Does anyone have access to the Investigation report as I can't find it?
Blackhand, the prelim report has been finalised but not released publicly yet, it will be shortly.
In the meantime please refer to my below post, you will find out in due course that this sums up accurately the invstigation thus far, limited in scope and detail, but the guts of the investigation so far are as I have posted.
At 1717 the aircrafts overspeed warning sounded. Very shortly afterwards BOTH props simultaneously oversped and exceeded their maximum rpm by in excess of 60%.
Witnesses on the ground reported hearing a loud 'bang' as this occurred. The flight crew shut down both engines.
Preliminary CVR transcript, sound spectrum plot, FDR plots and data listings have been supplied to the investigative team.
Ongoing investigation activities are continuing in the area of engine and prop assemblies, recorded information and maintenance documentation and procedures.
A reliable source has advised me that the loud bang heard by the eyewitnesses was likely the blade tips cracking the sound barrier. This would match up with the excess overspeed, but is
only speculation at this point.