Civil Aircraft Cabin Pressure System Decompression Calculation and Analysis

Abstract

This paper presents a comprehensive analysis of decompression scenarios in civil aircraft cabin pressure systems, focusing on calculation methodologies and safety assessments. The study addresses potential risks arising from structural breaches, pressure regulation failures, and supply system malfunctions, which could lead to hazardous cabin altitude increases. By employing orifice flow theory and dynamic valve adjustment models, the research calculates critical leakage areas under various conditions, including different PACK air supply statuses and cabin altitude warning scenarios. The results demonstrate compliance with airworthiness regulations such as CCAR 25.841, ensuring that cabin altitude thresholds (e.g., 15,000 feet) are not exceeded during system failures. The findings provide essential insights for optimizing emergency descent strategies, enhancing structural redundancy, and supporting airworthiness certification processes.