An ultralight trike is a type of powered hang glider where flight control is by weight-shift. These aircraft have a fabric flex-wing from which is suspended a tricycle fuselage pod driven by a pusher propeller. The pod accommodates either a solo pilot, or a pilot and a single passenger. Trikes grant affordable, accessible and exciting flying, and have been popular since the 1980s.
Trikes are referred to as "microlights" in Europe. Such aircraft are also known as 2-axis microlights, flex-wing trikes, weight-shift-control aircraft,microlight trikes, deltatrikes or motorized deltaplanes,
The history of the trike is traced back to the invention by Francis Rogallo's flexible wing and subsequent development by the Paresev engineering team's innovations and then others. On 1948, engineer Francis Rogallo invented a self-inflating wing which he patented on March 20, 1951, as the Flexible wing. It was on October 4, 1957, when the Russian satellite Sputnik shocked the United States and the space race caught the imagination of its government, causing major increases in U.S. government spending on scientific research, education and on the immediate creation of NASA. Rogallo was in position to seize the opportunity and released his patent to the government and with his help at the wind tunnels, NASA began a series of experiments testing Rogallo's wing – which was renamed Para Wing – in order to evaluate it as a recovery system for the Gemini space capsules and recovery of used Saturn rocket stages. F. Rogallo's team adapted and extended the totally flexible principle into semi-rigid variants. This mainly involved stabilizing the leading edges with compressed air beams or rigid structures like aluminum tubes. By 1960 NASA had already made test flights of a powered heavily framed cargo aircraft called the Ryan XV-8 or Fleep (short for 'Flying Jeep') and by March 1962, of a weight-shift experimental glider called Paresev. By 1967 all Para Wing projects were dropped by NASA in favor of using round parachutes without officially considering development of personal ultralight gliders, but the airfoil's simplicity of design and ease of construction, along with its capability of slow flight and its gentle landing characteristics, did not go unnoticed by hang glider enthusiasts. The challenge then, was to modify and fit a Rogallo flexible wing with an appropriate frame to allow it to be used as a hang glider.