Increasing complexities within future air transportation systems

There is concern that the complexity of a system of systems will exceed our ability to truly understand its characteristics and mitigate safety problems produced by the complexity itself. The civil aviation infrastructure is extraordinarily dependent on computer-telecommunications information systems. Some of the most prominent and widely used systems include those for air traffic control, navigation, reservations, and aircraft flight control. Increasingly, these information systems have become critical to the spectrum of activities in aviation.

Because of the complex interactions between economic, political, sociological, and technological forces in the air transportation system, it has been extremely difficult to predict the impact of new technologies or changes in operational procedures on operations and safety. Consequently, there is a strong tendency within the system to maintain the status quo, and new technologies or operating procedures have been limited to incremental improvements. Predicting the impact of technical or operational/procedural changes on a comprehensive basis will require improved methods and models for evaluating the safety of potential changes to the air transportation system. As a basis for the development of methods and models that encompass the technical, procedural, and socioeconomic complexity and dynamism of the system, NASA, industry, and the FAA should prepare a formal [baseline] representation of existing rules and procedures that govern system operations.

Regulations intended to promote safety can sometimes become barriers to technological and procedural changes. For example, many commuter aircraft were designed as 19 passenger aircraft simply because FAA safety regulations require a flight attendant on aircraft designed for 20 or more passengers. This economic factor impacted aircraft design decisions more than performance or economic improvements that may have been possible from the development of slightly larger aircraft.

Commercial aviation at the beginning of the 21st century is a highly complex, system of systems. It features airborne, ground, and space-based technology systems, complex supply chains, an enabling regulatory environment, operators at many levels, and last but not least, a complex web of operational procedures and training systems for operators. The complex systems such as commercial aviation possess the fundamental characteristics of diversity, connectedness, interdependence, adaptation, non-linearity, and emergent behavior (Dr. Scott Page of the University of Michigan). Complex systems can be good and bad. As a result of their distributed architectures and redundancies, they can be extraordinarily resilient. On the other hand, the interdependent relationships and characteristics of emergent behavior within complex systems can result in undesired states that can propagate rapidly through the system or create singular, spectacular tragic events.