INCOSE Systems Engineering Handbook Fifth Edition PDF

This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This PDF copy of the SE Handbook, Fi h Edi...

This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. SYSTEMS ENGINEERING HANDBOOK This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. SYSTEMS ENGINEERING HANDBOOK A GUIDE FOR SYSTEM LIFE CYCLE PROCESSES AND ACTIVITIES FIFTH EDITION INCOSE-TP-2003–002-05 2023 Prepared by: International Council on Systems Engineering (INCOSE) 7670 Opportunity Rd, Suite 220 San Diego, CA, USA 92111-2222 Compiled and Edited by: DAVID D. WALDEN, ESEP — EDITOR-IN-CHIEF — AMERICAS SECTOR THOMAS M. SHORTELL, CSEP — DEPUTY EDITOR-IN-CHIEF — AMERICAS SECTOR GARRY J. ROEDLER, ESEP — EDITOR — AMERICAS SECTOR BERNARDO A. DELICADO, ESEP — EDITOR — EMEA SECTOR ODILE MORNAS, ESEP — EDITOR — EMEA SECTOR YIP YEW-SENG, CSEP — EDITOR — ASIA OCEANIA SECTOR DAVID ENDLER, ESEP — EDITOR — EMEA SECTOR This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This edition first published 2023 © 2023 John Wiley & Sons Ltd. Edition History Fourth edition, 2015 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by law. Advice on how to obtain permission to reuse material from this title is available at http://www.wiley.com/go/permissions. The right of INCOSE; David Walden to be identified as the editorial material in this work has been asserted in accordance with law. Registered Offices John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK For details of our global editorial offices, customer services, and more information about Wiley products visit us at www.wiley.com. Wiley also publishes its books in a variety of electronic formats and by print-on-demand. Some content that appears in standard print versions of this book may not be available in other formats. Trademarks: Wiley and the Wiley logo are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates in the United States and other countries and may not be used without written permission. All other trademarks are the property of their respective owners. John Wiley & Sons, Inc. is not associated with any product or vendor mentioned in this book. Limit of Liability/Disclaimer of Warranty While the publisher and authors have used their best efforts in preparing this work, they make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives, written sales materials or promotional statements for this work. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategies contained herein may not be suitable for your situation. You should consult with a specialist where appropriate. The fact that an organization, website, or product is referred to in this work as a citation and/or potential source of further information does not mean that the publisher and authors endorse the information or services the organization, website, or product may provide or recommendations it may make. Further, readers should be aware that websites listed in this work may have changed or disappeared between when this work was written and when it is read. Neither the publisher nor authors shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. Library of Congress Cataloging-in-Publication Data Names: Walden, David D., editor. | International Council on Systems Engineering, editor. Title: INCOSE systems engineering handbook / edited by INCOSE, David Walden. Description: Fifth edition. | Hoboken, NJ : John Wiley & Sons Ltd., | Includes index. Identifiers: LCCN 2023022915 | ISBN 9781119814290 (paperback) | ISBN 9781119814306 (adobe pdf) | ISBN 9781119814313 (epub) Subjects: LCSH: Systems engineering--Handbooks, manuals, etc. | Product life cycle--Handbooks, manuals, etc. Classification: LCC TA168.I444 2023 | DDC 620/.0042--dc23/eng/20230525 LC record available at https://lccn.loc.gov/2023022915 Cover Design: Wiley Cover Images: © DANNY HU/Getty Images, © Zero Creatives/Getty Images, © Stebenkov Roman/Shutterstock, © Phonlamai Photo/ Shutterstock, © MNBB Studio/Shutterstock, © Titima Ongkantong/Shutterstock Set in 10/12pt TimesLTStd by Integra Software Services Pvt. Ltd., Pondicherry, India This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. CONTENTS INCOSE Notices ix History of Changes xi List of Figures xiii List of Tables xvii Preface xix How to Use This Handbook xxi 1 Systems Engineering Introduction 1 1.1 What Is Systems Engineering? 1 1.2 Why Is Systems Engineering Important? 4 1.3 Systems Concepts 8 1.3.1 System Boundary and the System of Interest (SoI) 8 1.3.2 Emergence 9 1.3.3 Interfacing Systems, Interoperating Systems, and Enabling Systems 10 1.3.4 System Innovation Ecosystem 11 1.3.5 The Hierarchy within a System 12 1.3.6 Systems States and Modes 14 1.3.7 Complexity 15 1.4 Systems Engineering Foundations 15 1.4.1 Uncertainty 15 1.4.2 Cognitive Bias 17 1.4.3 Systems Engineering Principles 17 1.4.4 Systems Engineering Heuristics 20 1.5 System Science and Systems Thinking 21 v This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. vi Contents 2 System Life Cycle Concepts, Models, and Processes 25 2.1 Life Cycle Terms and Concepts 25 2.1.1 Life Cycle Characteristics 25 2.1.2 Typical Life Cycle Stages 26 2.1.3 Decision Gates 29 2.1.4 Technical Reviews and Audits 31 2.2 Life Cycle Model Approaches 33 2.2.1 Sequential Methods 35 2.2.2 Incremental Methods 36 2.2.3 Evolutionary Methods 38 2.3 System Life Cycle Processes 39 2.3.1 Introduction to the System Life Cycle Processes 39 2.3.1.1 Format and Conventions 40 2.3.1.2 Concurrency, Iteration, and Recursion 42 2.3.2 Agreement Processes 44 2.3.2.1 Acquisition Process 45 2.3.2.2 Supply Process 48 2.3.3 Organizational Project-Enabling Processes 50 2.3.3.1 Life Cycle Model Management Process 51 2.3.3.2 Infrastructure Management Process 54 2.3.3.3 Portfolio Management Process 57 2.3.3.4 Human Resource Management Process 60 2.3.3.5 Quality Management Process 63 2.3.3.6 Knowledge Management Process 67 2.3.4 Technical Management Processes 70 2.3.4.1 Project Planning Process 70 2.3.4.2 Project Assessment and Control Process 75 2.3.4.3 Decision Management Process 78 2.3.4.4 Risk Management Process 81 2.3.4.5 Configuration Management Process 87 2.3.4.6 Information Management Process 91 2.3.4.7 Measurement Process 93 2.3.4.8 Quality Assurance Process 98 2.3.5 Technical Processes 101 2.3.5.1 Business or Mission Analysis Process 103 2.3.5.2 Stakeholder Needs and Requirements Definition Process 107 2.3.5.3 System Requirements Definition Process 112 2.3.5.4 System Architecture Definition Process 118 2.3.5.5 Design Definition Process 124 2.3.5.6 System Analysis Process 129 2.3.5.7 Implementation Process 132 2.3.5.8 Integration Process 134 2.3.5.9 Verification Process 138 2.3.5.10 Transition Process 143 2.3.5.11 Validation Process 146 2.3.5.12 Operation Process 152 2.3.5.13 Maintenance Process 154 2.3.5.14 Disposal Process 156 This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge.  Contents vii 3 Life Cycle Analyses and Methods 159 3.1 Quality Characteristics and Approaches 159 3.1.1 Introduction to Quality Characteristics 159 3.1.2 Affordability Analysis 160 3.1.3 Agility Engineering 165 3.1.4 Human Systems Integration 168 3.1.5 Interoperability Analysis 171 3.1.6 Logistics Engineering 172 3.1.7 Manufacturability/Producibility Analysis 175 3.1.8 Reliability, Availability, Maintainability Engineering 176 3.1.9 Resilience Engineering 180 3.1.10 Sustainability Engineering 184 3.1.11 System Safety Engineering 185 3.1.12 System Security Engineering 190 3.1.13 Loss-Driven Systems Engineering 191 3.2 Systems Engineering Analyses and Methods 192 3.2.1 Modeling, Analysis, and Simulation 192 3.2.2 Prototyping 200 3.2.3 Traceability 201 3.2.4 Interface Management 202 3.2.5 Architecture Frameworks 206 3.2.6 Patterns 208 3.2.7 Design Thinking 212 3.2.8 Biomimicry 213 4 Tailoring and Application Considerations 215 4.1 Tailoring Considerations 215 4.2 SE Methodology/Approach Considerations 219 4.2.1 Model-Based SE 219 4.2.2 Agile Systems Engineering 221 4.2.3 Lean Systems Engineering 224 4.2.4 Product Line Engineering (PLE) 226 4.3 System Types Considerations 229 4.3.1 Greenfield/Clean Sheet Systems 229 4.3.2 Brownfield/Legacy Systems 230 4.3.3 Commercial-off-the-Shelf (COTS)-Based Systems 231 4.3.4 Software-Intensive Systems 232 4.3.5 Cyber-Physical Systems (CPS) 233 4.3.6 Systems of Systems (SoS) 235 4.3.7 Internet of Things (IoT)/Big Data-Driven Systems 238 4.3.8 Service Systems 239 4.3.9 Enterprise Systems 241 4.4 Application of Systems Engineering for Specific Product Sector or Domain Application 244 4.4.1 Automotive Systems 245 4.4.2 Biomedical and Healthcare Systems 248 4.4.3 Commercial Aerospace Systems 249 4.4.4 Defense Systems 250 This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. viii Contents 4.4.5 Infrastructure Systems 251 4.4.6 Oil and Gas Systems 253 4.4.7 Power & Energy Systems 254 4.4.8 Space Systems 255 4.4.9 Telecommunication Systems 257 4.4.10 Transportation Systems 258 5 Systems Engineering in Practice 261 5.1 Systems Engineering Competencies 261 5.1.1 Difference between Hard and Soft Skills 262 5.1.2 System Engineering Professional Competencies 263 5.1.3 Technical Leadership 263 5.1.4 Ethics 264 5.2 Diversity, Equity, and Inclusion 265 5.3 Systems Engineering Relationships to Other Disciplines 266 5.3.1 SE and Software Engineering (SWE) 266 5.3.2 SE and Hardware Engineering (HWE) 267 5.3.3 SE and Project Management (PM) 268 5.3.4 SE and Industrial Engineering (IE) 270 5.3.5 SE and Operations Research (OR) 271 5.4 Digital Engineering 273 5.5 Systems Engineering Transformation 274 5.6 Future of SE 275 6 Case Studies 277 6.1 Case 1: Radiation Therapy—the Therac-25 277 6.2 Case 2: Joining Two Countries—the Øresund Bridge 278 6.3 Case 3: Cybersecurity Considerations in Systems Engineering—the Stuxnet Attack on a Cyber-Physical System 280 6.4 Case 4: Design for Maintainability—Incubators 282 6.5 Case 5: Artificial Intelligence in Systems Engineering—Autonomous Vehicles 283 6.6 Other Case Studies 285 Appendix A: References 287 Appendix B: Acronyms 305 Appendix C: Terms and Definitions 311 Appendix D: N2 Diagram of Systems Engineering Processes 317 Appendix E: Input/Output Descriptions 321 Appendix F: Acknowledgments 335 Appendix G: Comment Form 337 Index 339 This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. INCOSE NOTICES This International Council on Systems Engineering (INCOSE) Technical Product was prepared by the INCOSE Systems Engineering Handbook Team. It is approved by the INCOSE Technical Operations Leadership for release as an INCOSE Technical Product. Copyright ©2023 by INCOSE, subject to the following restrictions: Author Use: Authors have full rights to use their contributions in a totally unfettered way with credit to the INCOSE technical source, except as noted in the following text. Abstraction is permitted with credit to the source. INCOSE Use: Permission to reproduce and use this document or parts thereof by members of INCOSE and to pre- pare derivative works from this document for INCOSE use is granted, with attribution to INCOSE and the original author(s) where practical, provided this copyright notice is included with all reproductions and derivative works. Content from ISO/IEC/IEEE 15288 and ISO/IEC TR 24748‐1 is used by permission and is not to be reproduced other than as part of this total document. External Use: This document may not be shared or distributed to any non‐INCOSE third party. Requests for per- mission to reproduce this document in whole or in part, or to prepare derivative works of this document for external and/or commercial use should be addressed to the INCOSE Central Office, 7670 Opportunity Road, Suite 220, San Diego, CA 92111‐2222, USA. Electronic Version Use: Any electronic version of this document is to be used for personal, professional use only and is not to be placed on a non‐INCOSE sponsored server for general use. Any additional use of these materials must have written approval from the INCOSE Central. General Citation Guidelines: References to this handbook should be formatted as follows, with appropriate adjust- ments for formally recognized styles: INCOSE SEH (2023). Systems Engineering Handbook: A Guide for System Life Cycle Process and Activities (5th ed.). D. D. Walden, T. M. Shortell, G. J. Roedler, B. A. Delicado, O. Mornas, Yip Y. S., and D. Endler (Eds.). San Diego, CA: International Council on Systems Engineering. Published by John Wiley & Sons, Inc. ix This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. HISTORY OF CHANGES Revision Revision date Change description and rationale Original Jun 1994 Draft Systems Engineering Handbook (SEH) created by INCOSE members from several defense/aerospace companies—including Lockheed, TRW, Northrop Grumman, Ford Aerospace, and the Center for Systems Management—for INCOSE review. 1.0 Jan 1998 Initial SEH release approved to update and broaden coverage of SE process. Included broad participation of INCOSE members as authors. Based on Interim Standards EIA 632 and IEEE 1220. 2.0 Jul 2000 Expanded coverage on several topics, such as functional analysis. This version was the basis for the development of the Certified Systems Engineering Professional (CSEP) exam. 2.0A Jun 2004 Reduced page count of SEH v2 by 25% and reduced the US DoD‐centric material wherever possible. This version was the basis for the first publicly offered CSEP exam. 3.0 Jun 2006 Significant revision based on ISO/IEC 15288:2002. The intent was to create a country‐ and domain-neutral handbook. Significantly reduced the page count, with elaboration to be provided in appendices posted online in the INCOSE Product Asset Library (IPAL). 3.1 Aug 2007 Added detail that was not included in SEH v3, mainly in new appendices. This version was the basis for the updated CSEP exam. 3.2 Jan 2010 Updated version based on ISO/IEC/IEEE 15288:2008. Significant restructuring of the handbook to consolidate related topics. 3.2.1 Jan 2011 Clarified definition material, architectural frameworks, concept of operations references, risk references, and editorial corrections based on ISO/IEC review. 3.2.2 Oct 2011 Correction of errata introduced by revision 3.2.1. 4.0 Jul 2015 Significant revision based on ISO/IEC/IEEE 15288:2015, inputs from the relevant INCOSE working groups (WGs), and to be consistent with the Guide to the Systems Engineering Body of Knowledge (SEBoK). 5.0 Jul 2023 Significant revision based on ISO/IEC/IEEE 15288:2023 and inputs from the relevant INCOSE working groups (WGs). Significant restructuring of the handbook based inputs from INCOSE stakeholders. xi This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. LIST OF FIGURES 1.1 Acceleration of design to market life cycle has prompted development of more automated design methods and tools 1.2  Cost and schedule overruns correlated with SE effort 1.3  Project performance versus SE capability 1.4  Life cycle costs and defect costs against time 1.5  Emergence 1.6  System innovation ecosystem pattern 1.7  Hierarchy within a system 1.8  An architectural framework for the evolving the SE discipline 2.1  System life cycle stages 2.2  Generic life cycle stages compared to other life cycle viewpoints 2.3  Criteria for decision gates 2.4  Relationship between technical reviews and audits and the technical baselines 2.5  Concepts for the three life cycle model approaches 2.6  The SE Vee model 2.7  The Incremental Commitment Spiral Model (ICSM) 2.8  DevSecOps 2.9  Asynchronous iterations and increments across agile mixed discipline engineering 2.10  System life cycle processes per ISO/IEC/IEEE 15288 2.11  Sample IPO diagram for SE processes 2.12  Concurrency, iteration, and recursion 2.13  IPO diagram for the Acquisition process 2.14  IPO diagram for the Supply process 2.15  IPO diagram for Life Cycle Model Management process 2.16  IPO diagram for Infrastructure Management process 2.17  IPO diagram for Portfolio Management process 2.18  Requirements across the portfolio, program, and project domains 2.19  IPO diagram for Human Resource Management process xiii This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. xiv List of Figures 2.20  IPO diagram for the Quality Management process 2.21  QM Values and Skills Integration 2.22  IPO diagram for Knowledge Management process 2.23  IPO diagram for Project Planning process 2.24  The breakdown structures 2.25  IPO diagram for Project Assessment and Control process 2.26  IPO diagram for the Decision Management process 2.27  IPO diagram for Risk Management process 2.28  Level of risk depends upon both likelihood and consequence 2.29  Intelligent management of risks and opportunities 2.30  Typical relationship among the risk categories 2.31  IPO diagram for Configuration Management process 2.32  IPO diagram for Information Management process 2.33  IPO diagram for Measurement process Integration of Measurement, Risk Management, and Decision Management processes 2.34  2.35  Relationship of product‐oriented measures 2.36  TPM monitoring IPO diagram for the Quality Assurance process 2.37  2.38  Technical Processes in context 2.39  IPO diagram for Business or Mission Analysis process 2.40  IPO diagram for Stakeholder Needs and Requirements Definition process 2.41  IPO diagram for System Requirements Definition process IPO diagram for System Architecture Definition process 2.42  2.43  Core architecture processes 2.44  IPO diagram for Design Definition process Taxonomy of system analysis dimensions 2.45  2.46  IPO diagram for System Analysis process 2.47  IPO diagram for Implementation process IPO diagram for Integration process 2.48  IPO diagram for Verification process 2.49  2.50  Verification per level 2.51  IPO diagram for Transition process IPO diagram for Validation process 2.52  2.53  Validation per level 2.54  IPO diagram for Operation process 2.55  IPO diagram for Maintenance process 2.56  IPO diagram for Disposal process 3.1  Quality characteristic approaches across the life cycle 3.2  System operational effectiveness 3.3  Cost versus performance 3.4  Life cycle cost elements 3.5  HSI technology, organization, people within an environment 3.6  Interaction between system, environment, operating conditions, and failure modes and failure mechanisms 3.7  Timewise values of notional resilience scenario parameters 3.8  Schematic view of a generic MA&S process 3.9  System development with early, iterative V&V and integration, via modeling, analysis, and simulation 3.10  Illustrative model taxonomy (non-exhaustive) 3.11  Model-based integration across multiple disciplines using a hub-and-spokes pattern 3.12  Multidisciplinary MA&S coordination along the life cycle 3.13  Sample N-squared diagram This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge.  List of Figures xv 3.14  Sample coupling matrix showing: (a) Initial arrangement of aggregates; (b) final arrangement after reorganization 3.15  Unified Architecture Method 3.16  Enterprise and product frameworks 3.17  S*Pattern class hierarchy 3.18  Examples of natural systems applications and biomimicry 4.1  Tailoring requires balance between risk and process 4.2  IPO diagram for Tailoring process 4.3  SE life cycle spectrum 4.4  Agile SE life cycle model 4.5  Feature-based PLE factory 4.6  Schematic diagram of the operation of a Cyber-Physical System 4.7  The relationship between Cyber-Physical Systems (CPS), Systems of Systems (SoSs), and an Internet of Things (IoT) 4.8  Example of the systems and systems of systems within a transport system of systems 4.9  Service system conceptual framework 4.10  Organizations manage resources to create enterprise value 4.11  Individual competence leads to organizational, system, and operational capability 4.12  Enterprise state changes through work process activities 5.1  The “T-shaped” SE practitioner. From Delicado, et al. (2018). Used with permission. All other rights reserved. 262 5.2  Technical leadership is the intersection of technical expertise and leadership skills 5.3  Categorized dimensions of diversity 5.4  The intersection between PM and SE 5.5  IE and SE relationships Timeline of vehicle impact 6.1  D.1 Input/output relationships between the various SE processes This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. LIST OF TABLES 1.1 SE standards and guides 1.2 SE return on investment 1.3 Examples for systems interacting with the SoI 1.4 Sources of system uncertainty 1.5 Common cognitive biases 1.6 SE principles and subprinciples 2.1 Representative technical reviews and audits 2.2 Life cycle model approach characteristics 2.3 Eight Attributes of a Quality Management Culture 2.4 Partial list of decision situations (opportunities) throughout the life cycle 2.5 Measurement benefits 2.6 Measurement references for specific measurement focuses 2.7 Requirement statement characteristics 2.8 Requirement set characteristics 2.9 Requirement attributes 3.1 Quality Characteristic approaches 3.2 HSI perspective descriptions 3.3 Resilience considerations 3.4 Implementation process breakout 4.1 Considerations of greenfield and brownfield development efforts 4.2 Considerations for COTS-based development efforts 4.3 SoS types 4.4 Impact of SoS considerations on the SE processes 4.5 Comparison of automotive, aerospace/defense, and consumer electronics domains 4.6 Representative organizations and standards in the automotive industry 4.7 Infrastructure and SE definition correlation 5.1 Differences between the hard skills and soft skills 5.2 Technical leadership model xvii This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. PREFACE The objective of the International Council on Systems Engineering (INCOSE) Systems Engineering Handbook (SEH) is to describe key Systems Engineering (SE) process activities. The intended audience is the SE practitioner. When the term “SE practitioner” is used in this handbook, it includes the new SE practitioner, a product engineer, an engi- neer in another discipline who needs to perform SE, or an experienced SE practitioner who needs a convenient reference. The descriptions in this handbook show what each SE process activity entails, in the context of designing for required performance and life cycle considerations. On some projects, a given activity may be performed very informally; on other projects, it may be performed very formally, with interim products under formal configura- tion control. This document is not intended to advocate any level of formality as necessary or appropriate in all situations. The appropriate degree of formality in the execution of any SE process activity is determined by the following: The need for communication of what is being done (across members of a project team, across organizations, or over time to support future activities) The level of uncertainty The degree of complexity The consequences to human welfare On smaller projects, where the span of required communications is small (few people and short project life cycle) and the cost of rework is low, SE activities can be conducted very informally and thus at low cost. On larger projects, where the span of required communications is large (many teams that may span multiple geographic locations and organiza- tions and long project life cycle) and the cost of failure or rework is high, increased formality can significantly help in achieving project opportunities and in mitigating project risk. In a project environment, work necessary to accomplish project objectives is considered “in scope”; all other work is considered “out of scope.” On every project, “thinking” is always “in scope.” Thoughtful tailoring and intelligent application of the SE processes described in this handbook are essential to achieve the proper balance between the risk of missing project technical and business objectives on the one hand and process paralysis on the other hand. Part IV provides tailoring and application guidance to help achieve that balance. xix This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. xx Preface APPROVED FOR THE INCOSE SEH FIFTH EDITION: Christopher D. Hoffman, CSEP, INCOSE Technical Director, January 2021-January 2023 Olivier Dessoude, INCOSE Technical Director, January 2023-January 2025 Theodore J. Ferrell, INCOSE Assistant Director, Technical Review, January 2021-January 2023 Krystal Porter, INCOSE Assistant Director, Technical Review, January 2023-January 2025 Lori F. Zipes, ESEP, INCOSE Assistant Director, Technical Information, January 2022-January 2024 Tony Williams, ESEP, INCOSE Assistant Director, Product Champion, January 2022-January 2025 This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. HOW TO USE THIS HANDBOOK PURPOSE This handbook defines the “state-of-the-good-practice” for the discipline of Systems Engineering (SE) and provides an authoritative reference to understand the SE discipline in terms of content and practice. APPLICATION This handbook is consistent with ISO/IEC/IEEE 15288 (2023), Systems and software engineering—System life cycle processes, hereafter referred to as ISO/IEC/IEEE 15288, to ensure its usefulness across a wide range of application domains for engineered systems and products, as well as services. ISO/IEC/IEEE 15288 is an international standard that provides system life cycle process outcomes, activities, and tasks, whereas this handbook further elaborates on the activities and practices necessary to execute the processes. This handbook is also consistent with the Guide to the Systems Engineering Body of Knowledge, hereafter referred to as the SEBoK (2023), to the extent practicable. In many places, this handbook points readers to the SEBoK for more detailed coverage of the related topics, including a current and vetted set of references. The SEBoK also includes cov- erage of “state-of-the-art” in SE. For organizations that do not follow the principles of ISO/IEC/IEEE 15288 or the SEBoK to specify their life cycle processes, this handbook can serve as a reference to practices and methods that have proven beneficial to the SE community at large and that can add significant value in new domains, if appropriately selected, tailored, and applied. Part IV provides top-level guidance on the application of SE in selected product sectors and domains. Before applying this handbook in a given organization or on a given project, it is recommended that the tailoring guidelines in Part IV be used to remove conflicts with existing policies, procedures, and standards already in use within an organization. Not every process will apply universally. Careful selection from the material is recommended. Reliance on process over progress will not deliver a system. Processes and activities in this handbook do not supersede any international, national, or local laws or regulations. USAGE This handbook was developed to support the users and use cases shown in Table 0.1. Primary users are those who will use the handbook directly. Secondary users are those who will typically use the handbook with assistance from SE practitioners. Other users and use cases are possible. xxi This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. xxii How to Use This Handbook TABLE 0.1 Handbook users and use cases User Type Use cases Seasoned SE Practitioner. Those who need to Primary Adapt or refer to handbook to suit individual applicability reinforce, refresh, and renew their SE Explore good practices knowledge Identify blind spots or gaps by providing a good checklist to ensure necessary coverage References to other sources for more in-depth understanding Novice SE Practitioner: Those who need to Primary Support structured, coherent, and comprehensive learning start using SE Understand the scope (breadth and depth) of systems thinking and SE practices INCOSE Certification: Systems Engineering Primary Define body of knowledge for SEP certification Professional (SEP) certifiers and those Form the basis of the SEP examination being certified SE Educators: Those who develop and teach Primary Support structured, coherent, and comprehensive learning SE courses, including universities and Suggest relevant SE topics to trainers for their course content trainers Serve as a supplemental teaching aid SE Tool Providers/Vendors: Those who Primary Suggest tools, methods, or other solutions to be developed provide tools and methods to support SE that help practitioners in their work practitioners Prospective SE Practitioner or Manager: Those Secondary Provide an entry level survey to understand what SE is about who may be interested in pursuing a career to someone who has a basic technical or engineering in SE or who need to be aware of SE background practices Interactors: Those who perform in disciplines Secondary Understand basic terminologies, scope, structure, and value of that exchange (consume and/or produce) SE information with SE practitioners Understand the role of the SE practitioner and their relation- ship to others in a project or an organization INCOSE SEH original table created by Yip. Usage per the INCOSE Notices page. All other rights reserved. ORGANIZATION AND STRUCTURE As shown in Figure 0.1, this handbook is organized into six major parts, plus appendices. Systems Engineering Introduction (Part I) provides foundational SE concepts and principles that underpin all other parts. It includes the what and why of SE and why it is important, key definitions, systems science and systems thinking, and SE principles and concepts. FIGURE 0.1 Handbook structure. INCOSE SEH original figure created by Mornas. Usage per the INCOSE Notices page. All other rights reserved. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge.  HOW TO USE THIS HANDBOOK xxiii System Life Cycle Concepts, Models, and Processes (Part II) describes an informative life cycle model with six stages: concept, development, production, utilization, support, and retirement. It also describes a set of life cycle processes to support SE consistent with the four process groups of ISO/IEC/IEEE 15288: Agreement Processes, Organizational Project Enabling Processes, Technical Management Processes, and Technical Processes. Life Cycle Analyses and Methods (Part III) describes a set of quality characteristics approaches that need to be con- sidered across the system life cycle. This part also describes methods that can apply across all processes, reflecting various aspects of the concurrent, iterative, and recursive nature of SE. Tailoring and Application Considerations (Part IV) describes information on how to tailor (adapt and scale) the SE processes. It also introduces various considerations to view and apply SE: SE methodologies and approaches, system types, and project sectors and domains. Systems Engineering in Practice (Part V) describes SE competencies, diversity, equity, and inclusion, SE relation- ship to other disciplines, SE transformation, and insight into the future of SE. Case Studies (Part VI) describes several case studies that are used throughout the handbook to reinforce the SE principles and concepts. Appendix A contains a list of references used in this handbook. Appendices B and C provide a list of acronyms and a glossary of SE terms and definitions, respectively. Appendix D provides an N2 diagram of the SE life cycle processes showing an example of the dependencies that exist in the form of shared inputs or outputs. Appendix E provides a list of all the typical inputs/outputs identified for each SE life cycle process. Appendix F acknowledges the various con- tributors to this handbook. Errors, omissions, and other suggestions for this handbook can be submitted to the INCOSE using instructions found in Appendix G. SYMBOLOGY As described in Section 2.3.1.2, SE is a concurrent, iterative, and recursive process. The following symbology is used throughout this handbook to reinforce these concepts Concurrency is indicated by the parallel lines. Iteration is indicated by the circular arrows. Recursion is indicated by the down and up arrows. TERMINOLOGY One of the SE practitioner’s first and most important responsibilities on a project is to establish nomenclature and ter- minology that support clear, unambiguous communication and definition of the system and its elements, functions, operations, and associated processes. Further, to promote the advancement of the field of SE throughout the world, it is essential that common definitions and understandings be established regarding general methods and terminology that in turn support common processes. As more SE practitioners accept and use common terminology, SE will expe- rience improvements in communications, understanding, and, ultimately, productivity. The glossary of terms used throughout this book (see Appendix C) is based on the definitions found in ISO/IEC/ IEEE 15288; ISO/IEC/IEEE 24765 (2017); and the SEBoK. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. 1 SYSTEMS ENGINEERING INTRODUCTION 1.1 WHAT IS SYSTEMS ENGINEERING? Systems Engineering (SE) Our world and the systems we engineer continue to become more complex and interrelated. SE is an integrative approach to help teams collaborate to understand and manage systems and their complexity and deliver successful systems. The SE perspective is based on systems thinking—a perspective that sharpens our awareness of wholes and how the parts within those wholes interrelate (incose.org, About Systems Engineering). SE aims to ensure the pieces work together to achieve the objectives of the whole. SE practitioners work within a project team and take a holistic, balanced, life cycle approach to support the successful completion of system projects (INCOSE Vision 2035, 2022). SE has the responsibility to realize systems that are fit for purpose, namely that systems accomplish their intended purposes and be resilient to effects in real-world operation, while minimizing unintended actions, side effects, and consequences (Griffin, 2010). Definition of SE INCOSE Definitions (2019) and ISO/IEC/IEEE 15288 (2023) define: Systems Engineering is a transdisciplinary and integrative approach to enable the successful realization, use, and retirement of engineered systems, using systems principles and concepts, and scientific, technological, and management methods. INCOSE Definitions (2019) elaborates: SE focuses on: INCOSE Systems Engineering Handbook: A Guide for System Life Cycle Processes and Activities, Fifth Edition. Edited by David D. Walden, Thomas M. Shortell, Garry J. Roedler, Bernardo A. Delicado, Odile Mornas, Yip Yew-Seng, and David Endler. © 2023 John Wiley & Sons Ltd. Published 2023 by John Wiley & Sons Ltd. 1 This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. 2 Systems Engineering Introduction establishing, balancing and integrating stakeholders’ goals, purpose and success criteria, and defining actual or antic- ipated stakeholder needs, operational concepts, and required functionality, starting early in the development cycle; establishing an appropriate life cycle model, process approach and governance structures, considering the levels of complexity, uncertainty, change, and variety; generating and evaluating alternative solution concepts and architectures; baselining and modeling requirements and selected solution architecture for each stage of the endeavor; performing design synthesis and system verification and validation; while considering both the problem and solution domains, taking into account necessary enabling systems and services, identifying the role that the parts and the relationships between the parts play with respect to the overall behavior and performance of the system, and determining how to balance all of these factors to achieve a satisfactory outcome. SE provides facilitation, guidance, and leadership to integrate the relevant disciplines and specialty groups into a cohesive effort, forming an appropriately structured development process that proceeds from concept to development, production, utilization, support, and eventual retirement. SE considers both the business and the technical needs of acquirers with the goal of providing a quality solution that meets the needs of users and other stakeholders, is fit for the intended purpose in real-world operation, and avoids or minimizes adverse unintended consequences. The goal of all SE activities is to manage risk, including the risk of not delivering what the acquirer wants and needs, the risk of late delivery, the risk of excess cost, and the risk of negative unintended consequences. One measure of utility of SE activities is the degree to which such risk is reduced. Conversely, a measure of acceptability of absence of a SE activity is the level of excess risk incurred as a result. Definitions of System While the concepts of a system can generally be traced back to early Western philosophy and later to science, the con- cept most familiar to SE practitioners is often traced to Ludwig von Bertalanffy (1950, 1968) in which a system is regarded as a “whole” consisting of interacting “parts.” INCOSE Definitions (2019) and ISO/IEC/IEEE 15288 (2023) define: A system is an arrangement of parts or elements that together exhibit behavior or meaning that the individual constituents do not. A system is sometimes considered as a product or as the services it provides. In practice, the interpretation of its meaning is frequently clarified using an associative noun (e.g., medical system, aircraft system). Alternatively, the word “system” is substituted simply by a context-dependent synonym (e.g., pace- maker, aircraft), though this potentially obscures a system principles perspective. A complete system includes all of the associated equipment, facilities, material, computer programs, firmware, technical documentation, services, and personnel required for operations and support to the degree necessary for self-sufficient use in its intended environment. INCOSE Definitions (2019) elaborates: Systems can be either physical or conceptual, or a combination of both. Systems in the physical universe are composed of matter and energy, may embody information encoded in matter-energy carriers, and exhibit observable behavior. Conceptual systems are abstract systems of pure information, and do not directly exhibit behavior, but exhibit “meaning.” In both cases, the system’s properties (as a whole) result, or emerge, from: a) the parts or elements and their individual properties, b) the relationships and interactions between and among the parts, the system, other external systems (including humans), and the environment. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge.  WHAT IS SYSTEMS ENGINEERING? 3 SE practitioners are especially interested in systems which have or will be “systems engineered” for a purpose. Therefore, INCOSE Definitions (2019) defines: An engineered system is a system designed or adapted to interact with an anticipated operational environment to achieve one or more intended purposes while complying with applicable constraints. “Engineered systems” may be composed of any or all of the following elements: people, products, services, information, processes, and/or natural elements. Origins and Evolution of SE Aspects of SE have been applied to technical endeavors throughout history. However, SE has only been formalized as an engineering discipline beginning in the early to middle of the twentieth century (INCOSE Vision 2035, 2022). The term “systems engineering” dates to Bell Telephone Laboratories in the early 1940s (Fagen, 1978; Hall, 1962; Schlager, 1956). Fagen (1978) traces the concepts of SE within the Bell System back to early 1900s and describes major appli- cations of SE during World War II. The British used multidisciplinary teams to analyze their air defense system in the 1930s (Martin, 1996). The RAND Corporation was founded in 1946 by the United States Air Force and claims to have created “systems analysis.” Hall (1962) asserts that the first attempt to teach SE as we know it today came in 1950 at MIT by Mr. Gilman, Director of Systems Engineering at Bell. TRW (now a part of Northrop Grumman) claims to have “invented” SE in the late 1950s to support work with ballistic missiles. Goode and Machol (1957) authored the first book on SE in 1957. In 1990, a professional society for SE, the National Council on Systems Engineering (NCOSE), was founded by representatives from several US corporations and organizations. As a result of growing involvement from SE practitioners outside of the US, the name of the organization was changed to the International Council on Systems Engineering (INCOSE) in 1995 (incose.org, History of Systems Engineering; Buede and Miller, 2016). With the introduction of the international standard ISO/IEC 15288 in 2002, the discipline of SE was formally rec- ognized as a preferred mechanism to establish agreement for the creation of products and services to be traded bet- ween two or more organizations—the supplier(s) and the acquirer(s). This handbook builds upon the concepts in the latest edition of ISO/IEC/IEEE 15288 (2023) by providing additional context, definitions, and practical applications. Table 1.1 provides a list of key SE standards and guides related to the content of this handbook. TABLE 1.1 SE standards and guides Reference Title ISO/IEC/IEEE 15026 Systems and software engineering—Systems and software assurance (Multi-part standard) ISO/IEC/IEEE 15288 Systems and software engineering—System life cycle processes IEEE/ISO/IEC 15289 Systems and software engineering—Content of life cycle information items (documentation) ISO/IEC/IEEE 15939 Systems and software engineering—Measurement process ISO/IEC/IEEE 16085 Systems and software engineering—Life cycle processes—Risk management ISO/IEC/IEEE 16326 Systems and software engineering—Life cycle processes—Project management ISO/IEC/IEEE 21839 Systems and software engineering—System of systems (SoS) considerations in life cycle stages of a system ISO/IEC/IEEE 21840 Systems and software engineering—Guidelines for the utilization of ISO/IEC/ IEEE 15288 in the context of system of systems (SoS) ISO/IEC/IEEE 21841 Systems and software engineering—Taxonomy of systems of systems ISO/IEC/IEEE 24641 Systems and software engineering—Methods and tools for model-based systems and software engineering (Continued) This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. 4 Systems Engineering Introduction TABLE 1.1 (Continued) Reference Title ISO/IEC/IEEE 24748–1 Systems and software engineering—Life cycle management—Part 1: Guidelines for life cycle management ISO/IEC/IEEE 24748–2 Systems and software engineering—Life cycle management—Part 2: Guidelines for the application of ISO/IEC/IEEE 15288 ISO/IEC/IEEE 24748–4 Systems and software engineering—Life cycle management—Part 4: Systems engineering planning ISO/IEC/IEEE 24748–6 Systems and software engineering—Life cycle management—Part 6: System integration engineering ISO/IEC/IEEE 24748–7 Systems and software engineering—Life cycle management—Part 7: Application of systems engineering on defense programs ISO/IEC/IEEE 24748–8 / IEEE 15288.2 Systems and software engineering—Life cycle management—Part 8: Technical reviews and audits on defense programs ISO/IEC/IEEE 24765 Systems and software engineering—Vocabulary ISO/IEC/IEEE 26550 Software and systems engineering—Reference model for product line engineering and management ISO/IEC/IEEE 26580 Software and systems engineering—Methods and tools for the feature-based approach to software and systems product line engineering ISO/IEC/IEEE 29148 Systems and software engineering—Life cycle processes—Requirements engineering ISO/IEC/IEEE 42010 Systems and software engineering—Architecture description ISO/IEC/IEEE 42020 Software, systems and enterprise—Architecture processes ISO/IEC/IEEE 42030 Software, systems and enterprise—Architecture evaluation framework ISO/IEC 29110 Systems and Software Engineering Standards and Guides for Very Small Entities (VSEs) (Multi-part set) ISO/IEC 31000 Risk management ISO/IEC 31010 Risk management—Risk assessment techniques ISO/IEC 33060 Process assessment—Process assessment model for system life cycle processes ISO/PAS 19450 Automation systems and integration—Object-Process Methodology (OPM) ISO 10007 Quality management—Guidelines for configuration management ISO 10303-233 Industrial automation systems and integration—Product data representation and exchange—Part 233: Application protocol: Systems engineering NIST SP 800–160 Vol. 1 Systems Security Engineering: Considerations for a Multidisciplinary Approach in the Engineering of Trustworthy Secure Systems NIST SP 800–160 Vol. 2 Developing Cyber-Resilient Systems: A Systems Security Engineering Approach OMG SysMLTM OMG Systems Modeling Language SEBoK Guide to the Systems Engineering Body of Knowledge (SEBoK) SAE-EIA 649C Configuration Management Standard SAE 1001 Integrated Project Processes for Engineering a System (Note: Replaced ANSI/EIA 632) ANSI/AIA.A G.043B Guide to the Preparation of Operational Concept Documents CMMI CMMI® V2.0 INCOSE SEH original table created by Mornas, Roedler, and Walden. Usage per the INCOSE Notices page. All other rights reserved. 1.2 WHY IS SYSTEMS ENGINEERING IMPORTANT? The purpose of SE is to conceive, develop, produce, utilize, support, and retire the right product or service within budget and schedule constraints. Delivering the right product or service requires a common understanding of the current system state and a common vision of the system’s future states, as well as a methodology to transform a set of stakeholder needs, expectations, and constraints into a solution. The right product or service is one that accomplishes This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge.  WHY IS SYSTEMS ENGINEERING IMPORTANT? 5 the required service or mission. A common vision and understanding, shared by acquirers and suppliers, is achieved through application of proven methods that are based on standard approaches across people, processes, and tools. The application of these methods is continuous throughout the system’s life cycle. SE is particularly important in the presence of complexity (see Section 1.3.7). Most current systems are formed by integrating commercially available products or by integrating independently managed and operated systems to provide emergent capabilities which increase the level of complexity (see Sections 4.3.3 and 4.3.6). This increased reliance on off-the-shelf and systems of systems has significantly reduced the time from concept definition to market availability of products. Over the years between 1880 and 2000, average 25% market penetration has been reduced by more than a factor of four as illustrated in Figure 1.1. In response to complexity and compressed timelines, SE methods and tools have become more adaptable and effi- cient. Introduction of agile methods (see Section 4.2.2) and SE modeling language standards such the Systems Modeling Language (SysML) have allowed SE practitioners to manage complexity and increase the implementation of a common system vision (see bottom of Figure 1.1). Model Based SE (MBSE) methods adoption continues to grow (see Section 4.2.1), particularly in the early conceptual design and requirements analysis (SEBOK, Emerging Topics). MBSE research literature continues to report on the increased productivity and quality of design and promises further progression toward a digital engineering (DE) approach, where data is transparent and cooperation optimized across all engineering disciplines. Standards organizations are updating or developing new approaches that take DE into consideration. SE will have to address this new digital representation of the system as DE becomes the way of doing business (see Section 5.4). The rapid evolution and introduction of Artificial Intelligence (AI) and Machine Learning (ML) into SE further increases complexity of verifiability, safety, and trust of self-learning and evolving systems. The overall value of SE has been the subject of studies and papers from many organizations since the introduction of SE. A 2013 study was completed at the University of South Australia to quantify the return on investment (ROI) of SE activities on overall project cost and schedule (Honour, 2013). Figure 1.2 compares the total SE effort with cost 60 Years to penetrate market at 25% Car Increased component integration 50 Radio 40 ~ 44 YEARS Phone ~ 30 YEARS VCR Microwave ~17 YEARS 30 Electricity TV Internet 20 Trend has Cell continued 10 Development and Market Penetration Have Accelerated by a Factor of 4 PC 0 1860 1880 1900 1920 1940 1960 1980 2000 Prototype development date Systems Engineering Approach Off-the-shelf integration continues to reduce Bell Laboratories time to market requiring increasingly more efficient and adaptable approaches and tools Complexity MoD Air Defense Commercially Agile, Modular, Standardization Driven Process & Model Driven Invention Adoption Gov. Driven Process Standards Methods Paper Based Model Based FIGURE 1.1 Acceleration of design to market life cycle has prompted development of more automated design methods and tools. INCOSE SEH original figure created by Amenabar. Usage per the INCOSE Notices page. All other rights reserved. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. 6 Systems Engineering Introduction FIGURE 1.2 Cost and schedule overruns correlated with SE effort. From Honour (2013) with permission from University of South Wales. All other rights reserved. compliance (left figure) and schedule performance (right figure). In both graphs, increasing the percentage of SE within the project results in better success up to an optimum level, above which SE ROI is diminished above those total program expenditure levels due to increased unwarranted processes. Study data shows that SE effort had a significant, quantifiable effect on project success, with correlation factors as high as 80%. Results show that the optimum level of SE effort for a normalized range of 10% to 14% of the total project cost. The ROI of adding additional SE activities to a project is shown in Table 1.2, and it varies depending on the level of SE activities already in place. If the project is using no SE activities, then adding SE carries a 7:1 ROI; for each cost unit of additional SE, the project total cost will reduce by 7 cost units. At the median level of the projects interviewed, additional SE effort carries a 3.5:1 ROI. A joint 2012 study by the National Defense Industrial Association (NDIA), the Institute of Electrical and Electronic Engineers (IEEE), and the Software Engineering Institute (SEI) of Carnegie Mellon University (CMU) surveyed 148 development projects and found clear and significant relationships between the application of SE activities and the performance of those projects as seen in Figure 1.3 (Elm and Goldenson, 2012). The study broke the projects by the maturity of their SE processes as measured by the quantity and quality of specific SE work products and considered the complexity of each project and the maturity of the technologies being implemented (n=number of projects). It also assessed the levels of project performance, as measured by satisfaction of budget, schedule, and technical require- ments. The left column represents those projects deploying lower levels of SE expertise and capability. Among these projects, only 15% delivered higher levels of project performance and 52% delivered lower levels of project performance. The center column represents those projects deploying moderate levels of SE expertise and capability. Among these projects, the number delivering higher levels of project performance increased to 24% and those deliv- ering lower levels decreased to 29%. The right column represents those projects deploying higher levels of SE exper- tise and capability. For these projects, the number delivering higher levels of project performance increased substantially TABLE 1.2 SE return on investment ROI for additional SE effort (cost Current SE effort (% of program cost) Average cost overrun (%) reduction $ per $ SE added) 0 53 7.0 5 24 4.6 7.2 (median of all programs) 15 3.5 10 7 2.1 15 3 –0.3 20 10 –2.8 From Honour (2013) with permission from University of South Wales. All other rights reserved. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge.  WHY IS SYSTEMS ENGINEERING IMPORTANT? 7 Program performance vs. total SE to 57%, while those delivering lower levels decreased 100% to 20%. As Figure 1.3 shows, well-applied SE increases 15% Higher the probability of successfully developing an Program performance (perf ) 24% 80% perf engineered system. 33% 57% A 1993 Defense Acquisition University (DAU) 60% 47% Middle statistical analysis on US Department of Defense perf 40% (DoD) projects examined spent and committed life 52% 24% cycle cost (LCC) over time (DAU, 1993). As illustrated 20% Lower 29% perf notionally in Figure 1.4, an important result from this 20% 0% study is that by the time approximately 20% of the Lower SEC Middle SEC Higher SEC All actual costs have been accrued, over 80% of the total (n = 48) (n = 49) (n = 51) projects LCC has already typically been committed. Figure 1.4 Total systems engineering capability (SEC) also shows that it is less costly to fix or address issues Gamma = 0.49 p-value < 0.001 if they are identified early. Good SE practice is the means by which the issues are identified and ensures FIGURE 1.3 Project performance versus SE capability. From that the understanding obtained is applied as appro- Elm and Goldenson (2012) with permission from Carnegie Mellon University. All other rights reserved. priate during the life cycle, thus reducing technical debt. INCOSE maintains value proposition statements (INCOSE Value Strategic Initiative Report, 2021) as tailored to different areas and industries. Areas covered include individual INCOSE membership, organizational INCOSE membership, INCOSE SE certification, and the discipline of SE. Industries include commercial, government, and nonprofit organizations. A sample of these findings includes: FIGURE 1.4 Life cycle costs and defect costs against time. INCOSE SEH original figure created by Walden derived from DAU (1993). Usage per the INCOSE Notices page. All other rights reserved. This PDF copy of the SE Handbook, Fi h Edi on is for the member's personal use only and may not be uploaded to a publicly accessible website or systema cally distributed, whether or not for commercial or non-profit use, whether for a fee or free of charge. 8 Systems Engineering Introduction Value of SE to the Commercial/Market-Driven Industry: Companies and other enterprises in commercial industry will benefit from the internal practice of professional SE by having enhanced their capability for the development of innovative products and services for distribution in both mature and immature markets, in a more efficient and competitive manner. Value of SE to Government/Infrastructure/Aerospace/Defense Industry: SE provides a tailorable, systematic approach to all stages of a project, from concept to retirement. SE can accommodate different approaches including agile and sequential and facilitate commonality and open architectures to ensure lower acquisition, maintenance, and upgrade costs. By confirming correct and complete requirements and requirements allocations, the resulting design has fewer and less significant changes resulting in improved overall cost and schedule performance. Value of SE to Nonprofit/Research Industry: A nonprofit enterprise will benefit from the internal practice of professional SE by having enhanced their capability for the development of innovative client services in a more efficient and effective manner. An enterprise engaged in basic or applied research will benefit from the internal practice of SE by having enhanced its capabilities for discovery and invention that supports technology d