Following a notice of proposed rulemaking published last September, the FAA issued an airworthiness directive (AD) mandating shorter life limits for certain Rolls-Royce AE 3007A and 3007C model turbofan engine fan wheels. It was thereafter promptly adopted by EASA.
The directive was prompted by manufacturer tests that revealed “higher stress than previously calculated in the aft retainer flange scallop of the fan wheel, part number 23061670.” As a result, Rolls-Royce issued Alert Service Bulletin AE 3007A-A-72-424/ASB AE 3007C-A-72-327, reducing the life of the fan wheel.
After consideration of the lone comment submitted in support of the rulemaking, by the Air Line Pilots Association, the agency issued the final rule, mandating removal of the affected fan before exceeding new life limits.
The agency estimates that the rulemaking affects 341 U.S.-registered aircraft engines and will cost industry $4.2 million in replacement parts.
The vast majority of AE 3007A engines power the twin-engine Embraer 145 series regional jets. The AD took effect on Jan. 31.