美空军停飞F35

US Air Force grounds F-35 fighter jets

Washington (CNN)The US Air Force said Friday it has grounded 10 of its F-35 Joint Strike Fighters, just over a month after they were declared "combat ready."

The decision affecting the most expensive weapons system ever was made "due to the discovery of peeling and crumbling insulation in avionics cooling lines inside the fuel tanks," the Air Force said in a statement, describing the action as a temporary pause in flight operations."