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Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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Uninhabited Air Vehicles

Enabling Science for Military Systems

Committee on Materials, Structures, and Aeronautics for Advanced Uninhabited Air Vehicles

National Materials Advisory Board

Aeronautics and Space Engineering Board

Commission on Engineering and Technical Systems

National Research Council

Publication NMAB-495

NATIONAL ACADEMY PRESS
Washington, D.C.

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
×

National Academy Press
2101 Constitution Avenue, N.W. Washington, D.C. 20418

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the panel responsible for the report were chosen for their special competencies and with regard for appropriate balance.

This project was conducted under a contract with the Department of Defense and the Air Force Office of Scientific Research. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the view of the organizations or agencies that provided support for the project.

Cover: Courtesy of Ryan Aeronautical Center

International Standard Book Number: 0-309-06983-1

Copies of this report are available from:

National Materials Advisory Board

National Research Council

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Washington, D.C. 20418

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nmab@nas.edu

Copies are available for sale from:
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Copyright 2000 by the National Academy of Sciences. All rights reserved.

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Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
×

THE NATIONAL ACADEMIES

National Academy of Sciences

National Academy of Engineering

Institute of Medicine

National Research Council

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.

The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. William A. Wulf is president of the National Academy of Engineering.

The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. William A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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COMMITTEE ON MATERIALS, STRUCTURES, AND AERONAUTICS FOR ADVANCED UNINHABITED AIR VEHICLES

GORDON SMITH (chair),

Vanguard Research, Inc., Fairfax, Virginia

DANIEL ARNOLD,

The Boeing Company, Seattle, Washington

DANIEL BACKMAN,

GE Aircraft Engines, Lynn, Massachusetts

ALAN H. EPSTEIN,

Massachusetts Institute of Technology, Cambridge

RICHARD F. GABRIEL,

McDonnell Douglas Corporation (retired), San Clemente, California

CHIH-MING HO,

University of California at Los Angeles

ANTHONY K. HYDER,

University of Notre Dame, South Bend, Indiana

ILAN KROO,

Stanford University, Stanford, California

W. RAY MORGAN,

AeroVironment, Simi Valley, California

THOMAS P. QUINN, consultant,

Temple Hills, Maryland

DANNY L. REED,

Institute for Defense Analyses, Alexandria, Virginia

GUNTER STEIN,

Honeywell Technology Center, Minneapolis, Minnesota

TERRENCE A. WEISSHAAR,

Purdue University, West Lafayette, Indiana

DIANNE S. WILEY,

Northrop Grumman, Pico Rivera, California

National Research Council Staff

THOMAS E. MUNNS, study director,

National Materials Advisory Board (until December 10, 1999)

ARUL MOZHI, senior program officer,

National Materials Advisory Board

ALAN ANGLEMAN, senior program officer,

Aeronautics and Space Engineering Board

TERI THOROWGOOD, research associate,

National Materials Advisory Board

JANICE PRISCO, senior project assistant

National Research Council Liaisons

ANTHONY G. EVANS,

Harvard University, Cambridge, Massachusetts (National Materials Advisory Board)

GRACE M. ROBERTSON,

The Boeing Company, Long Beach, California (Aeronautics and Space Engineering Board)

Government Liaison

BRIAN SANDERS,

U.S. Air Force Office of Scientific Research, Washington, D.C.

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
×

NATIONAL MATERIALS ADVISORY BOARD

EDGAR A. STARKE (chair),

University of Virginia, Charlottesville

JESSE L. BEAUCHAMP,

California Institute of Technology, Pasadena

EARL DOWELL,

Duke University, Durham, North Carolina

EDWARD C. DOWLING,

Cleveland Cliffs, Inc., Cleveland, Ohio

THOMAS EAGAR,

Massachusetts Institute of Technology, Cambridge

ALASTAIR GLASS,

Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey

MARTIN E. GLICKSMAN,

Rensselaer Polytechnic Institute, Troy, New York

JOHN A.S. GREEN,

The Aluminum Association, Washington, D.C.

SIEGFRIED S. HECKER,

Los Alamos National Laboratory, Los Alamos, New Mexico

JOHN H. HOPPS,

Morehouse College, Atlanta, Georgia

MICHAEL JAFFE,

New Jersey Center for Biomaterials and Medical Devices, Piscataway

SYLVIA M. JOHNSON,

SRI International, Menlo Park, California

SHEILA F. KIA,

General Motors Research and Development, Warren, Michigan

LIAS KLEIN,

Rutgers, The State University of New Jersey, Piscataway

HARRY A. LIPSITT,

Wright State University, Dayton, Ohio

ALAN G. MILLER,

Boeing Commercial Airplane Group, Seattle, Washington

ROBERT C. PFAHL,

Motorola, Schaumberg, Illinois

JULIA PHILLIPS,

Sandia National Laboratories, Albuquerque, New Mexico

KENNETH L. REIFSNIDER,

Virginia Polytechnic Institute and State University, Blacksburg

JAMES WAGNER,

Case Western Reserve University, Cleveland, Ohio

JULIA WEERTMAN,

Northwestern University, Evanston, Illinois

BILL G.W. YEE,

Pratt and Whitney, West Palm Beach, Florida

RICHARD CHAIT, director

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
×

AERONAUTICS AND SPACE ENGINEERING BOARD

WILLIAM W. HOOVER (chair),

U.S. Air Force (retired), Williamsburg, Virginia

A. DWIGHT ABBOTT,

Aerospace Corporation, Los Angeles, California

RUZENA BAJSCY,

NAE, IOM, University of Pennsylvania, Philadelphia

WILLIAM F. BALLHAUS, JR.,

Lockheed Martin Corporation, Bethesda, Maryland

ANTHONY J. BRODERICK,

aviation safety consultant, Catlett, Virginia

AARON COHEN,

NAE, Texas A&M University, College Station

DONALD L. CROMER,

U.S. Air Force (retired), Lompoc, California

HOYT DAVIDSON,

Donaldson, Lufkin, and Jenrette, New York, New York

ROBERT A. DAVIS,

The Boeing Company (retired), Seattle, Washington

DONALD C. FRASER,

NAE, Boston University, Boston, Massachusetts

JOSEPH FULLER JR.,

Futron Corporation, Bethesda, Maryland

ROBERT C. GOETZ,

Lockheed Martin Skunk Works, Palmdale, California

RICHARD GOLASZEWSKI,

GRA, Inc., Jenkintown, Pennsylvania

JAMES M. GUYETTE,

Rolls-Royce North America, Reston, Virginia

FREDERICK HAUCK,

AXA Space, Bethesda, Maryland

JOHN K. LAUBER,

Airbus Industrie of North America, Washington, D.C.

GEORGE MUELLNER,

The Boeing Company, Seal Beach, California

DAVA J. NEWMAN,

Massachusetts Institute of Technology, Cambridge

JAMES G. O’CONNOR,

NAE, Pratt & Whitney (retired), Coventry, Connecticut

WINSTON E. SCOTT,

Florida State University, Tallahassee

KATHRYN C. THORNTON,

University of Virginia, Charlottesville

DIANNE S. WILEY,

Northrop Grumman, Pico Rivera, California

RAY A. WILLIAMSON,

George Washington University, Washington, D.C.

GEORGE LEVIN, director

Page viii Cite
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Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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Preface

The development of effective and affordable uninhabited air vehicles (UAVs) has become a priority for the U.S. Air Force because UAVs have the potential to perform autonomously under conditions that are not conducive to inhabited aircraft. UAVs will either save human operators from long or monotonous tasks or, more importantly, will preclude risking human pilots in dangerous situations. To be accepted by the military services, UAVs must provide these advantages at significantly lower life-cycle costs than current costs.

The development of optimal UAVs is a complex systems engineering problem. Complicated trade-offs must be made among performance, survivability, autonomy, range, payload, and, perhaps most important, cost. The fundamental driving force behind the development of military UAVs is to reduce substantially the cost of weapon system acquisition and sustainment.

The objectives of this joint study of the National Research Council National Materials Advisory Board and the Aeronautics and Space Engineering Board were (1) to identify needs and opportunities for technology development that have the potential to meet the Air Force’s performance and reliability requirements and reduce costs for “generation-after-next” UAVs and (2) to recommend areas of fundamental research in materials, structures, and aeronautical technologies. The committee focused on technological innovations likely to be ready for development and scale-up in the post-2010 time frame (i.e., ready for use in 2020–2025). The intent is to “leapfrog” current technology development.

To complete its task, the committee reviewed proposed missions and design concepts for advanced UAVs that are anticipated to be operating in the long term and then reviewed key requirements for vehicle structures, flight control systems, propulsion systems, and power systems, based on a range of potential mission

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
×

scenarios. Finally, the committee identified the underlying technological advancements required to meet the performance targets. This report recommends fundamental and applied research for developing a tool box of UAV-unique or UAV-critical technologies that could provide the required performance and reliability while reducing costs.

Comments and suggestions can be sent via electronic mail to nmab@nas.edu or by fax to NMAB at (202) 334-3718.

Gordon Smith, chair

Committee on Materials, Structures, and Aeronautics for Advanced Uninhabited Air Vehicles

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
×

Acknowledgments

The committee would like to thank the presenters and participants in the committee’s data-gathering sessions for this study. Presenters were Peter Worch, consultant; Lt Col Michael Leahy, U.S. Air Force Aeronautical Systems Center; Michael Francis, Aurora Flight Sciences; CDR Michael Eilliamson, Naval Air Systems Command; Julieta Booz, Naval Sea Systems Command; James McMichael, Defense Advanced Research Projects Agency; Rand Bowerman, Army Battle Laboratory; Kevin Niewoehner, National Aeronautics and Space Administration; Heinz Gerhardt, Northrop Grumman; James Lang, Boeing; Charles Kukkonen, Jet Propulsion Laboratory; and Lt Col Walter Price, Defense Advanced Research Projects Agency. The committee would also like to thank the Air force liaison to the committee Maj Brian Sanders, AFOSR.

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 National Research Council’s (NRC’s) Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the authors and the institution in making the 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 participation in the review of this report: Robert Crowe, Virginia Polytechnic and State University; James B. Day, Belcan Engineering Group; Earl Dowell, Duke University; Michael Francis, Aurora Flight Systems; George J. Gleghorn, TRW Space and Technology Corporation (retired); James Mattice, Universal

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
×

Technology Corporation; and Leland Nicolai, Lockheed Martin Skunk Works. While the individuals listed above have provided constructive comments and suggestions, it must be emphasized that responsibility for the final content of this report rests entirely with the authoring committee and the institution.

Finally, the committee gratefully acknowledges the support of the staff of the National Research Council: Thomas Munns, study director, Teri Thorowgood, research associate, Arul Mozhi, senior program officer, and Jan Prisco, administrative assistant, National Materials Advisory Board; Alan Angleman, senior staff officer, Aeronautics and Space Engineering Board; and Carol R. Arenberg, editor, Commission on Engineering and Technical Systems.

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Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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Tables and Figures

TABLES

1-1

 

Major UAV Programs,

 

11

5-1

 

Total Propulsion System Mass for 50-Gram MAV,

 

66

5-2

 

UAV Propulsion Technologies,

 

69

6-1

 

Key Parameters for Space Power Components and Systems Applicable to UAVs,

 

75

6-2

 

Trade-offs among Interacting Technologies for Power Generation,

 

78

FIGURES

1-1

 

Pioneer UAV taking off from the deck of the USS Iowa,

 

12

1-2

 

Hunter reconnaissance and surveillance UAV,

 

13

1-3

 

Predator airborne surveillance, reconnaissance, and target acquisition vehicle,

 

13

1-4

 

Global Hawk during sixth test flight,

 

14

1-5

 

Darkstar high-altitude, long-endurance UAV,

 

15

1-6

 

Outrider tactical UAV,

 

16

2-1

 

Recommended approach to technology prioritization,

 

21

2-2

 

Missions and time frames for operational demonstration recommended by the USAFSAB,

 

23

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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2-3

 

Range of vehicle attributes (from conventional mission to special applications),

 

25

2-4

 

UAV internal communications system,

 

28

2-5

 

Notional UAV external communications system,

 

29

2-6

 

Human performance measures,

 

32

3-1

 

Variation of Reynolds number with altitude,

 

41

3-2

 

Maximum lift-to-drag ratio vs. Reynolds number showing influence of aspect ratio and laminar flow,

 

41

3-3

 

Unconventional designs with challenging configuration aerodynamics,

 

46

5-1

 

Propulsion system weight (engine plus fuel) as a percentage of aircraft takeoff gross weight,

 

60

5-2

 

Characteristics of propulsion and power systems for UAVs,

 

61

5-3

 

Typical power requirements for propeller-powered MAVs,

 

64

5-4

 

System mass vs. energy for several advanced, small energy systems,

 

65

5-5

 

Typical engine specifications for externally applied forces on takeoff, landing, and maneuvers,

 

68

6-1

 

Options for a prime power source for a range of average power levels and flight durations,

 

73

6-2

 

Schematic representation of overall aircraft power system,

 

73

6-3

 

Comparisons of specific power of space-based technologies with a broad range of power outputs,

 

76

6-4

 

Electrical power system and primary subsystems,

 

77

7-1

 

Integrated UAV control scenario,

 

83

7-2

 

Functional hierarchy of vehicle control systems,

 

84

7-3

 

Comparison of (a) traditional engineering design process with (b) virtual engineering design process,

 

88

Suggested Citation:"Front Matter." National Research Council. 2000. Uninhabited Air Vehicles: Enabling Science for Military Systems. Washington, DC: The National Academies Press. doi: 10.17226/9878.
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U.S. Air Force (USAF) planners have envisioned that uninhabited air vehicles (UAVs), working in concert with inhabited vehicles, will become an integral part of the future force structure. Current plans are based on the premise that UAVs have the potential to augment, or even replace, inhabited aircraft in a variety of missions. However, UAV technologies must be better understood before they will be accepted as an alternative to inhabited aircraft on the battlefield. The U.S. Air Force Office of Scientific Research (AFOSR) requested that the National Research Council, through the National Materials Advisory Board and the Aeronautics and Space Engineering Board, identify long-term research opportunities for supporting the development of technologies for UAVs. The objectives of the study were to identify technological developments that would improve the performance and reliability of “generation-after-next” UAVs at lower cost and to recommend areas of fundamental research in materials, structures, and aeronautical technologies. The study focused on innovations in technology that would “leapfrog” current technology development and would be ready for scaling-up in the post-2010 time frame (i.e., ready for use on aircraft by 2025).

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