cranfield college of aeronautics

309 Pages·2009·24.82 MB·English

LIBRARY
CRANFIELD UNIVERSITY
Spencer Woodford
The Minimisation Combat Aircraft Life Cycle Cost
of
through Conceptual Design Optimisation
CRANFIELD COLLEGE OF AERONAUTICS
Ph. D. THESIS
-It
UBFIARY
CRANFIELD UNIVERSITY
CRANFIELD COLLEGE OF AERONAUTICS
Ph. D. THESIS
1999
Spencer Woodford
The Minimisation Combat Aircraft Life Cycle Cost
of
through Conceptual Design Optimisation
Supervisor: Dr. Howard Smith
May 1999
ABSTRACT
In increase has been
to the
an effort cost-effectiveness of military equipment, a method
developed in designs
to
perform conceptual studies on combat aircraft, resulting of
for Life Cycle Cost (LCC). Consequently,
the
specified capability optimised minimum
design loop be being
the
cost can considered as closed, allowing automated production
data for different The
of a consistent set of cost and performance aircraft solutions.
design informed, design decisions, leading
thus to
engineer can make unbiased, a more
Defence budgets.
efficient use of shrinking
Because the to the be developed, 'deep
of vast scale which cost model could overheads'
included,
the the tool to the
are not restricting use of comparison of similar weapons
(combat design
systems aircraft), with a common set of objectives and performance
The design is based design
tool
constraints. aircraft conceptual on classical methods,
data. The
recently adapted and updated, and validated with existing aircraft engine
have been developed from detailed
thermodynamic
performance and sizing modules
LCC is different
the
models, whilst model an amalgamation and update of several
for different in life
the
methods, each written a phase system cycle.
The LCC described,
tool
aircraft synthesis models, opfimisation and algorithms are and
The
to
validation results are presented where possible. software cost model was used
design
the
generate a series of results, mimicking early stages of an aircraft selection
demonstration be
the trade-off that
procedure, and allowing a of various studies can
Results from discussed,
the
performed. selection process are presented and overall
drawn, for further Published data for
study conclusions arc and areas work suggested.
included in Appendices, detailed
the together
real aircraft and engines are with aircraft
data by
the
parameter and cost output generated model.
i
This is intentionally blank.
page
ii
ACKNOWLEDGEMENTS
The Author like to thank the the Cranfield College Aeronautics for
would staff of of
their help during the this in the in the Air
course of research, particular support staff
Vehicle Design Department, Denis Howe, John Fielding, Robert Jones, Alan
and
Morris, Pericles Pilidis, John Stollery, for in Special
their
and advice specialist areas.
Howard Smith, for his inspiration,
thanks to
encouragement, guidance, and support
through the this
whole of research programme.
Thanks
to:
also
Jack Mattingly, Seattle University, for for ONx
the the
of provision of source code and
OFFX improvement.
thermodynamic their
modelling routines, and advice on
Jack Vondrell, Wright Patterson Air Force Base, for his help in
of gathering and
data in Appendix B, from dimension
the the
validating engine contained which engine
developed.
and mass prediction methodology was
Wendy Kunc, the Office the US Assistant Secretary the Air Force (Financial
of of of
Management Comptroller), Lisa Johnson TASC, Inc., for
and and of confidential
USAF Visibility And Management Operation Support Cost
the
provision of of and
(VAMOSC) data USAF
and personnel numbers.
Tina Colarrosi, US Air Force Cost Analysis Agency, for her help
the
of on engine
drivers
production cost and prediction methods.
Philip Pugh, formerly MoD Directorate Project, Time, Cost Analysis, for his
of of and
drivers, discussion Life Cycle Costing.
thought-provoking
guidance on analysis, and of
Tony Gill Andy Clifford, the Defence Evaluation Research Agency, for their
and of and
feedback during
thorough the
review and research study.
Finally, Vikki, Family Friends, love has been
thanks to
and my and whose and support
'tricky bits'.
through the
unwavering
iii
This is intentionallY
blank.
page
iv
TA13LE CONTENTS
OF
ABSTRACT i
.................................................................................................................................. o ...... o ...........
ACKNOWLEDEGAIENTS iii
............................................................................................................... o ..............
TABLE OF CONTENTS
v
......................... o ........ o ....... o ......................................................................................
LIST OF FIGURES ix
.................................................................................. o .............. o .....................................
LISTOFTABLESo
xi
.................................................... ooo.. o.. o ........ oo ............. oo. oo .................................... o ..........
NOTATION
xiii
..................... o. 0 ...................... o .............. oo.. ooo ................ o ............ o ....... o. o ................. o. o ......... o .... oo.
INTRODUCTION I
............................................................................................................................
1.1 BACKGROUND DEFINITION 2
AND
......................................................................................................
1.2 RESEARCH JUSTIFICATION 4
..............................................................................................................
1.3 AiMS OBJECTIVES 8
AND
...................................................................................................................
LITERATURE SEARCH 11
..............................................................................................................
2.1 INTRODUCTION
12
.............................................................................................................................
2.2 PREVIOUS WORK 12
..........................................................................................................................
2.3 AREAS STUDY 15
OF
..........................................................................................................................
2.3.1 General Costing Literature 15
................................................................................................
2.3.2 A irfram 17
eL ayo ut
.................................................................................................................
2.3.3 Airframe Materials 18
.............................................................................................................
2.3.4 Propulsion Options 22
............................................................................................................
2.3.5 Avionics 28
..............................................................................................................................
2.3.6 Software 33
..............................................................................................................................
2.3.7 Reliability Maintainability 36
and
..........................................................................................
2.3.8 Other Data Sources 41
............................................................................................................
2.4 SUMMARY 44
....................................................................................................................................
OPTIMISATION PROCESSES AND TOOLS 45
............................................................................
3.1 INTRODUCTION 46
.............................................................................................................................
3.2 LIMITATIONS PITFALLS 47
AND
..........................................................................................................
3.2.1 Discontinuities 47
....................................................................................................................
3.2.2 Local Minima 49
.....................................................................................................................
3.3 DESCRIPTION OF RQPMIN 50
...........................................................................................................
3.3.1 Problem Formulation 50
.........................................................................................................
3.3.2 Variable Calegorisation 51
.....................................................................................................
3.3.3 Quantities Calculated by RQPMIN 51
....................................................................................
3.3.4 Convergence Criteria 52
.........................................................................................................
3.3.5 Inner Iterations 53
...................................................................................................................
3.3.6 Newton Iterations 53
...............................................................................................................
3.3.7 The Minimisation Step 54
........................................................................................................
3.3.8 The Feasibility Step 55
............................................................................................................
3.3.9 Other Functions 56
..................................................................................................................
3.3.10 Program Termination 56
.........................................................................................................
3.4 SUMMARY
57
....................................................................................................................................
PROGRAM STRUCTURE AND AIRFRAME DEFINITION 59
..................................................
4.1 DESCRIPTION AND OVERALL STRUCTURE 60
.....................................................................................
4.1.1 File Read Variable Initialisation 61
and
.................................................................................
4.1.2 Component Sizing 61
...............................................................................................................
4.1.3 Mass Estimation Volume Accounting 62
and
..........................................................................
V
Contents
4.1.4 Aerodynamic Estimation 62
....................................................................................................
4.1.5 Propulsion Modelling 62
.........................................................................................................
4.1.6 Performance Calculations 63
..................................................................................................
4.1.7 Life Cycle Cost Model 64
........................................................................................................
4.1.8 Aircraft Synthesis Output Routines 64
....................................................................................
4.1.9 Other Modules 65
....................................................................................................................
4.2 AIRFRAME COMPONENT SIZING 66
....................................................................................................
4.2.1 Aircraft Description Variables 67
...........................................................................................
4.2.2 Fuselage Sizing 68
..................................................................................................................
4.2.3 Wing Sizing 69
.........................................................................................................................
4.2.4 Sizing Correlations 71
.............................................................................................................
4.2.5 Empennage Sizing 72
..............................................................................................................
4.3 MASS ESTIMATION AND VOLUME ACCOUNTING 74
...........................................................................
4.3.1 Structural Mass Estimation 74
................................................................................................
4.3.2 Systems Mass Estimation 76
....................................................................................................
4.3.3 Mass Estimation Results 78
.....................................................................................................
4.3.4 Volume 79
accounting
.............................................................................................................
4.4 SUMMARY 82
....................................................................................................................................
5 AERODYNAMICS AND PROPULSION 83
....................................................................................
5.1 AERODYNAMIC MODELLING 84
....................................................................................................... ..
5.1.1 LiftModel 84
...........................................................................................................................
5.1.2 Angle-of-Attack Model 88
.......................................................................................................
5.1.3 Drag Model 91
.........................................................................................................................
5.2 ENGINE MODELLING ROUTINES 98
..................................................................................................
..
5.2.1 Code Modifications 101
..........................................................................................................
5.2.2 Engine Design Installation 103
and
........................................................................................
5.2.3 Off-Design Analysis & Engine Losses 105
. ..............................................................................
5.2.4 Engine Dimensions Mass Estimation III
and
........................................................................
5.3 SummARY
115
..................................................................................................................................
6 AIRCRAFT POINT AND MISSION PERFORMANCE
117
..........................................................
6.1 POINT PERFORMANCE CALCULATIONS
118
........................................................................................
6.1.1 Take-OffPerformance
119
......................................................................................................
6.1.2 Landing Performance
120
.......................................................................................................
6.1.3 Attained Turn Performance
121
..............................................................................................
6.1.4 Sustained Turn Performance
122
............................................................................................
6.1.5 MachlSpeed Performance
123
................................................................................................
61.6 Climb Performance
124
andAcceleration
..............................................................................
6.1.7 Specific Excess Power Constraint
127
....................................................................................
6.1.8 Calculation Altitude
127
ofMaximum
....................................................................................
6.2 MISSION PERFORMANCE CALCULATIONS
128
....................................................................................
6.2.1 Engine Start, Warm-up, Taxi,
129
etc
. ....................................................................................
6.2.2 Take-Off
129
...........................................................................................................................
62.3 Change in Energy-Height
130
.................................................................................................
6.2.4 Cruise
130
...............................................................................................................................
62.5 Manoeuvres
131
......................................................................................................................
6.2.6 Weapons Drop
132
..................................................................................................................
6.2.7 Loiter / Combat A ir Patrol 132
...............................................................................................
6.2.8 Landing
133
............................................................................................................................
6.2.9 Mission Termination
133
.........................................................................................................
62.10 Attained & Sustained Turn Data 133
......................................................................................
62.11 Post-Mission Calculations Constraint Evaluation 135
and
....................................................
6.3 SUM
MARY 137
..................................................................................................................................
vi
Contents
7 LIFE CYCLE COST MODEL
139
....................................................................................................
7.1 DESCRIPTION MODEL STRUCTURE
AND 140
......................................................................................
7.1.1 Research, Development, Test Evaluation (RDT&E) 140
and
..................................................
7.1.2 Production 140
........................................................................................................................
7.1.3 Operation Support (O&S) 140
and
.........................................................................................
7.1.4 Disposal 141
...........................................................................................................................
7.1.5 Structure Definition 141
..........................................................................................................
7.2 PARAMETER INITIALISATION
142
.......................................................................................................
7.2.1 Advanced Technology Factor 142
..... ....................................................................................
7.2.2 Number 142
ofPartners
..........................................................................................................
7.2.3 A MPR Mass 142
......................................................................................................................
7.2.4 Consumer Price Index 143
......................................................................................................
7.2.5 Labour Rates 143
....................................................................................................................
7.2.6 Advanced Materials Factor 144
..............................................................................................
7.2.7 Collaborative Factor 145
........................................................................................................
7.3 RES DEVELOPMENT, TEST, & EVALUATION
EARCI I, 146
...................................................................
7.3.1 Airframe Development 146
.....................................................................................................
7.3.2 Engine Development 148
.........................................................................................................
7.3.3 Avionics Development 149
......................................................................................................
7.3.4 Total Development 149
...........................................................................................................
7.4 PRODUCTION
150
..............................................................................................................................
7.4.1 Airframe Production 150
.........................................................................................................
7.4.2 Engine Production 151
............................................................................................................
7.4.3 Avionics Production 152
.........................................................................................................
7.4.4 Total Aircraft Production 152
.................................................................................................
7.4.5 Acquisition Unit Cost Recurring Flyaway Cost 152
and
.........................................................
7.5 GROUND SUPPORT EQUIPMENT INITIAL SPARES 153
AND
..................................................................
7.6 RELIABILITY MAINTAINA131LITY 154
AND
..........................................................................................
7.6.1 Arising Maintenance 155
........................................................................................................
7.6.2 Scheduled Maintenance 158
...................................................................................................
7.63 Total Maintenance Effort 159
.................................................................................................
7.7 OPERATION AND SUPPORT (O&S) 160
...............................................................................................
7.7.1 Operation Personnel 160
........................................................................................................
7.7.2 Support Personnel 161
............................................................................................................
7.7.3 Total Personnel Numbers Cost
162
and
.............................................................. ...................
7.7.4 Service Allowances, Personnel Support Training 162
and
.....................................................
7.7.5 Unit Level Consumption
163
.......................................................................... ........................
7.7.6 Contracts 165
...............................................................................................
..........................
7.7.7 Sustaining Support
166
......................................................... .................................................
7.7.8 Installation Support Funds 167
...................... ........................................................................
7.7.9 Total Operation Support Cost 167
and
...................................................................................
7.8 DISPOSAL 168
....................................................................................................................................
7.9 LIFE CYCLE COST 169
.......................................................................................................................
7.10 SU MMARY 170
.................................................................................................................................
GENERATION OF RESULTS
171
....................................................................................................
8.1 INTRODUCTION 172
...........................................................................................................................
8.1.1 Optimiser Convergence
172
....................................................................................................
8.1.2 Combat Validation
174
...........................................................................................................
8.2 PARAMETER DEFINITION
176
.............................................................................................................
8.2.1 Point Mission Performance Parameters
176
and
...................................................................
8.2.2 Engine Parameters
177
...........................................................................................................
8.2.3 Procurement Economic Parameters
179
and
..........................................................................
8.3 CONFIGURATION OPTIONS
180
..........................................................................................................
8.3.1 Single Engine Configurations
180
..........................................................................................
8.3.2 Twin Engine Configurations
182
............................................................................................
vii
Contents
8.3.3 Single Engine Twin Engine Comparison 184
vs.
....................................................................
8.3.4 Initial Configuration Selection 187
.........................................................................................
8.3.5 Internal Weapons Carriage 189
..............................................................................................
8.3.6 Effect Advanced Materials 191
of
...........................................................................................
8.3.7 Influence Objective Function 194
ofthe
.................................................................................
8.3.8 Final Configuration Selection 197
..........................................................................................
8.3.9 More Electric Aircraft Study 197
............................................................................................
8.4 SummARY 202
..................................................................................................................................
9 DISCUSSION AND CONCLUSIONS 203
........................................................................................
9.1 INTRODUCTION 204
...........................................................................................................................
9.2 FULFILMENT PROJECT AIMS 205
OF
...................................................................................................
9.2.1 Literature Review 205
.............................................................................................................
9.2.2 Optimisation 205
............
9.2.3 Program Structure Definition 206
andAirframe
....................................................................
9.2.4 Aerodynamics Propulsion 206
and
.........................................................................................
9.2.5 Aircraft Point Mission Performance 208
and
.........................................................................
9.2.6 Life Cycle Cost Model 209
......................................................................................................
9.2.7 Validation 211
.........................................................................................................................
9.2.8 Generation 211
ofResults
.......................................................................................................
9.3 AREAS FURTHER WORK 211
FOR
......................................................................................................
9.3.1 Reliability Maintainability Models 211
and
............................................................................
9.3.2 Operation Support Contract Costs 212
and
............................................................................
9.3.3 Improvement Model 212
ofLCC
.............................................................................................
9.3.4 Investigation Software LCC 213
ofA vionics and
...................................................................
9.3.5 Upgrade Engine Modelling Routines 213
the
of
.....................................................................
9.3.6 Aircraft 'Advanced Technologies 213
....................................................................................
9.3.7 Aircraft Synthesis Modifications 213
......................................................................................
9.4 CONCLUSIONS 214
.............................................................................................................................
REFERENCES 215
.......................................................................................................................................
APPENDIX A- AIRCRAFT DATA 223
.....................................................................................................
APPENDIX B- ENGINE DATA 225
..........................................................................................................
APPENDIX C- COMBAT OUTPUT DATA 227
......................................................................................
C. 1 EXAMPLE AIRCRAFT CONFIGURATIONS 227
......................................................................................
C. 2 SINGLE ENGINE CONFIGURATIONS 231
..............................................................................................
C. 3 TWIN ENGINE CONFIGURATIONS 247
.................................................................................................
CA ADVANCED MATERIALS STUDY
263
..................................................................................................
C. 5 MORE ELECTRIC AIRCRAFT STUDY
277
............................................................................................
viii