The U.S. Air Force fleet of some 376 F-35A fifth-generation fighters is back in the air after problems with ejection seats, reported by AVweb two weeks ago, grounded them. According to an email from USAF Air Combat Command spokeswoman Alexi Worley to Defense News, technicians checked 706 ejection-seat cartridges from 349 USAF F-35s, along with spares. Four were replaced due to potential problems.
A small number of the fighters remain to be checked, but since they are already undergoing 90-day inspections, their ejection seats will be reviewed as part of the normal inspection protocol.
An alert technician at Hill Air Force Base in Utah in April discovered a loose cartridge with its magnesium charge missing. Inspections of several other F-35s led to the conclusion it was an isolated incident and the stealth fighters were allowed to return to operations.
But ejection-seat manufacturer Martin-Baker checked its components inventory and uncovered two additional defective cartridges in April. A quality check revealed that its production process was creating the defective cartridges and the F-35 Joint Program Office ordered an inspection of all ejection seats within 90 days.
