Commercial Aircraft Propulsion
and Energy Systems Research
Reducing Global Carbon Emissions
Committee on Propulsion and Energy Systems to Reduce Commercial Aviation Carbon Emissions
Aeronautics and Space Engineering Board
Division on Engineering and Physical Sciences
THE NATIONAL ACADEMIES PRESS
Washington, DC
THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001
This report is based on work supported by Contract NNH10CD04B TO#12 with the National Aeronautics and Space Administration. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
International Standard Book Number-13: 978-0-309-44096-7
International Standard Book Number-10: 0-309-44096-3
Digital Object Identifier: 10.17226/23490
Cover design by Tim Warchocki.
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2016. Commercial Aircraft Propulsion and Energy Systems Research: Reducing Global Carbon Emissions. Washington, DC: The National Academies Press. doi:10.17226/23490.
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OTHER RECENT REPORTS OF THE AERONAUTICS AND SPACE ENGINEERING BOARD
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Autonomy Research for Civil Aviation: Toward a New Era of Flight (ASEB, 2014)
3D Printing in Space (ASEB, 2014)
Pathways to Exploration: Rationales and Approaches for a U.S. Program of Human Space Exploration (ASEB with Space Studies Board [SSB], 2014)
Continuing Kepler’s Quest: Assessing Air Force Space Command’s Astrodynamics Standards (ASEB, 2012)
NASA Space Technology Roadmaps and Priorities: Restoring NASA’s Technological Edge and Paving the Way for a New Era in Space (ASEB, 2012)
NASA’s Strategic Direction and the Need for a National Consensus (Division on Engineering and Physical Sciences, 2012)
Recapturing NASA’s Aeronautics Flight Research Capabilities (SSB and ASEB, 2012)
Reusable Booster System: Review and Assessment (ASEB, 2012)
Solar and Space Physics: A Science for a Technological Society (SSB with ASEB, 2012)
Limiting Future Collision Risk to Spacecraft: An Assessment of NASA’s Meteroid and Orbital Debris Programs (ASEB, 2011)
Preparing for the High Frontier—The Role and Training of NASA Astronauts in the Post-Space Shuttle Era (ASEB, 2011)
Advancing Aeronautical Safety: A Review of NASA’s Aviation Safety-Related Research Programs (ASEB, 2010)
Capabilities for the Future: An Assessment of NASA Laboratories for Basic Research (Laboratory Assessments Board with SSB and ASEB, 2010)
Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies (SSB with ASEB, 2010)
Forging the Future of Space Science: The Next 50 Years: An International Public Seminar Series Organized by the Space Studies Board: Selected Lectures (SSB with ASEB, 2010)
Life and Physical Sciences Research for a New Era of Space Exploration: An Interim Report (SSB with ASEB, 2010)
Recapturing a Future for Space Exploration: Life and Physical Sciences Research for a New Era (ASEB, 2010)
Limited copies of ASEB reports are available free of charge from:
Aeronautics and Space Engineering Board
Keck Center of the National Academies of Sciences, Engineering, and Medicine
500 Fifth Street, NW, Washington, DC 20001
(202) 334-3477/aseb@nas.edu
www.nationalacademies.org/ssb/ssb.html
COMMITTEE ON PROPULSION AND ENERGY SYSTEMS TO REDUCE COMMERCIAL AVIATION CARBON EMISSIONS
KAREN A. THOLE, Pennsylvania State University, Co-Chair
WOODROW WHITLOW, JR., Cleveland State University, Co-Chair
MEYER J. BENZAKEIN, Ohio State University
R. STEPHEN BERRY, University of Chicago
MARTY K. BRADLEY, Boeing Commercial Airplanes
STEVEN J. CSONKA, Commercial Aviation Alternative Fuels Initiative
DAVID J. H. EAMES, Rolls-Royce North America (retired)
DANIEL K. ELWELL, Elwell and Associates, LLC
ALAN H. EPSTEIN, Pratt & Whitney
ZIA HAQ, U.S. Department of Energy
KAREN MARAIS, Purdue University
JAMES F. MILLER, Argonne National Laboratory
JOHN G. NAIRUS, Air Force Research Laboratory
STEPHEN M. RUFFIN, Georgia Institute of Technology
HRATCH G. SEMERJIAN, National Institute of Standards and Technology
SUBHASH C. SINGHAL, Pacific Northwest National Laboratory
Staff
ALAN C. ANGLEMAN, Senior Program Officer, Study Director
MICHAEL H. MOLONEY, Director, Aeronautics and Space Engineering Board and Space Studies Board
ANESIA WILKS, Senior Program Assistant
CHARLES HARRIS, Research Associate
AERONAUTICS AND SPACE ENGINEERING BOARD
LESTER L. LYLES, The Lyles Group, Chair
PATRICIA GRACE SMITH, Aerospace Consultant, Vice Chair
ARNOLD D. ALDRICH, Aerospace Consultant
BRIAN M. ARGROW, University of Colorado, Boulder
STEVEN J. BATTEL, Battel Engineering
MEYER J. BENZAKEIN, Ohio State University
BRIAN J. CANTWELL, Stanford University
ELIZABETH R. CANTWELL, Arizona State University
EILEEN M. COLLINS, Space Presentations, LLC
MICHAEL P. DELANEY, Boeing Commercial Airplanes
EARL H. DOWELL, Duke University
ALAN H. EPSTEIN, Pratt & Whitney
KAREN FEIGH, Georgia Institute of Technology
PERETZ P. FRIEDMANN, University of Michigan
MARK J. LEWIS, Science and Technology Policy Institute, Institute of Defense Analyses
RICHARD McKINNEY, Independent Consultant
JOHN M. OLSON, Sierra Nevada Corporation
ROBIE I. SAMANTA ROY, Lockheed Martin
AGAM N. SINHA, Ans Aviation International, LLC
ALAN M. TITLE, Lockheed Martin, Advanced Technology Center
DAVID M. VAN WIE, Johns Hopkins University, Applied Physics Laboratory
SHERRIE L. ZACHARIUS, Aerospace Corporation
Staff
MICHAEL H. MOLONEY, Director
CARMELA J. CHAMBERLAIN, Administrative Coordinator
TANJA PILZAK, Manager, Program Operations
CELESTE A. NAYLOR, Information Management Associate
MEG A. KNEMEYER, Financial Officer
SANDRA WILSON, Financial Assistant
Preface
Commercial aviation, like every means of mass transportation, releases carbon dioxide into the atmosphere. Substantial, ongoing investments in air transportation technologies continually increase the efficiency of air transportation, moving passengers and cargo over the same distance with less fuel consumed and, hence, fewer carbon emissions. Even so, given the high demand for commercial air transportation and its expected growth, more effort is needed to mitigate the contribution that commercial aviation makes to climate change.
A great many public and private organizations, including engine and aircraft manufacturers, academia, the National Aeronautics and Space Administration (NASA), the Federal Aviation Administration, the Environmental Protection Agency, and the U.S. Departments of Agriculture, Commerce, Defense, and Energy, are already engaged in developing advanced technologies, policies, and standards that will help reduce carbon emissions from commercial aviation. Accordingly, NASA’s Aeronautics Research Mission Directorate requested that the National Academies of Sciences, Engineering, and Medicine convene a committee to develop a national research agenda for propulsion and energy systems research to reduce commercial aviation carbon emissions. In response, the Aeronautics and Space Engineering Board of the Division on Engineering and Physical Sciences assembled a committee to carry out the assigned statement of task (see Appendix A). The committee members (see Appendix B) met four times during 2015 and early 2016, three times at the Academies’ facilities in Washington, D.C., and once at the Academies’ Irvine, California, facility. As specified in the statement of task, the committee developed a research agenda consisting of a set of high-priority research projects that, if completed by NASA and other interested parties, would advance the four high-priority approaches for developing propulsion and energy system technologies that could be introduced into service during the next 10 to 30 years to reduce global carbon emissions by commercial aviation.
Karen Thole, Co-Chair
Woodrow Whitlow, Jr., Co-Chair
Committee on Propulsion and Energy Systems to Reduce Commercial Aviation Carbon Emissions
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Acknowledgment of Reviewers
This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:
Michael Armstrong, Rolls-Royce North American Technologies,
John R. Birge, University of Chicago,
Bill Borger, W U Borger Consulting,
Fokion N. Egolfopoulos, University of Southern California,
Neil Gehrels, NASA Goddard Space Flight Center,
John Kinney, GE Aviation,
Holger Kuhn, Bauhaus Luftfahrt e.V.,
Louis J. Lanzerotti, New Jersey Institute of Technology,
Jonathan Male, Department of Energy,
George W. Sutton, Analysis and Applications,
Wallace E. Tyner, Purdue University, and
Jeanne Yu, Boeing Commercial Airplanes.
Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations, nor did they see the final draft of the report before its release. The review of this report was overseen by Edward M. Greitzer, Massachusetts Institute of Technology, and Maxine L. Savitz, Honeywell, Inc. (retired), who were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.
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Contents
Carbon Dioxide Emissions from Commercial Aviation
Systemic Challenges to Lowering Global Emissions from Commercial Aviation
Aircraft Systems Complexity and Integration
Report Organization and Prioritization Process
High-Priority Research Projects
Other Potential Approaches and Research Projects
2 AIRCRAFT–PROPULSION INTEGRATION
Advanced Aircraft–Propulsion Integration Concepts
Integration of Aircraft Propulsion and Power Systems
Recommended High-Priority Research Projects
Nacelles for Ultrahigh-Bypass-Ratio Gas Turbines
3 AIRCRAFT GAS TURBINE ENGINES
Opportunities for Reducing Carbon Dioxide
Improving Propulsive Efficiency
Improving Thermodynamic Efficiency
Rationale for Gas Turbine Engine Research
Recommended High-Priority Research Projects
Low-Pressure-Ratio Fan Propulsors
System Studies Conducted by Industry, Government, and Academia
Technology Needs: Status and Projections
Electric Machines and Power Conditioning
Cryogenic Electric Aircraft Power Systems
Application to General Aviation and Commercial Aircraft
Application to General Aviation
Application to Commuter Aircraft
Application of Electric Propulsion to Regional and Single-Aisle Aircraft
Applications of Electric Propulsion to Twin-Aisle Aircraft
Rationale for Turboelectric Propulsion Research
Recommended High-Priority Research Projects
5 SUSTAINABLE ALTERNATIVE JET FUELS
Ongoing Efforts to Define a Federal Alternative Jet Fuel R&D Strategy
Rationale for Sustainable Alternative Jet Fuels
Recommended High-Priority Research Projects
6 FINDINGS, RECOMMENDATIONS, ROLES, AND RESOURCES
Approaches for Reducing CO2 Emissions
Aircraft–Propulsion Integration Research
Turboelectric Propulsion Research
Sustainable Alternative Jet Fuels Research
High-Priority Research Projects
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