I paired up my 15MM f/2.8 EF Fisheye with my Canon 5D at the Udvar-Hazy A&S Annex at Dulles Airport yesterday to see if I could capture an entire aircraft in one shot.
I found that if I keep the subject in the middle of the frame and crop at a 10x4 or 10x6 ratio I can get decent results. Here are two samples: The B-29 "Enola Gay" and an Air France Concorde...note the Connie Tri-Tail as a bonus behind the Concorde 

