Autoflight Flashcards
When is WINDSHEAR protection provided?
Provided by the FACs in takeoff and approach phase
‐ At takeoff, 3 s after liftoff, up to 1 300 ft RA
‐ At landing, from 1 300 ft RA to 50 ft RA
‐ With at least CONF 1 selected
What are the components of the Flight Management Guidance System (FMGS)?
‐ Two Flight Management Guidance Computers (FMGC)
‐ Two Multipurpose Control and Display Units (MCDU) (third MCDU optional)
‐ One Flight Control Unit (FCU)
‐ Two Flight Augmentation Computers (FAC).
What are the two available types of guidance and which has priority?
1) Selected
2) Managed
- Selected Guidance always has priority
What are the main databases of the FMGC?
1) Navigation database (updated every 28 days)
2) Airline Modifiable Information (AMI)
3) Aircraft Performance Database (not modifiable by the airline)
4) Magnetic Variation Database
5) User defined Database (ie. crew defined waypoints, runways, navaids, routes)
Functions of the Flight Augmentation Computers (FAC)
• Yaw function
‐ Yaw damping and turn coordination
‐ Rudder trim
‐ Rudder travel limitation
• Flight envelope function
‐ PFD speed scale management
▪ Minimum/maximum speed computation
▪ Maneuvering speed computation
‐ Alpha-floor protection
• Low-Energy Aural Alert function
• Windshear detection functionModes of FMGS Operation
‐ Dual mode (the normal mode)
* two FMGCs are synchronized: each performs its own computations and exchanges data with the other through a crosstalk bus
‐ Independent mode
- Each FMGC being controlled by its associated MCDU
- In flight makes the same entries on both MCDUs
‐ Single mode (using one FMGC only)
- automatically selected when one FMGC fails
- both MCDUs control the operative FMGC
‐ Back–up navigation mode
* can be selected after both FMGCs fail * provides flight planning, aircraft positions, waypoint sequencing, and displays flight plan on ND
How long do values remain on the FCU before returning do dashes (managed mode)
- 45 s on the HDG/TRK and V/S windows
- 10 s on the SPD/MACH window
What are the different Protection Speeds?
- Vα PROT : Angle of attack protection speed - Corresponds to the angle of attack at which the angle of attack protection becomes active (top of a black and amber strip in normal law)
- Vα MAX : Maximum angle of attack speed - Corresponds to the maximum angle of attack that may be reached in pitch normal law (top of a red strip in normal law)
- Vsw : Stall warning speed (red and black strip when not in normal law)
- VMAX : equal to VMO/MMO, VLE or VFE (bottom of a red and black strip)
Default Area RNP Values
EN ROUTE: 2.0 nm
TERMINAL: 1.0 nm
APPROACH: GPS 0.3 nm OTHER CASES 0.5 nm
Meaning of NAV ACCURACY HIGH and LOW
‐ If the EPU (Estimated Position Uncertainty) does not exceed the RNP (Required Navigation Performance), accuracy is HIGH
‐ If the EPU exceeds the RNP, accuracy is LOW
IRS Alignment times
normal alignment: 10 min
fast alignment: 30 s
When does FMGC consider an Engine Out condition?
‐ One engine master switch off, or
‐ N2 below idle, or
‐ One thrust lever angle is below 5 ° with the other above 22 °, or
‐ The FADEC shows an engine fault
On the PFD when is the FD vertical bar replaced by with a yaw bar?
Below 30 ft during landing and takeoff, when a localizer is available
When are FDs automatically engaged during flight?
- in SRS/GA TRK modes at go-around engagement
- in the case of a TCAS Resolution Advisory
SRS Engagement Conditions
Automatically when:
‐ V2 has been inserted in the MCDU PERF TAKEOFF page
‐ The slats are extended
‐ The aircraft has been on ground for at least 30 s
