The high pressure compressor case may not be capable of containing even 7-8 inch long pieces of the disk at near maximum RPM conditions. FAR requirements address blades and not rotors (standard and possibly integrated rotor). I can see a fuel line outside the effectiveness of the engine fire extinguishing system being breached by expulsion of these fragments through the case.
While not a commercial engine guy, just a military engine designer with some extensive knowledge of the adverse effects of ballistic impact on turbine engines, this is just an opinion.
Last edited by flyguyfl; 11th Sep 2015 at 01:53.