Collaboration between the federal government and the aviation industry has led to reductions in aviation emissions, but growing air traffic has partially offset these reductions. The Federal Aviation Administration (FAA), together with the National Aeronautics and Space Administration (NASA), the Environmental Protection Agency (EPA), and others, is working to increase the efficiency, safety, and capacity of the national airspace system and at the same time reduce aviation emissions, in part, by transforming the current air traffic control system to the Next Generation Air Transportation System (NextGen). This effort involves new technologies and air traffic procedures that can reduce aviation emissions and incorporates research and development (R & D) on emissions-reduction technologies. Reducing aviation emissions is important both to minimize their adverse health and environmental effects and to alleviate public concerns about them that could constrain the expansion of airport infrastructure and aviation operations needed to meet demand. This testimony addresses (1) the scope and nature of aviation emissions, (2) the status of selected key federal efforts to reduce aviation emissions, and (3) next steps and challenges in reducing aviation emissions. The testimony updates prior GAO work with FAA data, literature reviews, and interviews with agency officials, industry and environmental stakeholders, and selected experts. Aviation contributes a modest but growing proportion of total U.S. emissions, and these emissions contribute to adverse health and environmental effects. Aircraft and airport operations, including those of service and passenger vehicles, emit ozone and other substances that contribute to local air pollution, as well as carbon dioxide and other greenhouse gases that contribute to climate change. EPA estimates that aviation emissions account for less than 1 percent of local air pollution nationwide and about 2.7 percent of U.S. greenhouse gas emissions, but these emissions are expected to grow as air traffic increases. Two key federal efforts, if implemented effectively, can help to reduce aviation emissions--NextGen initiatives in the near term and research and development over the longer term. For example, NextGen technologies and procedures, such as satellite-based navigation systems, should allow for more direct routing, which could improve fuel efficiency and reduce carbon dioxide emissions. Federal research and development efforts--led by FAA and NASA in collaboration with industry and academia--have achieved significant reductions in aircraft emissions through improved aircraft and engine technologies, and federal officials and aviation experts agree that such efforts are the most effective means of achieving further reductions in the longer term. Federal R & D on aviation emissions also focuses on improving the scientific understanding of aviation emissions and developing lower-emitting aviation fuels. Next steps in reducing aviation emissions include managing NextGen initiatives efficiently; deploying NextGen technologies and procedures as soon as practicable to realize their benefits, including lower emissions levels; and managing a decline in R & D funding, in part, by setting priorities for R & D on NextGen and emissions-reduction technologies. Challenges in reducing aviation emissions include designing aircraft that can simultaneously reduce noise and emissions of air pollutants and greenhouse gases; encouraging financially stressed airlines to purchase more fuel-efficient aircraft and emissions-reduction technologies; addressing the impact on airport expansion of more stringent EPA air quality standards and growing public concerns about the effects of aviation emissions; and responding to proposed domestic and international measures for reducing greenhouse gases that could affect the financial solvency and competitiveness of U.S. airlines.

This report is a guide for airport operators on effective procedures for using air quality models in combination with on-site measurement equipment to prepare a comprehensive assessment of air pollutant concentrations in the vicinity of airports. It is designed to help practitioners generate information desired by local communities as they seek to develop more detailed local air quality assessments as well as respond to regulatory needs, including those of the National Environmental Policy Act (NEPA). The guide provides in-depth information on the capabilities and limitations of modeling and measurement tools, adding to an increasing knowledge base concerning preparation of air quality assessments near airports. Starting with the Federal Aviation Administration's (FAA) regulatory EDMS/AEDT, it describes how best to use available models, in combination with potential on-site monitoring programs, to conduct air quality assessments. Detailed information on the monitoring campaigns and modeling assessments is included in a set of appendices that accompany the guide. The appendices (available in CRP-CD-115) describe the models tested and the various equipment used to collect data, the rationale behind the selection of Washington Dulles International Airport as a case study application, and the components and steps involved in the measurement campaigns, and include an assessment of the various model outputs--

The Principles and Practice of International Aviation Law provides an introduction to, and demystification of, the private and public dimensions of international aviation law. Unlike other global sectors, the air transport industry is not governed by a discrete area of the law, but by disparate transnational regulatory instruments. Everything from the routes that an international air carrier can serve to the acquisition of its fleet and its liability to passengers and shippers for incidents arising from its operations can be the object of bilateral and multilateral treaties that represent diverse and often contradictory interests. Beneath this are hundreds of domestic regulatory regimes that also apply national and international rules in disparate ways. The result is an agglomeration of legal cultures that can leave even experienced lawyers and academics perplexed. By combining classical doctrinal analysis with insights from newer disciplines such as international relations and economics, the book maps international aviation law's complex terrain for new and veteran observers alike.

This book analyses the political, economic and managerial challenges for policy makers and the air transport industry as they face climate change. Based on an overview of the scientific background and technological options for emissions reduction, Aviation and Climate Change provides an in-depth assessment of environmental regulation and management. It provides an up-to-the-minute analysis of the effects of aviation on climate change, and an economic analysis of policies to reduce or eliminate greenhouse gas emissions. The main emphasis of the book is on the economic mechanisms used to lessen emissions – carbon taxes, emissions trading schemes and offset schemes. It pays particular attention to the ways these policies work, and to the interaction between them – for instance, the interaction between taxes and emissions trading schemes. One feature of the book is that it analyses the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) which has been developed by ICAO for international aviation, and which is due to commence operation shortly. The advantages and disadvantages of this controversial scheme are discussed. This book will be of interest to researchers in diverse areas (economics, political science, engineering, natural sciences), to air transport policy makers, and to managers in the aviation industry.