Unit 1

Question 1

Airfoil

Answer 1

Any surface designed to obtain a desired reaction force when in motion relative to the surrounding air.

Question 2

Camber

Answer 2

The curvature of the airfoil from the leading edge to the trailing edge.

Question 3

Chord line

Answer 3

An imaginary straight line drawn from the leading edge to the trailing edge of a cross section of an airfoil.

Question 4

Leading edge

Answer 4

The edge of the airfoil that faces forward in flight and is normally rounded.

Question 5

Trailing Edge

Answer 5

The back edge of the airfoil that passes through the air last and is normally narrow and tapered.

Question 6

Angle of attack

Answer 6

The angle between the chord line of the wing and the relative wind which is parallel to the flight path.

Question 7

Angle of incidence

Answer 7

The angle formed by the chord line of the wing and longitudinal axis of the airplane.

Question 8

Attitude

Answer 8

The relationship of the airplane to the horizon (pitch) and its bank angle.

Question 9

Center of gravity

Answer 9

The point about which an airplane would balance if it were possible to suspend it at that point.

Question 10

Center of pressure

center of lift

Answer 10

The point along the chord line of a wing at which all the aerodynamic forces (including lift) are considered to be concentrated.

Question 11

Dihedral

Answer 11

The angle at which the wings are slanted upward from the wing root to the wingtip.

Question 12

Relative wind

Answer 12

The direction of the airflow produced by an object moving through the air.

Question 13

Stall

Answer 13

The loss of lift and increase in drag that occurs when an aircraft is flown at an angle of attack greater than the angle for maximum lift. (The critical angle of attack)

Question 14

Sweepback

Answer 14

The angle at which the wings are slanted rearward from the wing root to the wingtip.

Question 15

Washout

Answer 15

Design of a wing in which it is twisted such that the angle of incident is less at the wingtip then at the wing root.

Question 16

Wing area

Answer 16

The entire surface of the wing (expressed in square feet), including control surfaces.

Question 17

Wing planform

Answer 17

The shape or form of a wing as viewed the above.

Question 18

Wingspan

Answer 18

The maximum distance from wingtip to wingtip.

Question 19

Speed

Answer 19

The distance traveled in a given time.

Question 20

Vector

Answer 20

The graphic representation of a force.

Question 21

Velocity

Answer 21

The speed or rate of movement in a certain direction.

Question 22

Acceleration

Answer 22

A change of velocity per unit of time.

Question 23

Fuselage

Answer 23

Is the main component of the airplane.

Question 24

Truss type

Answer 24

A type of fuselage which is a reinforced shell where the skin is supported by a complex framework of structural members that bear the main stress loads.

Question 25

Monocoque type

Answer 25

A fuselage type which has little or no internal bracing other than bulkheads where the outer skin bears the main stress loads.

Question 26

Semi-Monocoque

Answer 26

A fuselage type where the skin is reinforced by longerons or bulkheads the share the main stress loads.

Question 27

Wings

Answer 27

Are airfoils attached to each side of fuselage and are the main lifting surfaces supporting the airplane in flight.

Question 28

What are the two types of wings?

Answer 28

Cantilever wing

Semi-cantilever wing

Question 29

What is the difference between the cantilever and semi-cantilever wing?

Answer 29

The semi-cantilever wing is attached to the fuselage by both external braces and internal spars and ribs. The cantilever wing requires no external bracing. The stress is carried by internal wings spars, ribs, and stringers.

Question 30

What are the two movable surfaces of a wing?

Answer 30

Ailerons

Wing flaps

Question 31

Describe the ailerons of a wing

Answer 31

They are the movable surface located outboard on the wings and move in opposite directions.

Question 32

What is the purpose of the ailerons?

Answer 32

The imbalance of lift caused by the movement of the aileron causes the airplane to bank.

Question 33

Describe the flaps of a wing

Answer 33

Flaps are located inboard on the wing and move together.

Question 34

Empennage

Answer 34

The tail section of an aircraft.

Question 35

Name the fixed and movable surfaces of the empennage.

Answer 35

Fixed surfaces: vertical stabilizer and horizontal stabilizer.

Movable surfaces: the rudder and elevator.

Question 36

What does the vertical stabilizer do?

Answer 36

It provides directional stability.

Question 37

What does the horizontal stabilizer do?

Answer 37

It provides longitudinal (pitch) stability.

Question 38

Powerplant

Answer 38

Usually includes both the engine and the propeller to provide the thrust to move the airplane.

Normally covered by a cowling or enclosed in a nacelle for protection and streamlining.

Question 39

What are the three axes of rotation?

Answer 39

Lateral axis
Longitudinal axis
Vertical axis

Question 40

Name the three important functions of a wing flaps

Answer 40

First, they permit a slower landing speed, which decreases the required landing distance.

Second, they permit a comparatively steep angle of descent without increase in speed, which makes it possible to clear obstacles safely when making a landing approach to a short runway.

Third, they may also be used to shorten the takeoff distance and provide a steeper climb path.