I happen to live next to a small airport. Every year they have an air show, the following pics where shot with a Nikon D-70s with a 70-300 lens. The trick I learned with these shoots is shooting speed helps out a lot. Frames per second actually mean something when your trying to get close shots on jets.
First off is my favorite of the shoots, an F-14 on an angle with I think afterburner on.
The next two where average quality shots of an F-16. But the 2nd shot catches him when he has inverted the plane.
The last shot is a little out of focus but it's one of my favorite planes, an F-4U Corsair. After the breakneck shooting of jets, a prop plane was actually harder for me to readjust to. Plus I think this almost makes it look like a toy instead of a real plane.