The U.S. FAA issued an emergency AD, requiring operators to perform thermal acoustic image (TAI) inspections of the 1st-stage low-pressure compressor blades on PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan engines, before further flight.
This action was taken in response to the Feb. 20 engine failure of United Airlines flight 328, a Boeing 777-200 aircraft.
Tags: B772