The Air Force announced on Friday it was grounding 15 F-35As, including 10 operational jets, due to a problem in avionics cooling lines caused by a subcontractor. The issue, which was first identified in early September about one month after the service declared its F-35A fleet operational, also impacts 42 aircraft on the production line. Of the 15 grounded F-35As, 10 are operational planes at Hill AFB, Utah; two are training jets at Luke AFB, Ariz.; and one is a test plane at Nellis AFB, Nev., Air Force spokeswoman Ann Stefanek told Air Force Magazine. In addition, two Royal Norwegian Air Force jets have been grounded. The issue stems from a subcontractor incorrectly installing avionics cooling lines in the wings of the jets, which can cause insulation — Poly-Alpha-Olefin — from the lines to come off and potentially enter fuel. The issue was discovered in depot maintenance at the Ogden Air Logistics Center, Lockheed Martin said in a statement. “This is not a technical or design issue, it is a supply chain manufacturing quality issue,” Lockheed said. “It will likely require depot-level maintenance to address the corrective actions for the 15 jets in the field.” There is no timeline for when the jets will return to flight, though possible mitigation plans could begin next week.” The issue is from one unnamed subcontractor not installing correctly, and only impacts part of the 104 operational F-35As, the Joint Program Office said in a statement. The Norwegian Ministry of Defense said in a statement that its two affected jets are at the Partner Training Center at Luke, it Norwegian authorities decided to suspend operations on the planes. Norway plans to buy up to 52 of the aircraft, and expects the problem to be fixed by the time it receives its next F-35A.
U.S. Air Force F-35s and F-22s regularly deploy deep into the Pacific region from Alaska, Utah, and Hawaii. In the future, though, the head of U.S. Indo-Pacific Command would like to see the Air Force permanently station fifth-generation aircraft west of the international date line—closer to China.