A new report reveals a communications system on that missing Malaysian plane shut down before one of the pilots communicated with the tower.
It's the latest evidence of foul play and it comes as investigators search the flight simulator found in one of the pilot's homes.
Malaysian authorities have offered contradictory information on the timeline of events, which a U.S. official said is an effort to keep things secret.
Background checks of all Chinese citizens onboard the aircraft found no links to terrorism, ruling out speculation that Chinese Muslim separatists might have been involved in the plane's disappearance.
Still, all signs point to a deliberate act.
"With the turns this airplane made, even if we don't know the altitudes, someone was very definitely in control of this airplane and knew what they were doing," aviation consultant John Nance said.
Hijacking still hasn't been ruled out.
Meanwhile, almost two weeks later, there are still few leads on the plane's location.