I just point and shoot on auto!
plane http://i279.photobucket.com/albums/kk134/redgrittybrick/DSC_6308.jpg (Gloster Gladiator I, Nikon D50, 180-200 VR)
I try to find a good place to stand, watch how the planes use the airspace, consider what sort of angles I want to shoot. Hope for good weather. Pan with the plane.