The function of the altitude controller in a cabin atmosphere control system is to maintain cabin altitude by regulating which component?

The altitude controller is primarily responsible for maintaining cabin altitude by regulating the outflow valve. The outflow valve plays a crucial role in managing the pressure within the cabin by controlling the amount of cabin air that escapes to the external environment.

When the aircraft climbs to higher altitudes, the outflow valve adjusts to allow air to exit the cabin at a rate that maintains a safe and comfortable cabin pressure, preventing it from rising excessively. Conversely, during descent, the outflow valve can close or restrict airflow to ensure that cabin pressure is maintained at an appropriate level as the aircraft descends.

Understanding that the altitude controller utilizes the outflow valve to modulate cabin pressure highlights its importance in ensuring passenger comfort and safety during different phases of flight. The other components listed—compressor, inflation valve, and air supply valve—play roles in air circulation and pressurization, but it is the outflow valve that directly impacts the cabin altitude setting under the control of the altitude controller.