Cost of F-35 Fighters Program to Hit $400 Billion

America’s most expensive weapons’ program ever just got more expensive, according to a Government Accountability Office report.

The report states that the Pentagon needs to spend $316 billion between now and the end of 2037 to finish developing its Lockheed Martin Corp F-35 fighters program.

The figure equates to $12.6 billion each year and is $2 billion more a year than originally projected in the GAO’s draft report.

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Joe DellaVedova, a spokesman for the Pentagon's F-35 program office, said the draft report did not include the cost of the jet fighter’s engine, Reuters reports.

In its updated, annual report to Congress on the F-35, the GAO said the final, full cost of the program will be about $400 billion, adding: "Overall, the F-35 Joint Strike Fighter program is now moving in the right direction after a long, expensive, and arduous learning process. It still has tremendous challenges ahead."

The radar-evading F-35 is expected to serve the U.S. Air Force, Navy and Marines for many years to come. The program has so far been dogged by technical difficulties and costs have soared 70 percent from initial projections.

Air Force Lieutenant General Christopher Bogdan, who oversees the F-35 program, said: "We have more work to do and we're committed to delivering on the promise of the F-35; it will form the backbone of U.S. air combat superiority for generations to come."

The Pentagon plans to buy 2,443 warplanes and estimates it will cost over $1 trillion for the cost of operating and maintaining them throughout an estimated lifespan of 30 years.

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But for the GAO, the dollar amount remains the bottom line. The report said: "The Department of Defense and the contractor now need to demonstrate that the F-35 program can effectively perform against cost and schedule targets in the new baseline and deliver on promises.

"Achieving affordability in annual funding requirements, aircraft unit prices, and life-cycle operating and support costs will in large part determine how many aircraft the U.S. military can have."