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What GAO Found

The Department of Defense (DOD) and Air Force do not have quality information on the full implications of A-10 divestment, including gaps that could be created by A-10 divestment and mitigation options. While A-10 pilots are recognized as the Air Force experts in providing close air support (CAS) to friendly forces, the A-10 and its pilots also perform other missions that are important to ongoing operations or to combatant commander operational plans and divestment will result in reduced capacity and capability in these other areas. The Air Force is taking a number of steps to try to mitigate any potential negative impacts from its proposed A-10 divestments. However, the Air Force has not established clear requirements for the missions the A-10 performs, and in the absence of these requirements, has not fully identified the capacity or capability gaps that could result from the A-10 divestment. Without a clear understanding of the capability or capacity gaps and risks that could result from A-10 divestment, it is also unclear how effective or necessary the Air Force's and the department's mitigation strategies will be. For example, although the Air Force has several efforts underway to generally mitigate the loss of capabilities that would result from A-10 divestment, it has not identified how or if it will replace the A-10's role in combat search and rescue missions. Depending on the specific mitigation strategy chosen, the Air Force may have to address a number of different secondary impacts that could affect its ability to execute existing missions. The A-10 is one example of a challenge DOD could continue to face as it balances current needs against investing in the future force to replace aging systems. For example, in June 2014, GAO reported on a Navy challenge in balancing current capability and capacity with future modernization needs. Overall, the department does not have guidance to ensure that the services and DOD are collecting quality information to inform divestment decisions on major weapon systems before the end of their service lives. Without quality information that fully identifies gaps and associated risks resulting from divestment that can be used to develop mitigation strategies, DOD and the Air Force may not be well-positioned to best balance current demands and future needs.

According to the GAO Cost Estimating and Assessment Guide , a high-quality, reliable cost estimate is comprehensive, well-documented, accurate, and credible. GAO's analysis found that the Air Force's cost estimate for its fiscal year 2015 divestment proposal partially met best practices for being comprehensive, minimally met best practices for being well-documented and accurate, and did not meet best practices for being credible. Additionally, Air Force officials stated they used similar practices when developing fiscal years 2016 and 2017 budget requests that included A-10 divestment. As a result, the Air Force cannot ensure that it has a reliable estimate of the cost savings it would generate by divesting the A-10. Further, without developing a reliable estimate, the Air Force does not have a sound basis from which to develop and consider alternatives to achieve budget targets, such as making adjustments to other fighter-attack programs or mission areas like air superiority or global strike.

This is a public version of a classified report GAO issued previously. It excludes classified information which described specific intelligence assessments, scenarios, and operational details.

Why GAO Did This Study

DOD faces difficult decisions on how to best balance current demands and future needs within fiscal constraints. Decisions regarding the A-10 aircraft exemplify the difficulty. In the fiscal year 2015 budget request, DOD and the Air Force prioritized modern multi-role aircraft and proposed divesting the A-10 fleet, but Congress prohibited this action. DOD and the Air Force have continued to propose divesting the A-10 in two subsequent budget requests.

The National Defense Authorization Act for Fiscal Year 2015 included a provision for GAO to review the A-10 divestment proposal. This report reviews the extent to which (1) the Air Force and DOD have quality information needed to understand the implications of A-10 divestment; and (2) the Air Force followed best practices when estimating cost savings from A-10 divestment and evaluating alternatives. GAO analyzed agency documents and interviewed knowledgeable officials for this review.

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With regard to the A-10, GAO recommends that the Air Force fully identify mission gaps, risks, and mitigation strategies, and also develop high-quality, reliable cost estimates of the savings from divestment before again proposing to divest its A-10 fleet, and that DOD establish quality information requirements to guide major weapon system divestments. DOD non-concurred with the recommendations, but GAO continues to believe that they remain valid as discussed in the report.

Recommendations for Executive Action

Agency Affected Recommendation Status
Department of the Air Force 1. To make a well-informed decision about the future of its A-10 aircraft, before again recommending divestment of the A-10, the Secretary of the Air Force should: (1) Develop quality information that fully identifies gaps in capacity or capability that would result from A-10 divestment, including the timing and duration of any identified gaps, and the risks associated with those gaps; and (2) Use that information to develop strategies to mitigate any identified gaps.
Closed - Implemented
The Air Force non-concurred with the recommendation, stating that it had sufficient understanding of the risks and the capability gaps when deciding to divest the A-10. However, in December 2016, Congress passed the fiscal year 2017 National Defense Authorization Act (PL 114-328), which included a provision prohibiting the Air Force from retiring the A-10 until certain conditions were met. Further, and consistent with our recommendation to develop quality information, the Air Force conducted a force structure study and found a continued need for the A-10. Specifically, the Air Force published a study in March 2019 that examined aircraft inventory needs through 2030 and recommended increasing the number of fighter squadrons from 55 to 62, which include the A-10. According to Air Force officials, the study found that the A-10 fulfills some National Defense Strategy objectives and priorities and so was not considered for divestment. In a July 2020 response to GAO, the Air Force also stated that it conducted an internal study in 2016 that assumptions used for past force structure decisions required revisions. This study determined, among other things, that the A-10 should be retained into the 2030s. These studies meet the intent of our recommendation.
Department of the Air Force 2. To further inform decisions about the future of the A-10, the Secretary of the Air Force should, in considering divestment, develop a high-quality, reliable cost estimate utilizing best practices.
Closed - Not Implemented
The Air Force non concurred with this recommendation, stating that it used programming and sustainment data to inform their cost estimate. As of August 2020, DOD confirmed that it retains its original position on this recommendation and has taken no implementation actions. We continue to believe our recommendation is valid but are closing it due to DOD's reluctance to take action.
Department of Defense 3. To ensure that senior leaders have the quality information on which to base future force structure decisions, the Secretary of Defense should develop and promulgate department-wide guidance that establishes specific informational requirements to be met before proposing divestment of major weapon systems that have not reached the end of their expected service lives.
Closed - Not Implemented
DOD non concurred with the recommendation, stating the department already has guidelines and robust procedures in place to provide senior leaders with quality information with which to make divestment decisions, including through budgeting and acquisition processes. As of August 2020, DOD confirmed that it still does not concur and has not taken action to implement this recommendation. We continue to believe that our recommendation is valid but are closing it as not implemented due to DOD's reluctance to take action.

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