For a great WWI movie about the war in the air, I recommend The Red Baron "der rote Baron" (2008) starring Matthias Schweighofer as a perfect Rittmeister Manfred Freiherr von Richthofen.
The movie was criticized for some historical inaccuracies, but overall I think it is a very good movie with interesting characterizations, a plot and great aerial combat scenes. His red Albatros of Jasta 11 is nicely portrayed.
