This says they can be designed to be passively stable, and indeed have existed since the 1930s: https://aviation.stackexchange.com/questions/2252/how-does-a-fly

This says they can be designed to be passively stable, and indeed have existed since the 1930s: https://aviation.stackexchange.com/questions/2252/how-does-a-flying-wing-keep-from-going-into-a-flat-spin-when-maneuvering https://aviation.stackexchange.com/questions/2252/how-does-a... I think it requires a little more careful design then traditional plane bodies, so there is some sense in which flying wings are less stable naturally. But the claim that flying wings are necessarily unstable without computer control seems to be false.