Limited Print and Electronic Distribution Rights
This document and trademark(s) contained herein are protected by law. This representation of RAND
intellectual property is provided for noncommercial use only. Unauthorized posting of this publication
online is prohibited. Permission is given to duplicate this document for personal use only, as long as it
is unaltered and complete. Permission is required from RAND to reproduce, or reuse in another form, any of
its research documents for commercial use. For information on reprint and linking permissions, please visit
www.rand/pubs/permissions.
The RAND Corporation is a research organization that develops solutions to public policy challenges to help make
communities throughout the world safer and more secure, healthier and more prosperous. RAND is nonprofit,
nonpartisan, and committed to the public interest.
RAND’s publications do not necessarily reflect the opinions of its research clients and sponsors.
Support RAND
Make a tax-deductible charitable contribution at
www.rand/giving/contribute
www.rand
For more information on this publication, visit www.rand/t/RR2500
Library of Congress Cataloging-in-Publication Data is available for this publication.
ISBN: 978-1-9774-0072-7
Published by the RAND Corporation, Santa Monica, Calif.
Copyright 2018 RAND Corporation
R is a registered trademark.
iii
Preface
The 1997 National Defense Authorization Act (NDAA) directed the Department of Defense to
conduct a systematic review of U.S. defense needs every four years. The first of these
Quadrennial Defense Reviews (QDRs) was conducted in 1997, followed by four others in 2001,
2006, 2010, and 2014. By 2016, congressional leaders viewed the QDR as a costly “watered-
down, consensus-driven product” of relatively little value.1 As a result, the 2017 NDAA
scrapped the QDR, replacing it with two strategy documents. By 2017, this had evolved into a
requirement for a single review of the National Military Strategy.
Recognizing that some kind of defense strategy review would occur in 2017–2018, the
Director, Strategy, Concepts and Assessments, Headquarters, U.S. Air Force (USAF),
commissioned a fiscal year 2017 RAND Project AIR FORCE study. The USAF sought help
developing a force planning and sizing construct that would address two competing demands: (1)
Deter (and, if necessary, win) a future conflict with a major power and (2) meet recurring and
often enduring combatant commander demands for forces today. These are in tension because
the current force is neither sized nor resourced to meet the demands of current operations,
maintain a large force in high readiness for major conflict, and fund needed modernization to
counter emerging challenges.
To address these and related policy issues, the study was organized around five research
questions: (1) Do defense reviews matter, and, if so, how can the USAF participate most
effectively (2) What programs should the USAF prioritize to deter/defeat peer threats (3) How
do military operations become prolonged2 (4) What types of force demands have been placed
on the USAF since the end of World War II and (5) What impact do steady-state demands,
prolonged military operations, and other contingencies have on USAF force structure
This report addresses the last two questions. Specifically, the purposes of this report are to
quantify historical demands placed on the Air Force and to use that historical evidence to help
identify future potential capacity shortfalls, indicate which aircraft platforms might or might not
be placed in short supply under different scenarios, suggest where capacity increases could
enhance force robustness, and inform force planning more generally. The report does not address
specific causes of stress in the current force other than to note the role of prolonged operations in
creating excessive demand relative to the fiscal year 2017 force.
For documentation of our analysis on the other questions, see Raphael S. Cohen,
The History
and Politics of Defense Reviews
,
Santa Monica, Calif.: RAND Corporation, RR-2278-AF, 2018;
1 Joe Gould, “QDR Dead in 2017 Defense Policy Bill,”
Defense News
, April 25, 2016.
2 We define “prolonged” operations as those lasting more than a year.
iv
and David Ochmanek,
Restoring U.S. Power Projection Capabilities: Responding to the 2018
National Defense Strategy
, Santa Monica, Calif.: RAND Corporation, PE-260-AF, 2018.
The research described in this report was conducted within the Strategy and Doctrine
Program of RAND Project AIR FORCE.
RAND Project AIR FORCE
RAND Project AIR FORCE (PAF), a division of the RAND Corporation, is the U.S. Air Force’s
federally funded research and development center for studies and analyses. PAF provides the Air
Force with independent analyses of policy alternatives affecting the development, employment,
combat readiness, and support of current and future air, space, and cyber forces. Research is
conducted in four programs: Force Modernization and Employment; Manpower, Personnel, and
Training; Resource Management; and Strategy and Doctrine. The research reported here was
prepared under contract FA7014-16-D-1000.
Additional information about PAF is available on our website:
www.rand/paf.
This report documents work originally shared with the U.S. Air Force on July 13, 2017. The
draft report, issued on September 22, 2017, was reviewed by formal peer reviewers and U.S. Air
Force subject-matter experts.
v
Contents
Preface ....... iii
Figures ...... vii
Tables ...... viii
Summary ...... x
Acknowledgments ......... xviii
Abbreviations ....... xix
Chapter One: Introduction ... 1
Background ........... 1
The Policy Problem ........... 2
Purpose of This Report ...... 2
Organization .......... 3
Chapter Two: An Overview of Joint Operations: 1946–2016 ......... 4
Introduction ........... 4
Descriptive Statistics, 1946–2016 . 6
Prolonged Operations ........ 9
Prolonged Operations by Mission Type ........... 9
Length of Prolonged Operations by Mission Type ..... 10
Simultaneity and Prolonged Operations ......... 11
Prolonged Operations by Presidential Administration ........... 12
Are Operations Becoming Longer .... 13
Chapter Three: Analytical Approach ......... 15
Derivation of Future Decremented Supply ......... 15
Total Supply .... 15
Fixed Demand . 16
Decremented Supply ... 19
Estimation of Future Variable Demands . 19
Futures 1 and 2: New Cold War ......... 20
Future 3: Peace Enforcement .. 22
Future 4: Global Counterterrorism and Counterinsurgency Operations ......... 23
Construction of Representative Force Packages . 25
Prediction of Operational Durations ....... 28
Translation of Aircraft Demands into Squadron Demands ......... 29
Accommodation of Key Scheduling Constraints30
Chapter Four: Force Structure Implications of Alternative Futures .......... 33
Base Case33
Analytical Excursions ..... 36