Engine shaft sheared allowing the complete LPT assy to move aft.......and out
.
IIRC sheared at the end of the thread where the coupling nut is!
Same thing happened to a 744 with CF6-80's recently too......must be a GE thing.
And the AC 773 GE90-115 was a failure in the HPT section...hence the
bang!
That was an HPT stage one shroud departing company taking everything aft with it!
