Competition aerobatics

Competition aerobatics is an air sport in which judges rate the skill of pilots performing aerobatic flying. It is practiced in both piston-powered single-engine airplanes and gliders.

An aerobatic competition is sanctioned by a national aero club, its designee, or in the case of international competitions, by the Fédération Aéronautique Internationale (FAI). The sanctioning body establishes the rules that apply to the competition, including entry qualifications for all participants, operating procedures and judging criteria.

A pilot enters a competition in a category of his or her choice, which defines the level of difficulty of the aerobatic sequences flown. Within each category, a pilot flies one or more flight programs. Each flight receives a total score from the judges; ranking each pilot's combined total scores for all flight programs within each category determines that category's winner.

Five power categories are flown in the U.S. (and other states that adopt the U.S. model). They vary by difficulty of the individual aerobatic maneuvers they contain, as well as the combination of those maneuvers within the sequence. In order of increasing difficulty, the power categories are:

Some aero clubs include a Classic category for airplanes without inverted fuel and oil systems. The sequences flown are similar to those flown in the Sportsman category.

Three glider categories are:

Categories flown in a competition are announced in advance.

Within each category, each pilot flies one or more flight programs. They are:

The aerobatic box is a volume of airspace in which the aircraft must remain while performing a sequence. Its length and width are each 1,000 metres (3,280 ft). Its height varies based on whether FAI, national aero club or local rules apply to the competition. White ground markers at each corner of the box make it visible to the pilot from the air. For most categories, penalties are assessed for flight outside the aerobatic box.

The box has two axes, the identification of which is based on the location of the judges. The X-Axis (called the A-Axis by some aero clubs), runs across the line of sight of the judges. It is along this axis that most figures are usually flown. In some contests a center line is marked along the middle of the X-Axis.

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