Has there ever been a fully automated takeoff, cruise, and landing of a large aircraft similar to commercial airliners?
The book The Glass Cage describes a fully autopilot-controlled military test flight in 1947. The plane was a C-54 Skymaster with seven men aboard. According to this source, the pilot aligned the plane on the runway for takeoff, but the takeoff, course control, and landing were performed by autopilot with no human engagement. See also this report from the Chicago Tribune at the time.