Government Accountability Office: Annual Assessment of Weapon Systems (--)

Key Chapter Title List

1. Background
2. DOD Plans to Invest Nearly $2.4 Trillion in Its Weapons Portfolio
3. Plans Miss Opportunities to Deliver Capabilities with Speed
4. Plans Could Improve Oversight of Software Development
5. Conclusion
6. Recommendations for Executive Action
7. Appendix I: Program Assessments
8. Appendix II: Objectives, Scope, and Methodology
9. Appendix III: DOD's Responsibilities for Weapon System Acquisition
10. Appendix IV: Leading Product Development Practices Across Iterative Cycles
11. Appendix V: Technology Readiness Levels
12. Appendix VI: Comments from the Department of Defense

Document Introduction

This report is the 23rd annual assessment submitted by the U.S. Government Accountability Office (GAO) to congressional committees, fulfilling the statutory duty under Title 10 U.S.C. § 3072 to review the Department of Defense's (DOD) most expensive weapon acquisition programs. The report focuses on DOD's longstanding challenge of rapidly delivering innovative technologies within its weapons portfolio, particularly against a backdrop of increasingly complex, software-driven technologies and heightened threats from peer adversaries. Although DOD has implemented reforms aimed at accelerating outcomes, slow, linear development approaches persist.

The report's core analysis covers 106 of DOD's most expensive weapon programs, including 79 Major Defense Acquisition Programs (MDAPs), 20 programs using the Middle Tier of Acquisition (MTA) pathway, and 7 future major weapon acquisitions that have not yet started an acquisition pathway. By analyzing cost and schedule data, collecting program documents, administering questionnaires, and interviewing DOD officials, the report assessed these programs' performance over time, analyzed opportunities to improve program outcomes using leading product development practices, and examined the extent to which programs implement modern software development methods and recommended cybersecurity practices.

The study found that the cost of DOD's weapon program portfolio continues to grow, and schedule delays are worsening. For example, the total estimated cost for 30 MDAPs consistently included in the assessment increased by $49.3 billion, with the Air Force's Sentinel missile program contributing over $36 billion of that increase. The average projected time for MDAPs to deliver initial capability to warfighters increased by 18 months, reaching nearly 12 years. The MTA pathway, designed to accelerate capability delivery, has not fully achieved its intent; some programs entered this pathway with low technology maturity, leading to prolonged development rather than the expected speed. Furthermore, future major weapon acquisition programs are not planning to fully leverage efficiency-enabling leading product development practices before initiation.

The report emphasizes that most reviewed programs failed to implement key leading practices—such as Modular Open Systems Approach, Minimum Viable Product, Digital Twins, and Digital Thread—in a coordinated and comprehensive manner. The fragmented use of these practices limits the potential for weapon systems to iterate rapidly, adapt to new threats, and maximize cost-effectiveness. The report also notes that programs have room for improvement in software development and cybersecurity practices, including insufficient adoption of agile development metrics and tools, and inconsistent execution of early cybersecurity testing.

Based on these findings, GAO made recommendations to DOD leadership to take actions ensuring that future major weapon acquisition programs incorporate leading product development practices from their earliest stages. DOD agreed with these recommendations. This report provides a decision-making tool for Congress and DOD leadership, offering a quick overview of each program's performance, risks, development progress, and use of leading practices, aiming to promote wiser investment of taxpayer funds and faster delivery of weapon systems.