AFCS (MOD 3-5)

Question 1

is a set of devices that manages, commands, directs, or regulates the
behavior of other systems using control loops.

Answer 1

control system

Question 2

Types of Control Systems

Answer 2

• Open-loop system
• Closed-loop system

Question 3

• No feedback
• Output is not measured or corrected
• Example: Washing machine timer

Answer 3

Open-loop system

Question 4

This system act blindly they don’t check if the
result is correct.

Answer 4

Open-loop system

Question 5

• Output is constantly monitored
• Errors are corrected
• Example: Aircraft autopilot

Answer 5

Closed-loop system

Question 6

This system constantly check the output and make corrections, just like how an autopilot corrects the aircraft’s flight path.

Answer 6

Closed-loop system

Question 7

Components of a feedback control system

Answer 7

• Input
• Controller
• Actuator
• Sensor
• Feedback path

Question 8

This components of a feedback control system is the desired value (e.g., heading, altitude)

Answer 8

Input (Set point)

Question 9

This components of a feedback control system compares desired and actual output

Answer 9

Controller

Question 10

This components of a feedback control system executes correction (moves control surfaces)

Answer 10

Actuator

Question 11

This components of a feedback control system measures output (e.g., gyroscope, pressure sensor)

Answer 11

Sensor

Question 12

This components of a feedback control system sends actual output to the controller

Answer 12

Feedback path

Question 13

is a component that converts
electrical signals into mechanical
movement.

Answer 13

Actuator

Question 14

Types of actuator

Answer 14

• Hydraulic actuator
• Electric actuator
• Pneumatic actuator

Question 15

This type of actuator is used for high force (landing gear)

Answer 15

Hydraulic actuator

Question 16

This type of actuator is lightweight, for precise control (flaps)

Answer 16

Electric actuator

Question 17

This type of actuator uses air pressure

Answer 17

Pneumatic actuator

Question 18

is a small device that receives a control signal and adjusts its output precisely in response.

Answer 18

Servo

Question 19

Components of a servo

Answer 19

• DC motor/AC motor
• Gearbox
• Control Circuit/Servo Controller
• Feedback device (e.g., potentiometer or encoder)
• Output shaft/arm

Question 20

This servo component provides the motion or torque

Answer 20

DC motor/AC motor

Question 21

This servo component:
- reduces speed and increases torque.
- Allows precise control of movement

Answer 21

Gearbox

Question 22

This servo component:
- Receives the command signal.
- Interprets and sends the right power to the motor.

Answer 22

• Control Circuit/Servo Controller

Question 23

This servo component:
- Monitors the output shaft position.
- Sends data back to the controller for comparison.

Answer 23

Feedback device

Question 24

This servo component:
- The part that moves and performs the
action.
- Connects to control surfaces,
actuators, etc.

Answer 24

Output shaft/arm

Question 25

- Control systems regulate machines ___ - Feedback (___) ensures accuracy - Servos provide ___ motion control - ___ perform mechanical work

Answer 25

- Automatically - closed-loop - precise - Actuators

Question 26

Flight control systems are subject to strict

Answer 26

FAA safety regulations

Question 27

Identify the Code of Federal Regulation being described and fill in the blanks (if applicable): - Requires systems (e.g., Fly-by-Wire) to remain safe after failures. - If automation is essential to control: it must be ___, include ___, permit ___ - Even if a control computer fails, the aircraft must remain flyable. - Airbus's control law transitions (___ → ___ → ___) reflect compliance with this rule.

Answer 27

14 CFR S 25.672 - Stability Augmentation and Automation - extremely reliable - fail-safe features - pilot override - Normal → Alternate → Direct

Question 28

Identify the Code of Federal Regulation being described and fill in the blanks (if applicable): - Systems must: - Work under all conditions - Undergo safety assessment - Not allow single-point catastrophic failure

Answer 28

14 CFR S 25.1309 - Equipment, Systems, and Installations

Question 29

Identify the Code of Federal Regulation being described and fill in the blanks (if applicable): - Aircraft must be controllable: - In all phases of flight - With reasonable pilot effort - In any loading or configuration state

Answer 29

14 CFR S 25.143 - Controllability

Question 30

Identify the Code of Federal Regulation being described and fill in the blanks (if applicable): - Describes how flight computers use ____ - Laws may adjust based on flight phase, failure, or mode - May include protections for stall, overspeed, etc.

Answer 30

FAA AC 25-11B – Electronic Flight Control Systems - control laws

Question 31

A ___ is a programmed logic in a ___ system that determines how pilot inputs are interpreted by the ___.

Answer 31

- control law - Fly-by-Wire (FBW) - flight control computer

Question 32

Control law controls how the aircraft responds based on:

Answer 32

- Flight phase - Aircraft condition - System health

Question 33

Types of control laws

Answer 33

- Normal law - Alternate law - Direct law

Question 34

This control law provides full protection: stall, overspeed, bank/pitch limits - Limits: Pitch, roll, stall, overspeed, bank angle - Prevents dangerous movements - Example: Can’t exceed bank angle of 67°

Answer 34

Normal law

Question 35

This control law reduced protection during certain failures - Triggered when a system fault occurs - Still offers some help (e.g., stall protection might remain)

Answer 35

Alternate law

Question 36

This control law provides no protection; pilot has full manual input authority - Pilot has full manual control - Used only in serious failures or emergencies

Answer 36

Direct law

Question 37

Identify the Code of Federal Regulation being described and fill in the blanks (if applicable): - Design must consider: - Failure modes and effects (FMEA) - Redundancy (e.g., dual/triple-redundant actuators) - Crew workload (minimize overcontrol) - Feedback and stability augmentation - ___ systems must be intuitive and responsive

Answer 37

FAA AC 25-7D, Flight Test Guide for Certification of Transport Category Airplanes - Pilot-In-the-Loop

Question 38

This is the phase of flight between the climb and descent.

Answer 38

CRUISING FLIGHT

Question 39

The aircraft maintains a steady altitude and speed, typically at a higher altitude to optimize ___

Answer 39

fuel efficiency

Question 40

Standard cruising altitude for general aviation.

Answer 40

Below FL290 (29,000 feet)

Question 41

In this altitude aircraft may transition to more sophisticated altitude management, including RVSM (Reduced Vertical Separation Minima) where altitudes are often assigned in 1000-foot increments.

Answer 41

Above FL290

Question 42

Requirements for Safe Cruising Flight:

Answer 42

- Aircraft performance - Fuel consideration - Weather condition

Question 43

The ___ can be used to control altitude, heading, and speed during cruise.

Answer 43

G1000 autopilot

Question 44

G1000 autopilot features

Answer 44

- Altitude hold - Vertical speed mode - Heading hold - Navigation mode

Question 45

It shows guidance for level flight, and the autopilot can follow these commands

Answer 45

Flight director

Question 46

The G1000 system uses ___, ___, and ___ inputs for navigation.

Answer 46

- GPS - VOR - ILS

Question 47

In cruise, the aircraft is typically following a ___. The G1000 will show active waypoints and future route segments on the ___.

Answer 47

- GPS flight plan - MFD

Question 48

are modular units that can be replaced or serviced without removing the entire avionics system

Answer 48

Line Replaceable Units (LRUs)

Question 49

Identify the LRU: - Responsible for GPS navigation, radio navigation (VOR, ILS), and communication functions. - ensures that the aircraft follows the correct flight path.

Answer 49

GIA

Question 50

Identify the LRU: - These units manage the PFD and MFD. - These provide pilots with critical flight data and navigation information during cruise.

Answer 50

GDU

Question 51

Identify the LRU: - This LRU processes information from the pitot-static system, providing airspeed, altitude, and vertical speed data. - Ensures that the PFD is showing accurate flight data for safe cruising.

Answer 51

GDC

Question 52

Identify the LRU: - Ensures accurate heading information is available, even during potential GPS failures.

Answer 52

GMU

Question 53

Identify the LRU: - Provides attitude, heading, and other critical flight information used to maintain level flight during cruise.

Answer 53

GRS