Aviation
In aviation, the maneuver includes a constant variation of aircraft attitude (nose orientation) in all three axes, and at the midpoint (top) of the roll, the aircraft is flying inverted, with the nose pointing at roughly a right angle to the general path of flight. The term "barrel roll" is frequently used, incorrectly, to refer to any roll by an airplane (see aileron roll). Most often, a barrel roll refers to a helical roll around the relative forward motion of the aircraft, in which the nose ends up pointed along the flight path. It is performed by doing a combination of a roll and a loop.
Outside of aerobatic competition, the Boeing 367-80 and Concorde prototype were barrel rolled during testing. The Boeing 367-80 was rolled twice by Tex Johnston in an unauthorized maneuver while demonstrating the aircraft to the International Air Transport Association over Lake Washington, Seattle. Concorde was rolled multiple times by her test pilots, including Jean Franchi and Brian Walpole. Avro test pilot Roly Falk rolled the Avro Vulcan during a display at the 1955 Farnborough airshow, gaining height during the manoeuvre.
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