Abel Danger: Russian Airliner With 224 on Board Crashes in Egypt
Oct 31, 2015
http://bit.ly/1PcigA3

Anonymous
Oct 31, 2015 at 3:44 AM
Airbus aircraft designs subsequent to the A300/A310 are almost exclusively controlled by fly-by-wire equipment. These newer aircraft, including the AIRBUS A-320, A330, A340, A350 and A380 operate under Airbus flight control laws. There are some differences in the electrical architecture, the number and the naming of the flight control computers between types.

As an example, the A320 has a total of seven flight control computers - two ELACs (Elevator Aileron Computer), three SECs (Spoilers Elevator Computer) and two FACs (Flight Augmentation Computers) - whereas the A330 has a total of five computers - three PRIMs (Flight Control Primary Computer) and two SECs (Flight Control Secondary Computer). On both aircraft, a single flight control computer is capable of providing complete aircraft control in the most basic of Airbus control laws, Direct Law. Mechanical Back Up is incorporated into the system design to allow limited control of the aircraft while recovering from a temporary total electrical failure. 



The flight controls on Airbus fly-by-wire aircraft are all electronically controlled and hydraulically activated. Some surfaces, such as the rudder and the horizontal stabilizer, can also be mechanically controlled. While in normal flight the computers act to prevent excessive forces in the pitch and roll axes. The following discussion is based on the A330 but much of the information also applies to other Airbus types.