The pilot sent a manual signal at 11 p.m. local time saying he was flying through an area of "CBs" — black, electrically charged cumulonimbus clouds that come with violent winds and lightning. Satellite data has shown that towering thunderheads were sending 100 mph (160 kph) updraft winds into the jet's flight path at the time.
Ten minutes later, a cascade of problems began: Automatic messages indicate the autopilot had disengaged, a key computer system switched to alternative power, and controls needed to keep the plane stable had been damaged. An alarm sounded indicating the deterioration of flight systems.
Three minutes after that, more automatic messages reported the failure of systems to monitor air speed, altitude and direction. Control of the main flight computer and wing spoilers failed as well.
The last automatic message, at 11:14 p.m., signaled loss of cabin pressure and complete electrical failure — catastrophic events in a plane that was likely already plunging toward the ocean.