15 F-35 Models Grounded Due to Wiring Issue

The US Air Force has ordered the grounding of 13 F-35A models, as well as a pair of Norwegian F-35As, following the discovery of "peeling and crumbling" coolant tube insulation.
The issue appears to have been with a supplier of coolant lines, which are installed in the wings of the jet. During a routine maintenance check, it was discovered that the insulation on the lines were in some cases decomposing, which left residue in the fuel itself, according to a release from the Norwegian government on the grounding.
The issue has been traced back to the insulated coolant tubes manufactured by one particular provider that have only been installed in the wing fuel tanks of the 15 aircraft — 10 from Hill Air Force Base, Utah, two US and two Norwegian F-35As at Luke AFB, Ariz., and one plane at Nellis AFB, Nev.
The problem was first discovered this summer during depot maintenance of an F-35A being prepared for initial operational capability.
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