Recurring problem due to the engine running 190F hotter than planned? There is history...
Joint Strike Fighter F135 Engine Burns Hotter Than Desired
F-35 Report: overview of problems with F-135 engine
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Conclusion
The repeated problems with the same part of the engine may be indications of a serious design and structural problem with the F-135 engine.
A future F-35 fleetwide grounding will paralyze the Western Airpower. Also, the lack of reliability will contribute to low service ability and to high operating and support costs of the F-35 fleets in several countries putting more pressure on the low defence budgets.
Since the F-35 will be the cornerstone of the NATO airpower and US homeland defence the next decades, the problems with the F135 engine need attention of the highest political decision makers.