F-35 Sustainment: DOD Needs to Cut Billions in Estimated Costs to Achieve Affordability

GAO-21-439 Published: Jul 07, 2021. Publicly Released: Jul 07, 2021.
Jump To:
Fast Facts

DOD plans to acquire nearly 2,500 F-35 aircraft for about $400 billion. It projects spending another $1.27 trillion to operate and sustain them—an estimate that has steadily increased since 2012.

The military services collectively face tens of billions of dollars in sustainment costs that they project will be unaffordable. For example, the Air Force needs to reduce estimated annual per-plane costs by $3.7 million (47%) by 2036, or costs in that year alone will be $4.4 billion more than it can afford.

We recommended, among other things, that Congress consider making future F-35 acquisitions contingent on progress reducing sustainment costs.

An F-35B Performing a Vertical Landing at Naval Air Station Patuxent in Maryland

Skip to Highlights
Highlights

What GAO Found

F-35 mission capable rates—a measure of the readiness of an aircraft fleet—have recently improved, but still fall short of warfighter requirements. Specifically, from fiscal year 2019 to fiscal year 2020, the U.S. F-35 fleet's average annual (1) mission capable rate—the percentage of time during which the aircraft can fly and perform one of its tasked missions—improved from 59 to 69 percent; and (2) full mission capable rate—the percentage of time during which the aircraft can perform all of its tasked missions—improved from 32 to 39 percent. Both metrics fall below the services' objectives. For example, in fiscal year 2020 the Air Force F-35A full mission capable rate was 54 percent, versus a 72 percent objective.

Since 2012, F-35 estimated sustainment costs over its 66-year life cycle have increased steadily, from $1.11 trillion to $1.27 trillion, despite efforts to reduce costs. The services face a substantial and growing gap between estimated sustainment costs and affordability constraints—i.e., costs per tail (aircraft) per year that the services project they can afford—totaling about $6 billion in 2036 alone (see fig.). The services will collectively be confronted with tens of billions of dollars in sustainment costs that they project as unaffordable during the program.

Gap between F-35 Affordability Constraints and Estimated Sustainment Costs in 2036

Gap between F-35 Affordability Constraints and Estimated Sustainment Costs in 2036

Note: Costs are in constant year 2012 dollars, as that was the year when the F-35 program was most recently re-baselined.

aSteady state years for the F-35 program are defined in each respective service's affordability analysis as: US Air Force/F-35A – 2036-2041; US Marine Corps/F-35B – 2033-2037; US Navy/F-35C – 2036-2043. Steady state refers to the program's peak operating point.

The Air Force needs to reduce estimated costs per tail per year by $3.7 million (or 47 percent) by 2036 or it will incur $4.4 billion in costs beyond what it currently projects it could afford in that year alone. Cost reductions become increasingly difficult as the program grows and matures. However, GAO found that there is no agreed upon approach to achieve the constraints. The F-35 program estimates that it will declare Milestone C—a decision point for moving into full-rate production of the aircraft—sometime in the 2021-2023 time frame. Without assessing cost-reduction efforts and program requirements (such as number of planned aircraft), and developing a plan prior to declaring Milestone C, the Department of Defense (DOD) may continue to invest resources in a program it ultimately cannot afford. Congress's requiring DOD to report on its progress in achieving affordability constraints and making F-35 procurements contingent on DOD's demonstrated progress would enhance DOD's accountability for taking the necessary and appropriate actions to afford sustaining the F-35 fleet.

Why GAO Did This Study

The F-35 aircraft, with its advanced capabilities, represents a growing portion of DOD's tactical aviation fleet—with about 400 of the aircraft fielded. DOD plans to procure nearly 2,500 F-35s at an estimated life cycle costs of the program exceeding $1.7 trillion—with $1.3 trillion of those costs being associated with operating and sustaining the aircraft.

A House Report accompanying the National Defense Authorization Act for Fiscal Year 2020 included a provision for GAO to review F-35 sustainment efforts. This report, among other things, assesses the extent to which (1) the F-35 has met warfighter-required mission capable rates; and (2) DOD has reduced the F-35's estimated life cycle sustainment costs and made progress in meeting its affordability constraints. GAO reviewed program documentation, analyzed performance and cost data, collected data from F-35 locations, and interviewed officials.

Skip to Recommendations

Recommendations

Congress should consider (1) requiring DOD to report annually on progress in achieving the affordability constraints, and (2) making F-35 aircraft procurement decisions contingent on DOD's progress in achieving these constraints. GAO is making four recommendations to DOD, including assessing cost reduction efforts and F-35 program requirements, and developing a plan to afford to sustain the future F-35 fleet. DOD partially concurred stating it will work to meet the intent of the recommendations in an expeditious manner. GAO continues to believe DOD should address the recommendations prior to declaring Milestone C.

Matter for Congressional Consideration

Matter Status Comments
Congress should consider requiring the Under Secretary of Defense for Acquisition and Sustainment, in consultation with the services and the F-35 Joint Program Office, to report annually on progress in achieving the services' affordability constraints, including the actions taken and planned to reduce sustainment costs. (Matter for Consideration 1)
Open
As of March 2023, Congress has not required the Department of Defense to report annually on the progress in achieving the service's affordability constraints.
Congress should consider making future F-35 aircraft procurement decisions contingent on DOD's progress in achieving F-35 sustainment affordability constraints. (Matter for Consideration 2)
Closed – Implemented
In Section 141 of the National Defense Authorization Act for Fiscal Year 2022, Congress took steps to limit the quantity of F-35s procured by the military services beginning in fiscal year 2029 based on their ability to achieve affordability cost targets. These steps meet the intent of our matter for consideration; therefore, we are closing this action.

Recommendations for Executive Action

Agency Affected Recommendation Status
Department of Defense The Secretary of Defense should ensure that, prior to the Milestone C decision, the Under Secretary of Defense for Acquisition and Sustainment, in consultation with the services and the F-35 Joint Program Office, assess and document DOD's ability to meet the services' affordability constraints with existing or planned cost-reduction efforts. (Recommendation 1)
Open
DOD agreed with the substance of the recommendation and is currently taking actions to address the recommendation. As of February 2023, DOD officials told us that the F-35 Joint Program Office is using specific activities, including Plan of Actions and Milestones, to drive affordability cost reduction efforts. These activities will also include timelines, resource requirements, assumptions, and risks against the current military service-provided affordability constraints. DOD plans to document all of these efforts in an update to the F-35's Life Cycle Sustainment Plan; however, the completion date of this update is undetermined. Until we are able to review the updated F-35 Life Cycle Sustainment Plan and determine the extent to which DOD has documented its ability to meet the military services' affordability constraints, this recommendation will remain open.
Department of Defense The Secretary of Defense should ensure that, prior to the Milestone C decision, the Under Secretary of Defense for Acquisition and Sustainment, in consultation with the services and the F-35 Joint Program Office, assess and document changes in service-related program requirements (e.g., the number of aircraft purchases and flying hours) to achieve cost-reductions. (Recommendation 2)
Open
DOD agreed with the substance of the recommendation. According to DOD officials, as part of the military services' fiscal year 2023 budget requests, the military services provided analyses of their most up-to-date assessments of future aircraft purchases and flying hour plans. DOD officials told us that they plan to work with the military services to collect any analyses completed that may show how changes in requirements can lead to cost reductions. Until we are able to review and assess these analyses, this recommendation will remain open.
Department of Defense The Secretary of Defense should ensure that, prior to the Milestone C decision, the Under Secretary of Defense for Acquisition and Sustainment, in consultation with the services and the F-35 Joint Program Office, develop and document a program-wide plan for achieving affordability constraints with detailed actions tied to milestones and resources. (Recommendation 3)
Open
DOD agreed with the substance of the recommendation and is currently taking actions to address the recommendation. As of February 2023, DOD officials told us that the F-35 Joint Program Office is using specific activities, including Plan of Actions and Milestones, to drive affordability cost reduction efforts. These activities will also include timelines, resource requirements, assumptions, and risks against the current military service-provided affordability constraints. DOD plans to document all of these efforts in an update to the F-35's Life Cycle Sustainment Plan; however, the completion date of this update is undetermined. Until we are able to review and assess the updated F-35 Life Cycle Sustainment Plan and determine the extent to which DOD has developed a program-wide plan for achieving its affordability constraints, this recommendation will remain open.
Department of Defense The Secretary of Defense should ensure that, prior to the Milestone C decision, the Under Secretary of Defense for Acquisition and Sustainment, in consultation with the services and the F-35 Joint Program Office, develop and document a risk-management approach for addressing potential challenges or making adjustments in order to achieve affordability objectives. (Recommendation 4)
Open
DOD agreed with the substance of the recommendation. According to DOD officials, the F-35 program will incorporate cost risk mitigation plans into its overall risk mitigation strategy once the military services finalize and document their updated steady-state affordability constraints. A completion date for the updated steady-state affordability constraints could not be determined. Until these actions are taken and a risk-management approach has been developed and documented, this recommendation will remain open.

Full Report

GAO Contacts