The aircraft and its parts aren’t as reliable as expected, and it’s taking longer to repair them than planned, according to the presentation by the director of operational testing for defense officials and congressional aides. About 20 percent of the jets must await spares in depots because suppliers can’t keep up with expanding production while fixing returned parts.
Costs and delays mean it is projected to cost $379 billion program to buy the planned fleet of 2,443 fighters for the Air Force, Navy and Marine Corps.
Repair and maintenance trends mean long-term “lifecycle costs” of the aircraft are “likely to increase significantly” over the current $1.2 trillion estimate and affect budgets of the services, according to the presentation, which updated the testing office’s annual report released in January.
The fleetwide availability of F-35s to fly when needed is 52 percent, short of an interim goal of 60 percent as well as the 80 percent needed to start combat testing next year.
Lieutenant Colonel Roger Cabiness, spokesman for the testing office, said the issues cited in the May 8 presentation persist, although some of the specific numbers cited have changed “as the program continues to work fixes and discovers new deficiencies” during the $55 billion development phase that’s scheduled to end early next year.
One key metric is the average number of flight hours between critical failures, those that could render an aircraft unsafe to fly or unable to complete its mission. The goal for the Air Force’s F-35 is 20 hours between failures after 75,000 hours of flight. As of August, Air Force models were averaging only 7.3 hours between failures after 34,197 hours of flight, according to the testing office presentation.