S14E6: Killer in the Cockpit?

A 737 cruising above an Indonesian jungle suddenly plummets from the sky. An Airbus A320 crashes into the French Alps. Malaysia Airlines Flight 370 vanishes over the Gulf of Thailand. At first, these accidents perplex investigators, until surprising findings suggest the pilots could be to blame. See how these acts forced the industry to be more proactive in monitoring the mental health of their pilots.