WASHINGTON — An issue that risks damage to the F-35’s tail section if the aircraft needs to maintain supersonic speeds is not worth fixing and will instead be addressed by changing the operating parameters, the F-35 Joint Program Office told Defense News in a statement Friday.

The deficiency, first reported by Defense News in 2019, means that at extremely high altitudes, the U.S. Navy’s and Marine Corps’ versions of the F-35 jet can only fly at supersonic speeds for short bursts of time before there is a risk of structural damage and loss of stealth capability.

The problem may make it impossible for the Navy’s F-35C to conduct supersonic intercepts.

“This issue was closed on December 17, 2019 with no further actions and concurrence from the U.S. services,” the F-35 JPO statement read. “The [deficiency report] was closed under the category of ‘no plan to correct,’ which is used by the F-35 team when the operator value provided by a complete fix does not justify the estimated cost of that fix.

“In this case, the solution would require a lengthy development and flight testing of a material coating that can tolerate the flight environment for unlimited time while satisfying the weight and other requirements of a control surface. Instead, the issue is being addressed procedurally by imposing a time limit on high-speed flight.”The carrier-launched "C" variant and the short-takeoff-and-vertical-landing "B" version will both be able to carry out all their missions without correcting the deficiency, the JPO said.

The potential damage from sustained high speeds would influence not only the F-35’s airframe and the low-observable coating that keeps it stealthy, but also the myriad antennas located on the back of the plane that are currently vulnerable to damage, according to documents exclusively obtained by Defense News.The JPO had classified the issues for the "B" and "C" models as separate category 1 deficiencies, indicating in one document that the problem presents a challenge to accomplishing one of the key missions of the fighter jet. In this scale, category 1 represents the most serious type of deficiency.

While it may seem dire that an aircraft procured for flying at supersonic speeds will be unable to do so for extended periods, the F-35 may not need to do it that often.

For the F-35, as opposed to the F-22 where supersonic flight is baked into its tactics, the ability to fly supersonic is more of a “break glass in case of emergency” feature, said Bryan Clark, an analyst with the Hudson Institute and a retired naval officer.