Although the U.S. aeronautics industry has been one of the undisputed success stories in global competitiveness throughout the latter half of this century and is currently one of the largest positive industrial contributors to the U.S. balance of trade, long-term strategic planning is necessary to ensure that the United States retains a strong and competitive aeronautics industry in the future. Recognizing that a long-term strategic plan for aeronautics requires a broad-based national perspective that includes the needs of users and consumers, the National Research Council conducted a workshop that would bring together experts from industry, government, and academia to analyze a number of possible scenarios for aeronautics 15 to 25 years hence. The results of the workshop, which are discussed in this book, focus on potential needs and opportunities for aviation and aeronautics in the future and their implications for several broad areas of technology development. These areas include new types of aircraft, improved system integration in aircraft design manufacturing and operations, passenger and crew safety and security, operating efficiency and cost effectiveness, environmental compliance and noise abatement, and access to space.

After the completion of the National Research Council (NRC) report, Maintaining U.S. Leadership in Aeronautics: Scenario-Based Strategic Planning for NASA's Aeronautics Enterprise (1997), the National Aeronautics and Space Administration (NASA) Office of Aeronautics and Space Transportation Technology requested that the NRC remain involved in its strategic planning process by conducting a study to identify a short list of revolutionary or breakthrough technologies that could be critical to the 20 to 25 year future of aeronautics and space transportation. These technologies were to address the areas of need and opportunity identified in the above mentioned NRC report, which have been characterized by NASA's 10 goals (see Box ES-1) in "Aeronautics & Space Transportation Technology: Three Pillars for Success" (NASA, 1997). The present study would also examine the 10 goals to determine if they are likely to be achievable, either through evolutionary steps in technology or through the identification and application of breakthrough ideas, concepts, and technologies.