While it is still disputed to this day, as far as I know, Roy Brown got, and still has, the credit for Von Richtofen...
the infowarrior
I saw a show on The Military Channel that indicated that Richtoffen was brought down by .303 rounds from British soldiers on the ground.
Saw a show on the Military History Channel that made a pretty convincing argument he was actually killed by some of the ground troops, specifically named and positioned.
Looking at all the facts, I think the Aussie infantry firing at the plane got him.