GTC58 said
The B777 has a super critical wing, as such it is not really designed to have aerodynamic inherent stability. Without pilot inputs it doesn't take very long for the aircraft to depart its altitude and flight path in manual flight.
This is not true at all. The B777 is a fly by wire aircraft, the aircraft is flow by the primary flight computers (PFC) which interpret pilot inputs to the flying controls and the current flying conditions (speed, alt, configuration) and move the control surfaces as appropriate. If there is any inherent instability of the wing design it is irrelevant.
If the the auto pilot is switched off and the pilot makes no input on the flying controls the aircraft will continue to fly on roughly the same path as it was before the A/P disconnected.