Worst ever aviation film:
Fate is the Hunter.
Why? Because it had almost nothing in common with the eponymous book, my all time favourite Aviation Book (part military, anyway!).
Best ever military aviation film:
The Memphis Belle: A Story of a Flying Fortress; Producer William Wyler (1944)
Why? Because it is a fitting tribute to all those who fought, and the many that died, in the daytime Bombing Campaign of WW2. Watch it (for free!) here:
Internet Archive: Free Download: The Memphis Belle: A Story of a Flying Fortress