Pitching

Question 33

What is this aircraft doing?

Answer 33

Rolling

Question 34

What is this aircraft doing?

Answer 34

Yawing

Question 35

What is happening in the bottom diagram?

Answer 35

The plane is stalling (note angle of attack is 16 degrees, one degree more than the “critical” angle of attack).

Question 36

This diagram shows a plane pitching, rolling and yawing + their controls.

These are done across which three axis?

Answer 36

Pitching across the lateral axis.

Rolling across the longitudinal axis.

Yawing across the normal (or vertical) axis.

Question 37

The diagram shows the three axes. What is movement across each of these called?

Answer 37

Movement across longitudinal axis = rolling.

Movement across lateral axis = pitching.

Movement across normal axis = yawing.