So now we have a possible scenario of why the Epicyclic blew apart.
I always maintained a Sus Bar or Foot will not cause the Gearbox to separate.
But I also don't see the Planet wear causing the event. It became a weak point for sure. If the Sus Bar letting go did cause enough gear stress for the Epicyclic to fail is really doesn't matter does it......EITHER scenario on it's own or together will result in total destruction of the Machine and everyone in it.
What can't be ignored regardless of what the cause, is the fact it was never detected by HUMS, CHIPS, FDR, CVR, SOAP, ENGINEERS, PILOTS
Whatever failed first it gave no warning at all!
Why the Gear Race wear was not picked up in a SOAP sample, is also a mystery. Surely SOAP samples are taken as part of the normal Maintenance Program.
HUMS is clearly inadequate in detecting detecting early bearing wear issues in the Epicyclic. With multiple Gears with the same tooth count rotating on the same plane it's not doesn't surprise. A Tooth defect is a different story.
I'm sure the HUMS actual values, learning values, component step change, ETC were all looked at in great detail. You might find now they know which component is worn they can take another closer look at the HUMS Data and actually spot the wear. If if they did,was the Relevant Data significantly above the Noise to fix by reducing the trigger levels on the those Accelerometers. I think not.
If the Conical housing failed then surely that can only happen if it was badly treated at some stage, same could be said for the Sus Bars or Gearbox itself.
The speed of the occurrence with no warning remains the most disturbing thing whatever the finding and it's getting harder and harder to walk away from