How is the outflow valve actuated?

The outflow valve is actuated by DC electric motors, which are commonly used in various aircraft systems due to their reliability and efficiency. DC electric motors provide precise control over the valve's positioning, enabling the system to respond quickly and accurately to changes in demand for cabin pressure management. This mechanism allows for better automation and integration into the aircraft's environmental control systems.

In contrast, pneumatic pressure may be used for other systems within an aircraft but is not the primary means of actuating the outflow valve. Hydraulic systems, while prevalent in many moving components of an aircraft, are typically reserved for more significant mechanical actions requiring higher force, rather than the fine control needed for the outflow valve. AC electric motors, while also useful in other applications, would not be ideal for this specific function due to their operational characteristics and the requirements of the outflow valve actuation process.