WASHINGTON — Testing delays will push a decision on whether to move the F-35 to full-rate production into late fiscal 2023 — and perhaps into fiscal 2024.

In a roundtable with reporters Tuesday, Lt. Gen. Eric Fick, the program executive officer for the F-35 Joint Program Office, said the F-35′s critical Joint Simulation Environment testing, which has to happen before the aircraft’s initial operational test and evaluation phase can be closed, is now expected to take place in early spring or summer 2023.

Before a milestone C decision can be reached on full-rate production for the F-35, the results of these simulation tests must be validated and used to help create a report necessary for the review.

Asked whether the tight time schedule effectively makes impossible a decision on full-rate production in fiscal 2023, Fick said, “I don’t think it rules it out.”

“But in the event that our [testing was] to slip by any appreciable margin, there’s not a lot of leeway between the end of the summer, the generation of the report, and the ability to have a milestone [C] decision,” he said.

The Defense Department originally planned for a full-rate production decision for the F-35 in December 2019, but it has repeatedly slipped due to Joint Simulation Environment delays.

The Joint Simulation Environment will create high-end threat scenarios to test how well the F-35 will respond in the most dangerous situations. The scenarios the F-35 will face will include varying threat densities, different mixes of aircraft and a variety of ground threats in the simulations, including possible threats the fighter could face in the future, Fick said.

Fick said the Defense Department is “aggressively” working through the validation, verification and accreditation of the simulation’s components. About half of the 88 packages necessary for this step have been completed, he said, and the program hopes to have that done around May 2022.

Once that is done, Fick said, the program moves into system validation verification — bringing components together into broader scenarios for their own validation, verification and accreditation. That is expected be done by this September, he said.

The weeks long testing period, in which 64 test events will be run, will follow next year.

Fick said although the JSE has not been completed yet, “we’re very confident” in the F-35′s ability to fight if it had to engage in combat in Europe.

F-35s already deployed overseas — including six from the 34th Fighter Squadron from Hill Air Force Base in Utah, which deployed to the eastern flank of NATO after Russia’s invasion of Ukraine — have the most up-to-date mission data files they need for combat, he said.

“The JSE is a tool … to verify the F-35′s performance against a series of threats that we can’t get to in the open air, short of actual combat,” Fick said. “We understand the threats that the F-35 is going up against today. We understand the threats largely propagated throughout Europe, and those were the threats that the airplane was developed to counter.”

Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.

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