In aviation, a class rating is an allowance to fly a certain group of aircraft that require training common to all aircraft within the group. A type rating is specified if a particular aircraft requires additional specialized training beyond the scope of initial license and aircraft class training. Which aircraft require a type rating is decided by the local aviation authority. Almost all single-engine piston (SEP) or multi-engine piston (MEP) single pilot aircraft can be flown without a type rating, but are covered by a class rating instead.