CNN - Malaysia Airlines Flight 370: How do passenger jets change flight paths?

(CNN) -- The timing of Malaysia Airlines Flight 370's change of direction is a focal point of the investigation into its disappearance, and it appears the passenger jet was programmed to steer off course before the pilots signed off with air traffic control -- and that the change of course was transmitted to air traffic controllers.

The flight's Aircraft Communications Addressing and Reporting System communicates various data to the ground, including engine reports, maintenance requirements and weather conditions.

The last transmission from Flight 370's ACARS system came at 1:07 a.m.

The next update was due at 1:37 a.m. It never came.

While all information so far indicates that someone inside the cockpit, believed to be the co-pilot, made the last verbal communication with air traffic controllers -- "All right, good night" -- at 1:19 a.m., a law enforcement official told CNN that the plane's programmed change in direction was entered at least 12 minutes before the plane's verbal sign-off...

See more here: CNN - Malaysia Airlines Flight Path Change