The US Federal Aviation Administration (FAA) has issued an “urgent safety issue”, alert over engines on some B787 Dreamliners, because an icing problem could force those engines to shut down in flight – a potentially disastrous situation.
The specific engine type is the General Electric (GE) GEnx-1B PIP2 and the order affects about 176 Dreamliners at 29 airlines worldwide, the FAA document said.
Qantas has chosen General Electric (GE) GEnx engines to power its Boeing 787-9 fleet but the planes will not start to arrive until 2017, when the problem will long since have been fixed.
Jetstar has 11 B787s in its fleet, powered by General Electric GEnx-1B64 engines, according to its website.
Scoot operates an all-B787 fleet but uses another engine type altogether, the Rolls-Royce Trent 1000. Air New Zealand, another B787 customer, also uses the Rolls-Royce Trent 1000.
Friday’s FAA airworthiness directive stems from a January 29 incident aboard a B787 flying at about 20,000 feet.
The FAA document states: “The urgency of this issue stems from the safety concern over continued safe flight and landing for airplanes that are powered by two GEnx-1B PIP2 engines operating in a similar environment to the event airplane. In this case both GEnx-1B PIP2 engines may be similarly damaged and unable to be restarted in flight. The potential for common cause failure of both engines in flight is an urgent safety issue.”
The B787 Dreamliner has two engines.
The FAA directive adds: “Susceptibility to heavy fan blade rubs, if not corrected, could result in engine damage and a possible in-flight non-restartable power loss of one or both engines.”
In some cases, planes could be grounded to fix the problem, the FAA directive said.
“Recognizing the urgency of this safety issue, this AD [airworthiness directive] represents a compressed schedule to rework a large number of airplanes located around the world. Both specialized tooling and trained personnel are required on-site to perform the rework at various maintenance facilities around the world. To complete the work, 29 airlines will need to reallocate 176 airplanes from revenue service to maintenance in order to conduct the (on-wing) rework. The FAA has determined that 150 days is the minimum time to rework one engine per airplane on the entire fleet.”
General Electric told CNN it was “working with operators to avoid airline disruption,” adding that the rectification process “takes about 16 hours using a fan grinding machine. All of the work is done on-wing with no engine removals”.
For pilots who are flying 787s that haven’t undergone the fix, the FAA has ordered an in-flight ice removal procedure.
Whenever pilots suspect ice buildup above 12,500 feet – or when the indicator light confirms it – pilots are advised to rev each engine at 85% of full throttle every five minutes, CNN reported.
FAA airworthiness directives about such matters are not uncommon.
Written by Peter Needham