Computational Flight Dynamics

484 Pages·1998·17.327 MB·English

by  Malcolm J. Abzug

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Computational Flight Dynamics
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Texts Published in the AIAA Education Series
Computational Flight Dynamics Operations Research Analysis in
Malcolm J. Abzug 1998 Quality Test and Evaluation
Donald L. Giadrosich 1995
Space Vehicle Dynamics and Control
Bong Wie 1998 Radar and Laser Cross Section
Engineering
Introduction to Aircraft Flight David C. Jenn 1995
Dynamics
Louis V. Schmidt 1998 Introduction to the Control of
Dynamic Systems
Aerothermodynamics of Gas Turbine Frederick O. Smetana 1994
and Rocket Propulsion,
Third Edition Tailless Aircraft in Theory
97 Gordon C. Oates 1997 and Practice
6
61 Karl Nickel and Michael Wohlfahrt 1994
8
4. Advanced Dynamics
14/ Shuh-Jing Ying 1997 Mathematical Methods in Defense
5
0.2 Analyses,
DOI: 1 AIn tDroedsiugcnt iPoenr stop eAcetirvoenautics: J. SSe.c Pornzdem Eiedniiteiockni 1994
g | Steven A. Brandt, Randall J. Stiles,
a.or John J, Bertin, and Ray Whit ford 1997 Hypersonic Aerothermodynamics
aia John J. Bertin 1994
c. Introductory Aerodynamics and
ar
p:// Hydrodynamics of Wings and Bodies: Hypersonic Airbreathing
htt A Software-Based Approach Propulsion
2 | Frederick O. Smetana 1997 William H. Reiser and David T. Pratt 1994
1
0
2
9, An Introduction to Aircraft Practical Intake Aerodynamic
2
er Performance Design
b
m Mario Asselin 1997 E. L. Goldsmith and J. Seddon, 1993
e
pt Editors
e
n S Orbital Mechanics, Second Edition
y o V. A. Chobotov, Editor 1996 Acquisition of Defense Systems
versit Thermal Structures for Aerospace J. S. Przemieniecki, Editor 1993
ni
U Applications Dynamics of Atmospheric
ord Earl A. Thornton 1996 Re-Entry
anf Frank J. Regan and Satya M. 1993
y St Structural Loads Analysis for Anandakrishnan
d b Commercial Transport Aircraft:
de Theory and Practice Introduction to Dynamics and
a
nlo Ted L. Lomax 1996 Control of Flexible Structures
ow John L. Junkins and Youdan Kim 1993
D
Spacecraft Propulsion
Charles D. Brown 1996 Spacecraft Mission Design
Charles D. Brown 1992
Helicopter Flight Dynamics:
The Theory and Application Rotary Wing Structural Dynamics
of Flying Qualities and and Aeroelasticity
Simulation Modeling Richard L. Bielawa 1992
Gareth Padfield 1996
Aircraft Design: A Conceptual Approach,
Flying Qualities and Flight Testing Second Edition
of the Airplane Daniel P. Raymer 1992
Darrol Stinton 1996
Optimization of Observation and
Flight Performance of Aircraft Control Processes
S. K. Ojha 1995 Veniamin V. Malyshev, Mihkail N. 1992
Krasilshikov, and Valeri I. Karlov
Texts Published in the AIAA Education Series (continued)
Nonlinear Analysis of Shell Re-Entry Aerodynamics
Structures WilburL. Hankey 1988
Anthony N. Palazotto and 1992
Scott T. Dennis Aerothermodynamics of Gas Turbine
and Rocket Propulsion,
Orbital Mechanics Revised and Enlarged
Vladimir A. Chobotov, Editor 1991 Gordon C. Gates 1988
Critical Technologies for Advanced Classical Thermodynamics
National Defense George Emanuel 1988
Air Force Institute of Technology 1991
Radar Electronic Warfare
Defense Analyses Software August Golden Jr. 1988
7 J, S. Przemieniecki 1991
9
16 An Introduction to the Mathematics
86 Inlets for Supersonic Missiles and Methods of Astrodynamics
4.
4/ John J. Mahoney 1991 Richard H. Battin 1987
1
5
2
10. Space Vehicle Design Aircraft Engine Design
OI: Michael D. Griffin and 1991 Jack D. Mattingly, William H. 1987
D James R. French Reiser, and Daniel H. Daley
g |
or
a. Introduction to Mathematical Gasdynamics: Theory and
a
c.ai Methods in Defense Analyses Applications
p://ar J. S. Przemieniecki 1990 George Emanuel 1986
12 | htt JB. aSseidcd Hone licopter Aerodynamics 1990 CStormucptousrietes Materials for Aircraft
0
ber 29, 2 ATeircchrnaoftl oPgryo apnudls iDoens iSgynstems ABlraiann A C. .B Hakoesrk, iEnsd iatonrds 1986
m
e Gordon C. Gates, Editor 1989 Intake Aerodynamics
pt
Se J. Seddon and E. L. Goldsmith 1985
n Boundary Layers
o
ersity A. D. Young 1989 FSuurnvdiavmabeinlittayl As onfa Alyisricsr aafnt dC Domesbigant
v
ni Aircraft Design: A Conceptual Robert E. Ball 1985
U
d Approach
nfor Daniel R Raymer 1989 Aerothermodynamics of Aircraft
Sta Engine Components
by Gust Loads on Aircraft: Concepts and Gordon C. Gates, Editor 1985
d Applications
e
d
oa Frederic M. Hoblit 1988 Aerothermodynamics of Gas Turbine
wnl and Rocket Propulsion
Do Aircraft Landing Gear Design: Gordon C. Gates 1984
Principles and Practices
Norman S. Currey 1988 Re-Entry Vehicle Dynamics
Frank J. Regan 1984
Mechanical Reliability: Theory, Models
and Applications
B. S. Dhillon 1988
Published by
American Institute of Aeronautics
and Astronautics, Inc.
Reston, Virginia
Computational Flight Dynamics
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61 Malcolm J. Abzug
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Do EDUCATION SERIES
J. S. Przemieniecki
Series Editor-in-Chief
Air Force Institute of Technology
Wright-Patterson Air Force Base, Ohio
Published by
American Institute of Aeronautics and Astronautics, Inc.
1801 Alexander Bell Drive, Reston, VA 20191
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2 | htt MS-DOS and Windows are registered trademarks of the Microsoft Corporation
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er American Institute of Aeronautics and Astronautics, Inc., Reston, Virginia
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o Library of Congress Cataloging-in-Publication Data
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versit Abzug, Malcolm J.
Uni Computational flight dynamics / Malcolm J. Abzug.
d p. cm.—(AIAA education series)
nfor Includes bibliographical references and index.
Sta ISBN 1-56347-259-7 (alk. paper)
by 1. Aerodynamics—Computer programs. 2. Aerodynamics—Computer
ed simulation. I. Title. II. Series.
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a TL573.A14 1998 629.132'3'00113—dc21 98-12761
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o Copyright © 1998 by the American Institute of Aeronautics and Astronautics, Inc.
D
All rights reserved. Printed in the United States of America. No part of this publica-
tion may be reproduced, distributed, or transmitted, in any form or by any means, or
stored in a database or retrieval system, without the prior written permission of the
publisher.
Data and information appearing in this book are for informational purposes only.
AIAA is not responsible for any injury or damage from use or reliance, nor does
AIAA warrant that use or reliance will be free from privately owned rights.
Foreword
Computational Flight Dynamics by Malcolm J. Abzug is a text with com-
puter programs for use with the design and analysis of aircraft dynamic
stability, control, and flight performance. Based on his extensive practical
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69 experience with the aerospace industry, the author compiled and developed
1
6
8 five computer programs provided on a separate diskette. The five programs
4.
4/ are 1) Program LOCUS: s-plane Root Locus, 2) Program ZPLANE: z-plane
1
5
2 Root Locus, 3) Program FLIGHT: Transient Response, 4) Program PER-
0.
OI: 1 FORM: Flight Path Calculation, and 5) Program COVAR: Covariance
D Propagation. These programs provide an excellent opportunity for students
g | and aerospace engineers to obtain hands-on experience with the computa-
or
a. tional methods used by the aerospace industry.
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c. The text is effectively a user's manual for the study of uncontrolled
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htt control systems. Two of the programs (FLIGHT and LOCUS) were actually
12 | used for the flight-control system designs for two production unmanned air
0
9, 2 vehicles. Throughout the text the author provides enough background ma-
er 2 terial and necessary mathematical principles for the user to understand how
mb these programs can be modified. The concept of a user's manual/textbook is
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pt new for the Education Series; however, because of its great educational
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n value for students and industry professionals, it can be expected that more
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y texts of this type will be appearing in the future.
ersit The Education Series of textbooks and monographs, published by the
v
Uni American Institute of Aeronautics and Astronautics, embraces broadly the
ord theory and application of different disciplines in aeronautics and astronau-
anf tics, including aerospace design practice. The series includes books on de-
St
y fense science, engineering, and management. The complete list of textbooks
b
d published in the series (over 50 titles) can be found on the end pages of this
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d
oa volume. The series provides teaching texts as well as reference materials for
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J. S. Przemieniecki
Editor-in-Chief
AIAA Education Series
Table of
Contents
Preface......................................................... ix
1. Airframe and Atmosphere Modeling............................ 1
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69 1.1 Axes Systems, Attitude Coordinates......................... 1
1
6
4.8 1.2 Rigid-Body Equations of Motion, Body Axes................. 9
14/ 1.3 Rigid-Body Equations of Motion, Mixed Body/Stability/
5
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0. Wind Axes.......................................... 12
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D
g | 1.5 Perturbation Equations................................... 18
or 1.6 Angles of Attack and Sideslip ............................. 21
a.
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c.
p://ar 1.8 Aerodynamic Reference and Body Axis Transformations ..... 25
htt 1.9 Primed Derivatives ...................................... 27
2 | 1.10 Origin of Body Axes Not at the Mass Center ................ 28
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9, 2 1.11 Standard Atmosphere Models............................. 29
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er 1.12 Winds, Gusts, Shears, Downbursts, Vortices, and Turbulence.... 29
b
m 1.13 Ground Effect........................................... 34
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niv 1.17 Buoyancy and Apparent Mass............................. 44
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d 2.1 System Matrix Models: Continuous Controller............... 49
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2.4 Actuators............................................... 74
2.5 Gimbaled Devices ....................................... 78
2.6 Limiters................................................ 82
2.7 Shaping Filters .......................................... 83
2.8 Accelerometers, Other Flight Instruments................... 89
2.9 Transport Delays ........................................ 93
2.10 Loop Numbering System ................................. 95
vii
3. Program LOCUS: s-Plane Root Locus ......................... 99
3.1 Root Locus Method...................................... 99
3.2 Fundamental Equations .................................. 99
3.3 Poles, Zeros, Asymptotes................................. 100
3.4 Multiple-Loop Root Locus............................... 100
3.5 Gain Intervals.......................................... 101
3.6 Typical Design Criteria .................................. 102
3.7 Root Finders........................................... 103
3.8 Aircraft-Related Preprocessing........................... 104
7 3.9 Automatic Trimming .................................... 104
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1 3.10 Check Solutions ........................................ 106
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4. 3.11 Line-Printer Plotting .................................... 108
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5 3.12 Flight Condition and Inner Loop Gain Iteration ............ 110
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DOI: 3.14 Run File............................................... 115
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12 | 4. Program ZPLANE: z-Plane Root Locus....................... 131
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9, 2 4.1 Relationship to s-Plane Root Locus ....................... 131
2
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niv 4.7 Run File............................................... 137
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5.2 Integration Algorithms .................................. 151
5.3 Time and Print Interval Selection ......................... 153
5.4 Aircraft-Related Preprocessing........................... 155
5.5 Initialization and Automatic Trimming..................... 155
5.6 Calculated Outputs ..................................... 156
5.7 Programmed Inputs..................................... 157
vili
5.8 Interpolation........................................... 159
5.9 State-Variable Assignments .............................. 160
5.10 Line-Printer Tables and Plots............................. 160
5.11 Statistical Analysis ...................................... 164
5.12 Control System Models.................................. 165
5.13 FLIGHT Program Modules .............................. 167
5.14 Run File............................................... 171
5.15 Output File ............................................ 177
5.16 FLIGHT in Real-Time Applications....................... 192
7 5.17 FLIGHT Operations.................................... 193
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4/ 6. Program PERFORM: Flight-Path Calculation.................. 197
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0.2 6.1 Uses of Flight-Path Calculation........................... 197
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OI: 6.2 Programmed Inputs..................................... 198
g | D 6.3 State-Variable Assignments .............................. 198
or 6.4 Line-Printer Tables and Plots............................. 199
a.
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c.
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http:// 6.7 Output File ............................................ 203
2 | 6.8 Specialized Closed Loops for Flight-Path Generation........ 212
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7.11 Output File ............................................ 230
7.12 COVAR Operations .................................... 234
8. Utility Subroutines.......................................... 235
8.1 Cross Reference of Programs and Subroutines.............. 235
8.2 Subroutine Validation Programs .......................... 235
ix