night. there are so many different moving parts and the temperature variants from hot to cold. there are things like metal fatigue. what we ve heard so far there is a fan blade messing from this. it could have been in a compressor turbin section. if you look at fan on the ceiling spinning. imagine it spinning at 30,000 rpm. really fast. you take off one blade of that fan and stick it up in the fan it will cause parts to rip apart and in an engine like this you have fuel being dumped in so you are probably getting compressor stalls and getting pop and hung stalls and explosive action that can cause the pieces to rip off the plane. most likely she probably felt a bang, her and her first officer probably felt a bang and heard something. then all of a sudden they get the indications in the cockpit they ve lost pressure and think first off have to make sure we re breathing. second get down below.