civil transports, and the high noise levels of rotorcraft inhibit their ability to increase the capacity of the air transportation system.

In decades past, advances in military aviation were the source of many advances in civil aviation, most notably the swept-wing jet transport. More recently, military aviation R&T development funds have been reduced, and the rate at which new military aircraft are developed has greatly declined. In some cases, advances in civil aviation are being transferred to military applications, and dominance of the skies will be greatly affected by the results of civil aeronautics research. A more capable air transportation system could also enhance homeland security. For example, a next-generation air transportation system that uses a network-based approach to communications and the exchange of information would allow surveillance data collected from various air traffic sensors to provide the same comprehensive operational picture to all systems users and monitors, including the DHS and the North American Aerospace Defense Command. The air transportation system of the future should also accommodate routine operations of unmanned air vehicles (UAVs), which are taking an ever larger role in military aviation and will likewise be important to homeland security.

U.S. civil aviation is too important to allow the future to be defined solely by short-term market forces, which are unlikely to produce an efficient system that responds appropriately to user needs. Individual elements of the U.S. air transportation system are owned and operated by competitive companies, government agencies, and private citizens, each with their own motivations, resources, and limitations. Today and in the future, the U.S. air transportation system will not be able to meet the expectations of government, industry, and the public unless ATM equipment and procedures—which generally are owned, controlled, and operated by the federal government—are designed, implemented, and operated as efficiently as possible. In addition, market forces do not provide individual companies with a positive return on investments for research in many areas that are important to public well-being, such as safety, noise, emissions, speed, and basic research. Companies cannot make a business case for supporting an appropriate level of research in these areas, especially when the risk is high and/or a long research program is required to develop commercial applications. NASA, the FAA, and other government agencies must support key noncompetitive and precompetitive research to ensure that the U.S. air transportation system continues to benefit the United States. This is consistent with traditional practices of the FAA and NASA and the legislative charters for these agencies.


The U.S. air transportation system can be viewed from four perspectives:

  • Operational. How does the system function in terms of different phases of operation (takeoff, en route, approach, and landing) and different geographical areas of operation?

  • Aircraft and ground systems. What are the effects on the overall system of changes in the design and performance of individual aircraft and ground facilities, as well as the systems and subsystems that are incorporated within and among various aircraft and facilities?

  • Organizational. How do manufacturers, airlines, pilots, controllers, customers, regulators, and other stakeholders (some with common interests and some with conflicting interests) function together to operate the air transportation system of today and to develop the air transportation system of the future? Also, how well does the current and future air transportation system meet the needs of stakeholders, individually and collectively?

  • International. How does the U.S. air transportation system interact with a global economy, international aviation authorities, and international corporations that are interactive, interdependent, and integrated?

Efforts to improve the existing air transportation system—and to develop the next-generation air transportation system—should take a holistic approach that integrates all of the above perspectives and recognizes that the U.S. air transportation system is a complex interactive system that is more than the sum of its parts.1


For the last 50 years, the National Research Council (NRC) has conducted decadal surveys in astronomy, prioritizing research projects to be undertaken in the next 10 years.2 When the latest astronomy survey was released in 2001 (NRC, 2001), all of the large and many of the moderate-sized programs recommended in the preceding report (NRC, 1991) had been enacted. More recently, NASA commissioned additional decadal surveys in the fields of solar and space physics (NRC, 2003a), planetary science (NRC, 2003c), and Earth science (NRC, 2005). The recently


As used in this report, complex interactive systems (or a system of systems) refer to adaptive systems consisting of a large, widespread collection or network of independent systems functioning together to achieve a common purpose. Complex interactive systems are distinguished from large, monolithic systems by the independent functioning of their components, which provides freedom for existing components to evolve and new components to emerge independent of a central configuration control authority. Complex interactive systems also tend to be distributed over a large geographic extent and require effective communications and coordination protocols for the various components to interact efficiently (Maier, 2006).


The research strategies outlined in these reports are decadal surveys in the sense that they are based on thoughtful examinations of research requirements over the subsequent 10 years.

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement