China just approved flying taxis – no pilot needed

I definitely don't want to belittle the achievement, but I would imagine that creating safe self-driving helicopters is much easier than creating safe self-driving cars. (At least as long as the skies are just as empty as they are today. Once it's full of things like the roads, that will be a different topic)

1 word: birds.

Anyway, detecting and avoiding obstacles should be in the menu. Maybe not as complex as at street level with people and cars doing unexpected things, but maybe with some added complexity that need to have into account like weather, inertia and things near landing sites.