The Pentagon on Friday grounded its fleet of F-35 fighter jets after discovering a cracked engine blade in one plane.
The problem was discovered during what the Pentagon called a routine inspection at Edwards Air Force Base, California, of an F-35A, the US Air Force version of the sleek new plane.
The US Navy and the US Marine Corps are buying other versions of the F-35, which is intended to replace older fighters like the F-16 and the F/A-18.
All versions — a total of 51 planes — were grounded on Friday pending a more in-depth evaluation of the problem discovered at Edwards.
In a brief written statement, the Pentagon said it is too early to know the full impact of the newly discovered problem.
A watchdog group, the Project on Government Oversight, said the grounding is not likely to mean a significant delay in the effort to field the stealthy aircraft.
“The F-35 is a huge problem because of its growing, already unaffordable, cost and its gigantically disappointing performance,” the group’s Winslow Wheeler said.
The F-35 is the Pentagon’s most expensive weapons program at an estimated cost of nearly US$400 billion. The Pentagon envisions buying more than 2,400 F-35s, but some members of US Congress are balking at the price tag.
Friday’s suspension of flight operations will remain in effect until an investigation determines the problem’s root cause.