Here are the key differences between fly-by-wire systems and traditional mechanical flight controls ¹:

- *Electronic interface*: Fly-by-wire systems replace traditional manual flight controls with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires, and flight control computers determine how to move the actuators at each control surface to provide the ordered response.

- *Weight*: Fly-by-wire aircraft can be lighter than a similar design with conventional controls because of the lower overall weight of the system components.

- *Automatic stability systems*: Fly-by-wire control systems allow aircraft computers to perform tasks without pilot input. Automatic stability systems operate in this way.

- *Safety and redundancy*: While traditional mechanical or hydraulic control systems usually fail gradually, the loss of all flight control computers immediately renders the aircraft uncontrollable. For this reason, most fly-by-wire systems incorporate either redundant computers or some kind of mechanical or hydraulic backup or a combination of both.

- *Legislation*: The Federal Aviation Administration (FAA) of the United States has adopted the RTCA/ DO-178C, titled "Software Considerations in Airborne Systems and Equipment Certification", as the certification standard for aviation software.

- *Efficiency of flight*: For airliners, flight-control redundancy improves their safety, but fly-by-wire control systems, which are physically lighter and have lower maintenance demands than conventional controls also improve economy, both in terms of cost of ownership and for in-flight economy.

- *Engine digital control*: The advent of FADEC (Full Authority Digital Engine Control) engines permits operation of the flight control systems and autothrottles for the engines to be fully integrated.