It is considerably more complicated. Apart from added axes of movement (not just vertical, but pitch/roll), you also have to contend with the fact that air is t

It is considerably more complicated. Apart from added axes of movement (not just vertical, but pitch/roll), you also have to contend with the fact that air is the only source of friction. Acceleration and breaking are much slower than something with wheels on the ground. There is a reason why flying a plane in Grand Theft Auto is much harder than driving a car, even with the simplified physics and vehicle controls. If we could make aircraft that handle in our atmosphere like the spaceship in Descent, then that would close the gap a bit. But I'm not holding my breath.