The Defense Department is one of the largest line items in the federal budget. Hundreds of billions of dollars each year are devoted to sustaining and maintaining our armed forces, as one would expect.

But billions more are spent developing new systems to address new threats. One of those systems is the F-35 fighter. Long in development, and even longer in turmoil, the F-35 program has become a symbol of problematic defense spending…and the Government Accountability Office says the program needs serious fiscal restraint if it’s to be at all viable:

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… The services will collectively be confronted with tens of billions of dollars in sustainment costs that they project as unaffordable during the program.

These aren’t cuts at the edges:

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 (bolding added).

It’s not uncommon for government to pour money into a program where costs override benefits and sustainability is impossible. The F-35 will become one of those programs unless Congress acts to prevent it. A tall order for the current lot, indeed…but critical for the health of the armed services, and Uncle Sam’s bottom line.