Washington: The US military and defence contractor Pratt & Whitney has suspended deliveries of new engines for the F-35 fighter in the wake of a December mishap on a Texas runway.
The F-35 Joint Program Office (JPO) said in an email to a media that the delivery of new F-35 engines was paused December 27, after what the JPO described as a “mutual agreement” involving itself, the Defence Contract Management Agency and engine-maker Pratt & Whitney.
The JPO said that deliveries are paused while the investigation into the December 15 mishap involving an F-35B continues, and as ground tests take place to identify the root cause of the accident.
“The F-35 Joint Program Office and Pratt & Whitney have agreed to delay scheduled delivery and acceptance of F 35 engines until further information from the investigation is known and safety of flight can be ensured,” the JPO said in a follow-up email.
A Pratt & Whitney executive said in a statement that F-35 deliveries were not formally suspended. The company did not immediately respond to a request to clarify its statement.
“There has been no formal suspension of F-35 deliveries and we are working closely with the Joint Program Office on all aspects of the ongoing investigation and timing of deliveries,” said Jen Latka, vice president of F-35 programs at Pratt & Whitney. “The F-35 has more than 600,000 flight hours. Safety for the warfighter is and will continue to be our number one priority.”
Video of that incident at Naval Air Station Joint Reserve Base Fort Worth showed the newly constructed F-35B hovering close to the ground before descending. The fighter bounced once and tipped forward; its nose and wing touched the ground as it started to spin around. The fighter’s Air Force pilot, who was performing a quality check flight for the Defence Contract Management Agency, safely ejected on the ground.
After that accident, Lockheed Martin, which makes the jet, halted acceptance flights of new F-35s at all three of its production facilities, including Air Force Plant 4 in Fort Worth. This had the effect of also halting deliveries for the last two weeks of the year, which meant Lockheed delivered 141 F-35s in 2022, fewer than the contractually required 148.
Lockheed said on December 30 it was on track to meet its delivery commitments before the mishap, and has continued to build F-35s. The company said it had nine completed fighters ready to undergo acceptance flights.
The JPO said in a statement last week it had issued guidance restricting some higher-risk aircraft from flight operations while the investigation continued. The JPO later revised its statement to say it had recommended the flight operation restrictions until procedures are developed for their return to flight.
According to a media report, the initial investigation into the December 15 mishap, conducted by Naval Air Systems Command with JPO’s support, found a tube used to transfer high-pressure fuel in the fighter’s engine had failed. This discovery prompted the JPO to update its safety risk assessments for a small number of fighters.
The JPO said it is working with DCMA, Pratt & Whitney, and Lockheed Martin to develop procedures to lift the restrictions and resume acceptance flight operations, but doesn’t know how long the groundings will be in effect.