A great video of the worlds best aerobatic aircraft pilot Svetlana Kapanina flying the Su-26 aerobatic aircraft. Aerobatics (a portmanteau of aerial-acrobatics) is the practice of flying maneuvers involving aircraft attitudes that are not used in normal flight. Aerobatics are performed in airplanes and gliders for training, recreation, entertainment, and sport. Additionally, some helicopters, such as the MBB Bo 105, are capable of limited aerobatic maneuvers. An example of a fully aerobatic helicopter, capable of performing loops and rolls, is the Westland Lynx. The term is sometimes referred to as acrobatics, especially when translated. Most aerobatic maneuvers involve rotation of the aircraft about its longitudinal (roll) axis or lateral (pitch) axis. Other maneuvers, such as a spin, displace the aircraft about its vertical (yaw) axis. Maneuvers are often combined to form a complete aerobatic sequence for entertainment or competition. Aerobatic flying requires a broader set of piloting skills and exposes the aircraft to greater structural stress than for normal flight. In some countries, the pilot must wear a parachute when performing aerobatics. While many pilots fly aerobatics for recreation, some choose to fly in aerobatic competitions, a refereed sport.