Something which controls heading and speed but which does not take complete responsibility for the vehicle. And do you know what we call a device like that? We call it an autopilot. [...] Buy a fucking dictionary, and spend some time with it.
I will if you will. Let's try Merriam-Webster:
a device that steers a ship, aircraft, or spacecraft in place of a person
Or, we could look at Wiktionary:
A mechanical, electrical, or hydraulic system used to guide a vehicle without assistance from a human being.