What directly affects the opening of the outflow valve in cabin pressure control?

The opening of the outflow valve in cabin pressure control is directly influenced by the cabin pressure control setting. This setting is crucial because it determines how much air is allowed to leave the cabin, thereby regulating the cabin pressure during various phases of flight.

The cabin pressure control system operates based on predetermined settings, ensuring that the pressure inside the aircraft is maintained at safe levels for passenger comfort and safety. When the pressure control setting dictates a need for pressure adjustment, it signals the outflow valve to open or close accordingly, which directly affects the cabin pressure.

Adjustments to this setting can be made by the flight engineer or auto-pressure systems based on altitude changes and other operational considerations, thereby emphasizing the importance of the control setting in managing outflow valve function.