Aerobatics is the practice of flying maneuvers involving aircraft attitudes that are not used in conventional passenger-carrying flights. The term is a portmanteau of "aeroplane" and "acrobatics". Aerobatics are performed in aeroplanes and gliders for training, recreation, entertainment, and sport. Additionally, some helicopters, such as the MBB Bo 105, are capable of limited aerobatic manoeuvres. An example of a fully aerobatic helicopter, capable of performing loops and rolls, is the Westland Lynx.
Most aerobatic manoeuvres involve rotation of the aircraft about its longitudinal axis or lateral axis. Other maneuvers, such as a spin, displace the aircraft about its vertical axis. Manoeuvres are often combined to form a complete aerobatic sequence for entertainment or competition. From Wikipedia
