I have always assumed that the amount of French one would need to be proficient at, in order to conduct operations in and out of a small French airfield, would be not very much. The amount of English used to converse with English A/G stations is, after all, minimal. I would have thought that if you knew your numbers, and things like "runway" "left" and "right", and a few other likely words, you'd be most of the way there.
Ou Non?