The road ahead: present and future trends in global civil aircraft regulations

In the past century, the complexity of civil aircraft has grown exponentially to offer higher performance and enhanced operational capabilities, including improved reliability, maintainability, and other critical “-ilities.” While this increased complexity enables greater functionality, it often comes at the cost of prolonged development schedules and escalated budgets. Aircraft complexity is intrinsically tied to an evolving web of requirements, encompassing internal demands driven by market profitability and external mandates from regulatory bodies. To understand the dynamics shaping the complexity of civil aircraft, this paper examines the trends in airworthiness and environmental regulations in the three largest aviation markets: the United States, China, and Europe. Regulations were extracted and analyzed from governmental archives to track trends in the number and nature of aircraft requirements in the last two decades. Additional insights were derived from recommendations by the International Civil Aviation Organization and SAE International, as well as environmental objectives set by respective governments, to predict future regulatory trends. Since 2003, an increase in the number of regulations of 33% and 23% was recorded for the US Federal Aviation Administration and the European Aviation Safety Agency, respectively. More recently, airworthiness requirements displayed greater stability and international harmonization than environmental regulations, which were identified as key drivers of future regulatory reforms and global inconsistencies. To characterize how regulations impact both the aircraft as a system and through its subsystems, this study relies on a case study of the regulations impacting the design of landing gears, where system and functional requirements contributed to more than 80% of the relevant regulations. Through this multi-layered and international approach, this paper provides a comprehensive understanding of how evolving regulations shape the complexity of civil aircraft, offering insights that can guide future policy development and industry innovation.