[gingerbread-man]

I stumbled upon this site when researching flight control algorithms for small UAVs. It appears to be an out-of-date reference for commercial pilots seeking type ratings for the Airbus A320 family. Link to a collection of A320 system schematics and diagrams: http://www.airbusdriver.net/airbus_studyaids.htm

[PaulHoule]

The reason for all these modes is that they depend on having sensors working. For instance ideally you have the angle-of-attack vanes working and airspeed sensors working and with that you can guarantee that the plane is not going to stall.

If you don't have those sensors the control system can offer less certainty and less amenity.

A similar situation exists with the engine control unit in an automobile which uses the oxygen sensor to know it is injecting just the right amount of fuel into the cylinders but won't leave you stranded if the sensor fails.