Airbus A320 CBT #008 Auto Flight System - System Presentation

Summary

The A320 family’s Autoflight System (AFS) is designed to assist pilots in flying the aircraft within the normal flight envelope, enhancing safety and performance. The system includes four main sections: a central processing unit, input devices, computation/processing units (FMGS), and output devices. The FMGS, consisting of two flight management guidance computers, receives navigation and performance data, providing outputs to flight directors, autopilots, and auto-thrust systems. The system manages functions like navigation, flight planning, performance optimization, flight guidance, and augmentation, ensuring precise control of the aircraft throughout its flight.

Takeaways

• 😀 The Autoflight System (AFS) on the A320 family assists pilots in flying within the normal flight envelope, improving safety and optimizing performance.
• 😀 The AFS consists of four main sections: central processing, input devices, computation and processing, and output devices.
• 😀 The heart of the AFS is the central processing section, which accesses various information sources and is connected to input and output devices.
• 😀 Two Flight Management Guidance Computers (FMGCs) handle the computation and processing tasks in the AFS, and they usually work in tandem.
• 😀 For training purposes, the two FMGCs are grouped as the Flight Management Guidance System (FMGS), which receives navigation, aircraft performance, and dynamic information.
• 😀 Pilots provide input to the FMGS via two Multi-Purpose Control and Display Units (MCDUs) for long-term adjustments and a single Flight Control Unit (FCU) for short-term inputs.
• 😀 The FMGS outputs commands to the Flight Directors (FDs), Auto Pilots (AP), Auto Thrust (A/THR), MCDUs, EFIS (Electronic Flight Instrument System), and navigation radios.
• 😀 The FMGS is divided into three main parts: Flight Management, Flight Guidance, and Flight Augmentation.
• 😀 The Flight Management section handles navigation, flight planning, performance optimization, and display management.
• 😀 The Flight Augmentation section includes functions such as envelope protection, wind shear warning, angle of attack protection, and maneuvering speed computation, ensuring safe operation within limits.

Q & A

What is the purpose of the AutoFlight System (AFS) on the Airbus A320 family?

The purpose of the AFS is to assist the pilot in flying the aircraft within the normal flight envelope, enhancing safety and optimizing performance.

How is the AutoFlight System (AFS) structured?

The AFS is structured into four main sections: the central processing section (FMGCs), input devices (MCDUs and FCU), output devices (autopilot, flight directors, autothrust), and the associated sensors and interfaces.

What are the primary components of the computation and processing section in the AFS?

The computation and processing section is primarily handled by two identical Flight Management Guidance Computers (FMGCs), which work together to process navigation, aircraft performance, and dynamic information.

How do pilots interact with the AFS?

Pilots interact with the AFS through the Multi-purpose Control and Display Units (MCDUs) for long-term interventions and the Flight Control Unit (FCU) for short-term interventions.

What are the main outputs of the FMGCs?

The FMGCs provide outputs to the flight directors (FDs), autopilots (APs), autothrust system, MCDUs, EFIS displays, and navigation radios for automatic tuning.

How are the FMGCs synchronized?

The FMGCs are synchronized by exchanging information for validity checks. For example, information from MCDU 1 is received by FMGC 1 and transmitted to FMGC 2, ensuring consistency across the system.

What is the role of the Flight Management part of the FMGS?

The Flight Management part controls functions such as navigation, flight planning, performance optimization, and display management, ensuring the aircraft follows the planned route efficiently.

What does the Flight Guidance part of the FMGS handle?

The Flight Guidance part provides commands to the autopilot for automatic control of pitch, roll, and yaw, as well as autothrust commands for thrust control. It also provides flight director commands for the pilot to control the aircraft manually.

What functions are managed by the Flight Augmentation part of the FMGS?

The Flight Augmentation part manages flight envelope computations, including minimum and maximum speed calculations, maneuvering speeds for different flap configurations, wind shear detection, and angle of attack protection (alpha floor).

What happens if one FMGC is declared as master?

When one FMGC is declared as master (e.g., if autopilot 1 is on), it determines which autothrust channel is operative and takes precedence in managing the system's outputs.