Known ,extremely infrequent occurrence with RR engine.
Problem with the T/R inner wall lining due long term exposure to elevated temperatures.
Typically occurs during takeoff or shortly after rotation. Loud bang or jolt and EICAS messages + increased fuel flow on affected engine.
Service bulletins 777-78-0071 and 777-75A0002 deals.
Release of parts of engine primary nozzle,aft cowl and portions of the inner wall can lead to minor airplane damage to tires,stab,flaperons,wing control surfaces and wing lower surface.
Continued flight after the T/R failure increases the risk of continued parts liberation from the affected engine....Flight crews should be aware of fuel management given the potential increased fuel consumption resulting from the T/R failure. Thrust reverser should not be selected on subsequent landing if damage is suspected.
A turnback would be understandable, given the prudent nature of most crews, but it is a crew decision, taken in conjunction with maintenance control.
