As the completion of the F-35 development program is nearing towards the end in 2019, a new stream of criticism by the United States Congress points at multiple flaws found so far which were not yet addressed, and is reluctant on allocating more funds for a modernization program.

The U.S. Defense Department office responsible for the F-35 program is expected to take a decision on full-rate production of the aircraft by October 2019 - an official deadline for the development program. However, 180 of the 966 “open deficiencies” reported during tests - mainly concerning avionics software - will not be fixed by that time.

The United States Congress committee known as the Government Accountability Office (GAO) issued a report where it criticizes the decision of the Defense Department to give its answer on full production before critical flaws are fixed.

The report states that “the program office plans to resolve a number of critical deficiencies after full-rate production. Resolving these deficiencies outside of the developmental program may contribute to additional concurrency costs, which also carries affordability implications.”

The congressional committee recommends that the Pentagon does not sign contracts for large F-35 procurements by the U.S. Air and Naval Forces before the reported glitches are addressed. According to the GAO report, the Department of Defense agrees on the recommendation and “would resolve all critical deficiencies before its full-rate production decision.”

The GAO also questions the recent request from the development office for funding a Block 4 modernization program called C2D2. If the Congress recognized it could “potentially shorten time frames for delivering capabilities over a traditional acquisition approach”, it reproves the lack of transparency that would ensue if a precise financial assessment was not conducted first. Such a report will not be issued by the Department of Defense before March 2019.

On March 7, 2018, Vice Admiral Mathias Winter, the executive officer of the F-35 program, reported that the update of the fighter between 2018 and 2024 would cost approximately $1 billion per year. The total cost of the program was already estimated at $1.1 trillion, according to the last Pentagon overview.