it's that 'being in the air' bit that always gets me
Nelson Minar details why flying a plane is hard.
Planes at altitude have a lot of potential energy. A primary challenge of landing a plane is learning how to bleed that energy off to make a soft landing. In a car you just brake. And if something goes wrong in your car you can pull over to the shoulder and stop; that doesn't work so well in a plane.
Read it all the way through and tell me your brain doesn't hurt just thinking about it.