On 29 November 2013, an Embraer 190 Captain intentionally initiated a high speed descent from the previously-established FL380 cruise altitude after the First Officer left the flight deck and thereafter prevented him from re-entering. The descent was maintained to ground impact with the AP engaged using a final selected altitude below ground level. The Investigation noted that the Captain had been through some “life experiences capable of having an effect on his state of mind but in the absence of any other evidence was unable establish any motive for suicide.