The Onex, Sonex, Waiex and Xenos are a family of lightweight, metal, low-wing, two seat homebuilt aircraft.

[1][3][4] Company founder John Monnett was approached by an Italian business looking for an aircraft that would meet their Microlight category.

Eventually a clean-sheet design was built around a Jabiru or VW engine installation with similar all-aluminum box fuselage construction as the Monnett Moni.

[8] The Sonex plans contain several construction options, including conventional or tricycle landing gear, as well as a center or dual stick.

The Sonex can be built from scratch using factory supplied drawings or may be assembled in approximately 800 to 1,000 hours using the precut complete airframe kit.