The United States government has allowed the delivery resumption of the Pratt & Whitney F135 engine that powers the Lockheed Martin F-35 Lightning II fighter jet. Its deliveries were halted in December 2022, after an F-35B crash in Texas, the US, and the subsequent discovery of a safety concern.
On December 15, 2022, an F-35B fighter was attempting to land vertically at the Fort Worth air base when it bounced off the runway. The aircraft’s nose pitched down and the nose gear collapsed, sending the jet sliding forward and spinning slowly. The pilot ejected from the fighter.
The F-35B is the short takeoff and vertical landing (STOVL) variant of the aircraft.
Following the incident, the US authorities grounded a number of F-35 fighters while a crash in Texas was being investigated. The F-35 Join Program Office (JPO), which oversees the F-35 deliveries, explained in a statement at the time that the grounding affected the aircraft that were “evaluated to be of higher risk” and the decision was put into effect until “procedures can be developed for their return to flight”.
It later became known that some F135 engines that powered the aircraft were affected by a “rare system phenomenon involving harmonic resonance”, as Pratt & Whitney vice president Jen Latka explained earlier in February 2023.
Now, the JPO says a solution has been found that can clear the way for affected F-35s to return to service, according to the organization’s statement on February 24, 2023.
The JPO said that a team of government and industry experts is working on implementing “mitigations for a rare system phenomenon involving harmonic resonance to develop a path forward for safe operation of the F135 in flight”, according to a written statement seen by Reuters.
“The government is currently working to provide instructions to the fleet and to Lockheed Martin to enable safe resumption of flight operations of impacted aircraft and new production aircraft”, the statement also outlined.