You should read up on the SEVIS website as to what a F1 visa is all about.
Coming to the US for training is totally different than coming for employment - which it seems is what you are after.
The F1 is aimed at the zero hour student and at the end of the full course of study, the individual may be able to get OPT but it isn't guaranteed (regardless of what the Flight School might advertise). OPT is also time limited so any mention as to how many hours can be accomplished - take with a large pinch of salt as there will be plenty of others in the same position.
If a Flight school wishes to employ a fully qualified person from overseas they can sponsor that person for a full employment visa -e.g. an H1. but they cannot bring them in on an F1 or an M1 and they certainly cannot employ them without a work visa.