Flight Control (redone)

Question 1

Mechanical flight control system

Answer 1

Sport & small general aviation aircraft

Question 2

Modern aircraft are controlled via

Answer 2

Electrical interface:

• Electric Motors
• Digital Computers
• Fiber Optic Cables (Fly-by-Wire systems)

Question 3

Name the two types of flight control systems

Answer 3

Primary: Ailerons, Elevator, Rudder
Secondary: Wing Flaps, spoilers, trim systems

Question 4

What does the Primary control system control?

Answer 4

Airflow around the airfoil thus moving the aircraft around its 3 axis of rotation

Question 5

Ailerons control what axis

Answer 5

Longitudinal axis (roll)

Question 6

What is adverse yaw

Answer 6

When the plane rolls to the left or right

Question 7

To roll right, which aileron will do what?

Answer 7

Right aileron moves up, left aileron moves down

Question 8

What does adverse yaw cause during a left roll?

Answer 8

Left aileron moves up, right aileron moves down producing drag causing the plane to yaw right.

Question 9

What is adverse yaw and how do you counteract it?

Answer 9

When the plane yaws towards the outside of a bank (towards the lowered aileron). Use rudder pressure.

Question 10

When is the effect of adverse yaw magnified?

Answer 10

At slower speeds because of the decreased effectiveness of the vertical stabilizer & rudder.

Question 11

What 4 systems are used to counteract adverse yaw?

Answer 11

1. Coupled ailerons and rudder
2. Differential ailerons (aileron that deflects downward doesn’t deflect as much as the aileron that deflects up) to balance drag
3. Frise Type Ailerons - they move on an offset pivot and have slots
4. Flaperons - combine aspects of ailerons & flaps

Question 12

What does the elevator control?

Answer 12

Pitch about the lateral axis

Question 13

This is a characteristic of a T-tail plane

Answer 13

Remove horizontal stabilizer from exhaust blast and prop wash. Pilot must make larger movements at slow speeds to control pitch of nose.

Question 14

What is a stabilator?

Answer 14

Entire horizontal stabilator moves up and down.

Question 15

Describe a Canard design airplane?

Answer 15

Horizontal stabilizer is on the front of the plane before the main wings. Results in less drag for lift

Question 16

What axis does a rudder control?

Answer 16

Vertical axis (yaw)

Question 17

Left pedal will cause rudder to deflect in which direction?

Answer 17

Left

Question 18

What are ruddervators?

Answer 18

Combination rudder and elevator. They work much like flaperons

Question 19

Name secondary flight controls

Answer 19

1. Wing flaps
2. Leading Edge Devices
3. Spoilers
4. Trim Systems

Question 20

Flaps are the most common what

Answer 20

High lift devices

Question 21

Flaps increase what

Answer 21

lift and drag

Question 22

Name 4 types of flaps

Answer 22

Plain, split, slotted, fowler flap

Question 23

Describe plain flap

Answer 23

Most simple design. Increases camber of wing to increase lift and drag.

Question 24

Describe split flap

Answer 24

Deploy from lower surface of wing and increase lift more than plain flap. Both the plain and split flap design cause high drag for little lift

Question 25

Describe slotted flap

Answer 25

Most popular flap. Allows high energy air to flow from bottom of wing to top of the wing. Causes much greater lift force than plain or split flap.

Question 26

Describe Fowler flap

Answer 26

Change camber and increase wings surface area by sliding back and down rather than just down.

Question 27

4 most common types of leading edge devices

Answer 27

Fixed slot, movable slot leading edge flap, leading edge cuff

Question 28

Describe fixed slot

Answer 28

Leading edge device. Delay airflow separation until a higher angle of attack. Does not increase wings camber but still increases lift.

Question 29

Describe movable slot

Answer 29

Leading edge device. They open when angle of attack is increased or by the pilot. Work the same way as fixed slot

Question 30

Describe leading edge flap

Answer 30

Leading edge device. Work to increase the camber of the wing and are used with trailing edge flaps to reduce the nose down pitching tendency

Question 31

Describe leading edge cuffs

Answer 31

Leading edge device. Works to increase wing’s camber and lift. Front edge of wing is pushed down and forward allowing for more air to connect to the upper surface of the wing at higher AOA thus reducing the stall speed.

Question 32

Describe spoilers

Answer 32

Help by reducing lift and increasing drag over the wings surface. Used in gliders to control decent & in large aircraft to control adverse yaw. When used together they slow down plane and reduce ground roll by transferring weight to wheels thus increasing breaking efficiency

Question 33

What are trim systems used for?

Answer 33

Used to relieve the pilot of need to maintain constant pressure on the primary flight control surfaces

Question 34

What type of trim systems exist

Answer 34

Elevator, rudder, aileron trim systems

Question 35

What is configured before adjusting trim

Answer 35

1. Establish desired power setting
2. Establish desired pitch attitude
3. Establish desired configuration

Question 36

What is a balance tab?

Answer 36

Trim system that automatically moves opposite of control input to automatically relieve some pressure required to be held by the pilot

Question 37

What is an antiservo tab?

Answer 37

Work like balance tab by opposing force of pilot and making stabilizer less sensitive.

Question 38

Ground adjustable tab

Answer 38

Adjusted from ground to prevent skidding L or R during cruising flight

Question 39

What can autopilot work with?

Answer 39

1. Inertial navigation systems
2. Global positioning systems
3. Flight computers