Auto-flight Systems and Backup Navigation

Auto-flight (ATA-22)

• Flight Management (FM) controls navigation radio management, performance prediction, flight planning, and display management
• Flight Guidance (FG) controls autopilot (AP), flight director (FD), and auto thrust (A/THR) commands
• Flight Envelope (FE) manages flight envelope and speed calculations, monitoring of parameters by FG/FE, and wind shear/CG detection

Backup NAV

• Provides functions for flight planning, aircraft position using onside IRS, IRS 3, or GPIRS, F-PLN on ND display, no AP/FD NAV mode, limited lateral revision, and F-PLN automatic sequencing
• Maximum of 150 waypoints
• Available backup NAV pages in MCDU (ref. A330: DSC 22_20 > 50-Controls and Indications > 10-MCDU – Page Description > FMS2 Thales > Back up NAV Pages/A332: replace FMS2 Thales with FMS2 Honeywell)

Ground Speed Mini

• Takes advantage of the aircraft's inertia during wind changes
• Ensures ground speed is at or above GROUND SPEED MINI during approach
• A/THR in speed mode automatically follows the speed target, efficiently managing thrust
• Minimum energy level at touchdown (represented by GROUND SPD MINI)
• Lowest speed target is VAPP, highest is VFE of the relevant configuration (CONF 1, 2, 3 or CONF FULL)

Alpha Floor

• A floor protection is triggered when the aircraft's angle of attack (AOA) is above a pre-determined threshold
• A/THR is automatically activated and TOGA thrust is selected
• Inhibited in case of engine failure (with flaps extended or de-rated TO selected), below 100ft at landing, and if Auto Thrust has failed

LOC Convergence Function

• Aims to help the aircraft intercept and capture the LOC axis, with a converging track of 20 NM from the LOC axis, when NAV mode is engaged, LOC mode is armed and the aircraft is within 20 NM of the destination runway, with the difference between the aircraft track and QFU being less than 20°
• Enhanced LOC Capture function improves LOC capture, helping to avoid overshoot

Land Mode

• ENGAGEMENT CONDITIONS: LAND mode automatically engages when LOC and G/S modes are engaged and the aircraft is below 400 ft RA
• DISENGAGEMENT CONDITIONS: LAND mode disengages upon go-around or when the flight crew engages the APPR pb. The LAND mode disables if the aircraft is on the ground for over 10 seconds.

Electrics (ATA-24)

• Two 3-phase AC generators driven by an IDG (115 KVA, 115/200V & 400 Hertz) providing enough power for the whole network
• One generator covers the entire network
• Each AC BUS is supplied in priority order by: Engine Generator, APU Generator, or External A/B (with External B having higher priority over External A)
• Emergency Generator (8 KVA of three-phase 115/200V 400 Hz power) to supply the AC electrical systems if all main generators fail. But, 3.5 KVA of emergency power is used if the RAT drives the Green circuit and the aircraft speed is below 260kt.

Land Recovery

• When pressed, AC LAND RECOVERY and DC LAND RECOVERY buses recover, with all related equipments recovering (LGCIU 1, SFCC 1, BSCU channel 1, LH windshield anti-ice, LH landing light)
• 260kt is the max speed for aircraft to work with the emergency generator.
• Fuel pump also shuts down.

Flight Control

• 3 PRIM Computers that handle normal, alternate, and direct law operations, speed brake or ground spoiler control, and protection speed computation
• 2 SEC Computers that handle direct law operations (including Yaw damper function),rudder trim, travel,and peddle limiter, allowing for control of the aircraft with total electrical failure of PRIMs (or a single PRIM failure)

Alpha Floor Protection

• MLA(Maneuver Load Alleviation) protects the wings from bending moments during high load factors. Uses spoilers 4,5,6 and ailerons for protection at speeds of greater than 250kt.

Fuel System (ATA-28)

• The wings have inner and outer tanks, each inner tank containing a fuel collector cell to maintain a fuel reservoir for the booster pumps. It will protect from negative G-force.
• Each collector cell has two main pumps, and a standby pump located outside each cell
• Fuel can expand by 2% with a 20°C increase in temperature
• Two FCMC computers that calculate Aircraft GW and CG using the ZFW and CG provided by the crew
• A X-Feed valve is associated with each engine to allow any pump to supply any engine.

Forward Fuel Transfer

• Transfers fuel from the center tank to the inner tanks
• Trim tanks transfer to the inner tanks.
• Outer tanks transfer to the inner tanks when the level drops
• Fuel transfers for 33 mins for A332, and 25 mins for A333, with dual coupling for A333 being faster
• Fuel in the tank can expands by 2%. 5000 kg of minimum fuel is required for takeoff
• Temperature of the fuel should be within -47°C to +55°C.

Engines

• Low-pressure, intermediate pressure, and high-pressure components (involves multiple compressors and turbines stages, fuel nozzles and igniters).
• Engine operation, (and start-up) sequences.

Hydraulics

• Three hydraulic systems (Green: ENG 1, ENG 2, Electric pump, and RAT; Blue: ENG 1 and Electric; Yellow: ENG 2 and Electric/hand pump)
• Operation when one or more engines fail, the RAT automatically activates to generate power, and the operation logic. In flight.
• The electric pump runs for 25 seconds after the flap selector switches to the up position when an engagement. Ensures timely gear retraction
• Operation and interactions of components (pumps, accumulators, bleeds)

Landing Gear

• Each main gear has a four wheel, twin tandem bogie assembly with an oleo pneumatic shock absorber.
• Hydraulic system is automatically isolated by closing a safety valve above 280kt. This valve remains closed until the landing gear is selected, and the speed is below 280kt.
• LGCIUs receive landing gear position and status data and transmits the data to other aircraft systems
• Nose Wheel Steering uses two actuators powered by the Green Hydraulic system.
• Brakes use carbon multidisc brakes, with normal systems using Green Hydraulic system and alternate system using Blue HYD (backed up by the hydraulic accumulator).

Antiskid System

• Deactivates below 10kt (Ground Speed)
• Compares the speed of each main gear wheel to the reference speed.
• Brake release orders are given if the speed of the wheel is below 0.88 times reference speed.
• Reference speed is calculated by BSCU with information from ADIRU1,2,or 3
• The system activates on command of the Ground Spoiler extension
• A system to protect the wheels are from locking up

Navigation

• Describes the different sensors measuring attitude and status, including pitot tubes, static pressure probes, angle-of-attack sensors, total air temperature probes, and 8 air-data modules
• Details of GPS system and how the data from multiple GPS satellites is used for navigation.
• Explains predictive WindShear system, and how the system operates.

GPWS (Ground Proximity Warning System)

• Explanation of how GPWS alerts are generated
• Describes different modes (e.g., Mode 1 to 5), including specific warnings for terrain closure, too low terrain, and descending below the glide slope. Explains how the GPWS interacts with other systems.

TCAS (Traffic Collision Avoidance System)

• Explains how TCAS alerts operate.
• Descriptions of different modes based on proximity to other aircraft, and different types of alerts.

APU (Auxiliary Power Unit)

• Powering and operation of the APU, with the system's maximum and minimum operating limits during different configurations, and start and stop sequences given.

Weights

• Lists various weight components of the aircraft, including taxi fuel, reserve fuel, and passenger/cargo load
• Provides figures for taxi weight, takeoff weight operational empty weight ,zero fuel weight, and weights for various other parts of the aircraft.

Other

• Tail strike tolerance, Altimeter toleranced, and RVSM conditions
• BUSS system operation