F-35 og F135 motoren

Half-inch crack blamed for F-35 fighter jet grounding: sources



WASHINGTON (Reuters) - The engine blade crack that prompted the U.S. military to ground all 51 F-35 fighter jets was over half an inch long, according to three sources familiar with the matter, but it remained unclear if the crack was caused by a manufacturing anomaly or some larger design issue.

Engineers at Pratt & Whitney, a unit of United Technologies Corp, will conduct a detailed examination of the turbine blade as soon as it arrives at the company's Middletown, Connecticut, site, said spokesman Matthew Bates.

"Pilot safety is our absolute top priority," Bates said, noting that the F135 engine that powers the new radar-evading fighter jet had a readiness rate of over 98 percent.
"We are in a testing phase of the program and discoveries such as this are part of the process," he added.

Initial results may come on Wednesday, although it could take up to 10 days to complete the analysis, said the three sources, who were not authorized to speak publicly.

The Pentagon announced the grounding of all F-35 warplanes on Friday after an inspection revealed a crack on a turbine blade in the Pratt-built jet engine of an F-35 jet being tested at Edwards Air Force Base in California.

It was the second engine-related grounding of the $396 billion F-35 Joint Strike Fighter in two months, and came on the eve of a big air show in Australia, which is considering reducing its planned purchase of 100 F-35 jets.