In Warhammer, flight is represented by a 'long swoop' or 'glide' of up to 20". The flyer starts off on the ground, takes off, flies to where it wishes to go, and then lands. Flyers, therefore, begin and end their movement on the ground. Flyers never need to wheel or turn, but can always make their move in a direct line. Of course, they still need to see any target they want to charge or shoot at and have a 90° arc of sight to their front, as normal.
Flyers do not benefit from the extra Move distance conferred on ground moving models for charging or marching. The flying move is never doubled and flyers charge at normal speed as explained.