Failure analysis of aircraft Cabin Pressure Control System

The Cabin Pressure Control System (CPCS) was one of the critical executive systems onboard. Its reliability directly influenced the safety of the pilot and the aircraft. In this paper, the mathematical and simulation models of CPCS were established on the basis of the constitution of CPCS and its working principle. Through simulating normal and failure states of CPCS, parameters of the cabin pressure in various conditions were obtained. The results indicated that if the CPCS worked improperly, the cabin pressure exceeded the safe altitude 2.4 kilometers, the rate of the pressure went beyond the range from - 1.09KPa/min to 1.83KPa/min, and the differential pressure was out of 56.3KPa. Therefore, the overmuch pressure rate and low pressure environment might lead injury or death to the pilots and cabin-passengers. The excessive differential pressure would collapse the airplane structure. Consequently, when CPCS fails, the pilot must take immediate operations, descend the aircraft to the safe altitude or land rapidly in order to avoid fatal accidents.