A bit more on the FAA and the problem on GE Engines
FAA orders urgent fix to engines that could shut down on Boeing 787s | The Seattle Times
The FAA directive, first reported Friday by The Wall Street Journal, states that the problem arises only in the latest upgraded model of the GEnx engine powering the Dreamliner, the GEnx-1B PIP2.
That upgrade, which was certified by the FAA and entered service in 2013, improved the fuel burn incrementally, in part by reducing the tiny gap between the tips of the engine’s large fan blades and the fan case.
In the January incident, ice had built up on the fan blades before the trouble occurred at an altitude of 20,000 feet as the plane descended.
When the ice abruptly shed, it caused the blades to move slightly forward and because of the contour of the fan case, this was enough to make the blade tips rub against the case.
The resultant heavy vibrations did so much damage that the engine shut down and could not be restarted.
Luckily, the GEnx engine on the other wing of the JAL Dreamliner was older and not the specific upgraded PIP2 design. The FAA directive says that second engine incurred only “minor damage during the icing event and continued to operate normally.”
A side note. Many many years ago when the 787 was just starting preliminary design and concepts, the management was beginning to look for the cheapest way to do things with minimum $$$$$ outof pocket. A very logical ' beancounter' power point ranger had prettty well sold the idea of a choice of a Single engine manufacturer via competition, yada yada. A very good friend of mine who was well respected in the company despite being a ' simple' Engineer albeit with many hours of military and commercial flight, delivery, and training hours going back to Kc-135 tankers made his views on that
very well known- that it was to big a risk for a variety of reasons.
Suggested that two engines be chosen from the then 3 major manufacturers- and that a common interface/mounting be designed so it would be a near plug and play issue.
As a senior official later said about him -" We never had a problem diagramming his sentences "
And so it goes . . .