What are the three laws involved in the flight control system?

The three laws involved in the flight control system of the A320 are Normal Law, Alternate Law, and Direct Law.

Normal Law is the primary mode of operation and provides enhanced flight envelope protection. It ensures that the aircraft remains within safe operating limits by automatically limiting parameters like bank angle and pitch attitude. This law allows for the most intuitive control of the aircraft, making it easier for pilots to fly.

Alternate Law is activated when certain failures occur that prevent the systems needed for Normal Law from functioning correctly. While it still offers some protections, they are reduced compared to Normal Law. For instance, there is a loss of some envelope protection and aircraft may respond with a greater degree of freedom, which means pilots must be more careful in managing the aircraft's performance.

Direct Law is engaged when there are significant failures, particularly in both the flight control computers and some of the control surfaces. In this mode, the flight controls behave more like a conventional aircraft without the protections offered by the other laws. Pilot input is directly translated into control surface movements, which requires greater pilot skill and attention to manage aircraft behavior.

This combination of laws allows the A320's fly-by-wire system to accommodate various system statuses while enhancing safety and performance for the pilots.