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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.

Potential hazard

  1. Interactions among various stakeholders are not given adequate attention
  2. Gaps and overlaps in organizational responsibilities
  3. Hardware failures
  4. Ineffective human-machine interfaces
  5. Organizational breakdown
  6. Breakdown in communications among operators
  7. Human confirmation biases
  8. Failure to capture multiple interacting agents across highly heterogeneous organizational levels
  9. Nature of complex systems often leads designers to withhold descriptions of system architectures that front-line personnel may need to make sense of the behavior they are observing.
  10. Stove-piped safety analyses: Safety assessments for ATM, airports, pilots, and controllers are frequently handled using different approaches.
  11. Human reliability assessments are often done in a binary manner rather than in a more nuanced fashion.

Corroborating sources and comments

Maintaining U.S. Leadership in Aeronautics: Breakthrough Technologies to Meet Future Air and Space Transportation Needs and Goals (1998); Air Transportation System Technology – PARADIGM SHIFT IN THE AIR TRANSPORTATION SYSTEM

EU Aviation Safety and Certification of New Operations and Systems project (ASCOS)

Many innovative technologies and operational concepts are not developed for reasons of implementation risk or too much time to reach implementation. Many operators and users are eager to make use of new developments. To ease the introduction of safety enhancement systems and operations, a innovative approach towards certification is required that:

  • Is more flexible with regard to the introduction of new products and operations;
  • Is more efficient, in terms of cost, time and safety, than the current certification processes;
  • Considers safety impact of all aviation system elements and the entire system life-cycle in a complete integrated way.

Moving towards performance based regulation, based upon agreed safety performance in combination with a risk based approach to standardization, is expected to lead to improvements in the way that safety risks are controlled. ?Anticipating future risks by using a “proactive approach” helps to make the certification process robust to new developments. ??Introducing ‘continuous safety monitoring’ ensures that new essential safety data is effectively used immediately after it is available.

The objective of ASCOS is to develop innovative certification process adaptations and supporting safety driven design methods and tools to ease the certification of safety enhancement systems and operations while, at the same time, increasing safety. ASCOS aims to better account for the human element, already from the early stages of the certification process, and thus reducing consequences of human error and increasing safety. The project will follow a total system approach, dealing with all aviation system elements in an integrated way over the complete life-cycle.

ASCOS coordinated with the SAE S-18 Airplane Safety Assessment Committee and the EUROCAE Working Group 63 “Complex aircraft systems” in Rome, Italy, on 17 October 2012.

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