I have just had a day photographing Red Kites, the method I used was to point my camera to get a meter reading from the green grass in the field at about F6.3 with a shutter speed of at least 1/500sec and if the light doesn't allow this keep bumping the iso up until you get the right shutter speed. Then turn you camera to manual and put the same settings in, this way when you point your camera to the sky you wont get a silhouette . Then its A1servo plus panning and firing off as many shots as your camera will allow. Then just see if you have been lucky enough to get one with a sharp eye. Hope this helps.
This was one I took:
