The failure of two GEnx engines this summer and the discovery of a crack in the midshaft of another engine has prompted the National Transportation Safety Board to recommend to ground Boeing jetliners equipped with those engines until they can be inspected.
The new engines are installed on some Boeing 787 Dreamliners and on all Boeing 747-8 aircraft.
Boeing and GE said today all passenger aircraft equipped with those engines have been inspected. Some 747-8 freighters with GE engines remain to be inspected.
The NTSB’s recommendation went to the Federal Aviation Administration, which can order the inspections.
The safety board further recommended that the FAA order frequent re-inspections of those GE engines until the manufacturer finds the sources of the cracking and corrects it.
One GEnx-1B failed on an Air India 787 which was undergoing ground testing in July in Charleston, S.C. Parts of that engine’s low-pressure turbine were ejected from the engine and started a grass fire near the runway.
Another Boeing plane, an Air Bridge Cargo 747-8 equipped with GEnx-2b engines, experienced an engine failure on its takeoff roll from Shanghai last week. The failure occurred as the plane was moving down the runway at about 50 mph. The captain halted the takeoff roll when the problem was detected. The engine’s midshaft had fractured causing failure of the low-pressure turbine. Both failures were contained within the engine.
GE and Boeing along with the NTSB have been analyzing the failures.
“As a result of the investigative work to date, the NTSB has determined that the fan midshafts on the GEnx engines fractured or cracked at the forward end of the shaft where the retaining nut is installed,” the safety agency said.