The European Aviation Safety Agency (EASA) issues 200 recommendations annually. These recommendations are, quite simply, proposals to airlines, unlike directives which are of an obligatory nature. Recommendations and directives, however, do not apply to the same domains.
Dominique Fouda, Head of Communications Dpt. - European Aviation Safety Agency : watch the interview in the video.
Recommendations such as the "Rule of Two", or for no-fly zones, and the like, have the advantage of being implemented quickly. They concern only flight operations and therefore aimed exclusively at airlines. They are not mandatory unless the civil aviation authority, to which the company is attached, requires it.
Airworthiness directives (or instructions), concerning the mechanical aspects of aircraft (repairs, inspections, replacement of parts), are for aircraft manufacturers or maintenance workshops. They are often more numerous at the beginning of the life-cycle of a programme (‘‘teething problems’’ to resolve), and its end (wear and tear related problems). The European Agency issues between 400 and 500 directives per year.