What is CPC on Airbus A320? (Cabin Pressure Controller)

The Cabin Pressure Controller (CPC) is a crucial component of the Airbus A320 aircraft’s environmental control system. It is responsible for regulating and maintaining the optimal cabin pressure throughout the flight. Cabin pressure affects the comfort and safety of passengers and crew, as well as the structural integrity of the aircraft. Without a properly functioning CPC, the cabin pressure could fluctuate, leading to discomfort, potential health issues, and even structural damage to the aircraft.

The CPC constantly monitors the cabin pressure and adjusts the air supply accordingly to maintain a safe and comfortable atmosphere inside the aircraft. It works in conjunction with other systems, such as the cabin pressure sensors and the air conditioning system, to ensure the cabin pressure remains within specified limits.

How Does the Cabin Pressure Controller Work?

The Cabin Pressure Controller operates based on a set of parameters and algorithms programmed into its control system. It continuously measures the cabin pressure using pressure sensors located throughout the aircraft. These sensors provide real-time feedback on the pressure inside the cabin.

The CPC compares the actual cabin pressure with the desired pressure, which is typically set based on the aircraft’s altitude. It then adjusts the air supply to maintain the desired pressure. If the cabin pressure deviates from the desired level, the CPC commands the air supply system to make necessary adjustments, such as increasing or decreasing the flow of air into the cabin.

Importance of a Reliable Cabin Pressure Controller

Having a reliable Cabin Pressure Controller is of utmost importance for the safety and well-being of everyone on board an Airbus A320. A malfunctioning or inaccurate CPC can lead to various issues:

1. Passenger Comfort: Inaccurate cabin pressure can cause discomfort for passengers, leading to symptoms such as ear pain, headaches, and dizziness. A properly functioning CPC ensures a comfortable flight experience, minimizing any adverse effects passengers may experience due to changes in cabin pressure.

2. Altitude Sickness: When flying at high altitudes, the air pressure outside the aircraft decreases. If the cabin pressure is not adjusted accordingly, it can lead to altitude sickness symptoms among passengers and crew. These symptoms may include nausea, fatigue, and difficulty breathing. The CPC plays a crucial role in maintaining a safe and suitable cabin pressure, minimizing the risk of altitude sickness.

3. Structural Integrity: Fluctuations in cabin pressure can exert stress on the aircraft’s fuselage, compromising its structural integrity. An accurate and reliable CPC ensures that the pressure remains within safe limits, preventing any potential damage to the aircraft due to excessive pressure differentials.


The Cabin Pressure Controller (CPC) is a vital component of the Airbus A320 aircraft’s environmental control system. It regulates and maintains the cabin pressure, ensuring a comfortable and safe environment for passengers and crew. By constantly monitoring and adjusting the air supply, the CPC keeps the cabin pressure within specified limits, minimizing discomfort and potential health risks. A reliable CPC is essential for a smooth and trouble-free flight experience. Passengers can rest assured knowing that the aircraft’s environmental control system, including the Cabin Pressure Controller, is working diligently to provide a comfortable and safe journey.

For More: What is CIDS on Airbus A320? (Cabin Intercommunication Data System)