Sonex Aircraft Sonex

Single Piston

The Sonex is a compact, all-metal sport aircraft designed by John Monnett and introduced by Sonex Aircraft in the early 2000s as an affordable kit for amateur builders. With its distinctive Y-tail, folding wings, and aerobatic capability, the Sonex carved out a niche in the experimental light-sport category, offering builders a relatively quick build time—typically 700 to 1,000 hours—and economical operation with engines ranging from 80 to 120 horsepower. The design emphasizes simplicity and performance, achieving cruise speeds around 140 knots on modest fuel burns, making it popular among sport pilots and budget-conscious aviators seeking genuine stick-and-rudder flying. The Sonex family has expanded to include the stretched two-seat Waiex, the single-seat Onex, and even an electric variant, the e-Flight Sonex, which in 2013 became one of the first manned electric aircraft to complete sustained flight testing. Its low empty weight—under 600 pounds for some variants—and robust construction have made it a favorite at fly-ins and air races, where Sonex aircraft regularly compete in Sport Class events. SkyMeter has tracked 94 flights across 27 airframes and 23 operators, with WENDELBURG KEVIN R the largest observed operator.