According to USNI News, Lockheed and the JPO found cracks on three of six aluminum wing carry-through bulkheads on a ground structural test article.
“Because of the high hours accumulated on this test article, this discovery does not affect current F-35B flying operations,” Lockheed and the JPO said in a joint statement. “Nor is it expected to impact the U.S. Marine Corps’ ability to meet its Initial Operating Capability (IOC) in 2015.”
As USNI News points out, the Marine Corps F-35B will still meet its IOC date because the test article had already amassed 9,480 hours of flight time when the probably was discovered.
“9,480 durability test hours equate to more than 17 years of operational flying,” the statement reads.
The F-35 must have an airframe life of 8,000 flight hours, which is verified via durability testing through two structural lifetimes.
“The purpose of durability testing is to intentionally stress the aircraft to its structural limits so we can identify any issues and corrective actions needed to fix them,” the joint statement reads. “These discoveries are expected and planned for in a developmental program.”