Analysis_Weapon Systems Annual Assessment

The Sentinel program’s estimated costs surged by $36 billion in 2025, which accounts for 73% of the total $49.3 billion increase across 30 Major Defense Acquisition Programs (MDAPs). This level of cost growth is disproportionate compared to other programs and indicates significant inefficiencies.

1.Problem

Excerpt from GAO report released June 2025

What GAO Found:

The Department of Defense (DOD) continues to struggle with delivering innovative technologies quickly and within budget.

Since its last annual assessment, GAO found:

• Program development delays and inflation, among other things, contributed to cost growth in the major defense acquisition program (MDAP) portfolio.

• Programs spent development time on efforts with low levels of maturity while using the middle tier of acquisition (MTA) pathway intended for speed.

• Future major weapon acquisitions (newer efforts that have yet to begin on a pathway) did not take full advantage of product development practices that lead to efficiencies.

Program challenges and inflation drove major defense acquisition program portfolio costs. Combined total estimates increased by $49.3 billion for 30 MDAPs also included in last year’s report.

The Air Force’s Sentinel missile program accounted for over $36 billion (73 percent) of this increase.

2. Analysis

Key Issues Identified

Addressing the largest cash cow first: Sentinel is designed as a full replacement system, not an incremental upgrade - this “big bang” approach forces upfront investment in infrastructure before any operational capability is fielded—raising cost risk without early return on capability.

• Cost Growth in MDAP Portfolio

  • $49.3 billion increase across 30 programs; 73% attributable to the Air Force’s Sentinel missile program.

  • Drivers: inflation, program delays, and technical immaturity.

• Low Maturity in Development

  • Programs pursued under the Middle Tier of Acquisition (MTA) pathway without adequate technology readiness.

  • MTA intended for speed, but immaturity led to extended timelines and cost overruns.

• Limited Adoption of Proven Practices

  • Future programs are not implementing best practices in product development such as modular open systems architectures, rigorous systems engineering, and early prototyping.

• Systemic Risk Factors

  • Over-optimism in scheduling: Unrealistic timelines drive aggressive execution without sufficient tech maturation.

  • Inflation impact underestimated: Budget planning did not fully account for multi-year economic variability.

  • Inadequate governance in MTA: The MTA pathway bypasses some traditional milestones, but oversight of tech maturity is inconsistent.

  • Cultural bias toward speed over rigor: Programs often prioritize rapid delivery mandates without investing in early risk reduction.

• Specific Sentinel Impact

  • Sentinel’s cost spike signals high complexity risk, likely due to:

    • Nuclear modernization challenges.

    • Long-term infrastructure requirements.

      such as vendor base constraints and workforce shortages.

  3. Recommendations

  A. Strengthen Technology Readiness Oversight

  • Mandate TRL (Technology Readiness Level) thresholds before MTA initiation.

  • Implement independent tech assessments by the Defense Innovation Board or a GAO-aligned oversight cell.

  B. Refine Middle Tier of Acquisition (MTA) Governance

  • Create tiered risk-based gates within the MTA pathway:

    • Gate 1: Demonstrated prototype validation.

    • Gate 2: Independent cost-risk analysis.

  • Require regular independent reviews even for MTA programs, ensuring transparency on schedule and cost projections.

  C. Accelerate Modular Open Systems and Digital Engineering

  • Require digital twin and model-based systems engineering (MBSE) for all new MDAPs.

  • Incentivize contractors to adopt open architecture standards for faster integration and lower lifecycle costs.

  D. Improve Cost and Schedule Realism

  • Adopt dynamic cost modeling with inflation sensitivity.

  • Utilize should-cost management and link contractor incentives to mature tech delivery, not just production speed.

  E. Expand Early Prototyping and Experimentation

  • Shift more funding to Rapid Prototyping prior to full development.

  • Leverage Defense Innovation Unit (DIU) and AFWERX partnerships to validate tech maturity before MDAP inclusion.

  F. Enhance Workforce and Vendor Base Resilience

  • Address industrial base fragility with long-lead investments in materials and skilled labor.

  • Expand use of public-private innovation hubs to accelerate manufacturing readiness.

  G. Sentinel Program-Specific Actions

  • Conduct root-cause analysis on Sentinel overruns.

  • Break Sentinel modernization into incremental capability releases to manage complexity and risk.

  • Establish executive-level cost containment board to track major nuclear modernization programs.