Lockheed Martin and the F-35 joint program office have developed a solution to the insulation problem that temporarily grounded 15 F-35A aircraft in September, according to a joint program office statement. The repairs are focused on “non-compliant Polyalphaolefin coolant tubes,” which were deteriorating and leaving debris in the fuel lines and fuel tank. The repair takes about three weeks to complete, the statement said, and is being performed on 42 in-production aircraft in addition to the 15 that were grounded. The grounded aircraft will return to flight, and the new aircraft will be delivered, by the end of the year, according to Lockheed Martin. Included among the new F-35As are the first deliveries to Israel and Japan. “This was not a technical or design issue, “ the statement said, “it was a supply chain manufacturing issue.” (See also Jets May Fly With F-35 Fuel Issue.)
Dirty hydraulic fluid and freezing weather led to the loss of an F-35 stealth fighter in Alaska this winter when its landing gear froze and convinced the aircraft’s computer that it was on the ground rather than in-flight.