I am not sure what the precise definition of a documentary film is but that is usually the section of movies I find myself browsing in iTunes. Here is my latest favorite.
“Swift. Silent. Deep. An American Rebel Story” is about the Jackson Hole Air Force and how they changed skiing and ski operations and management.
Swift Silent Deep is to snow skiing what Dogtown and Z-Boys was to Skateboarding. Both are interesting and entertaining movies about a small group of people that are fanatical about something that broke the rules and sometimes the law. Ultimately, they won, convention had to give in to both of these groups and it changed their respective sports forever.
You have to appreciate and even like the characters and their stories. They are the epitome of passion. They were committed and they prevailed.
Check it out. I think you will like it.