Sonerai Comes Back In-House at Sonex

Back in 1971, Sonex Aircraft founder and president John Monnett began designing and building the first Sonerai 1 for $1,200—including a new engine—to compete in the newly-conceived Formula Vee air racing class. It wasn’t long before other builders began requesting plans for the aircraft, and John was in business, eventually offering the Sonerai in several configurations. Now, Sonex has grown substantially to include several popular models of plans-built and kit-built experimental aircraft.

Monnett and Sonex Aircraft announced recently that after being offered through a series of other companies, the Sonerai has come back home to Oshkosh, Wisconsin, where Sonex Aircraft is based. Plans and parts are now available for Sonerai I, Sonerai II, and Sonerai IIS aircraft directly through Sonex.

Plans were originally sold by Monnett Experimental Aircraft from 1972 through 1984 before the company was sold to INAV in 1985. John Monnett retained the Intellectual Property (IP) rights to the Sonerai series, with that license eventually given to Great Planes Aircraft, who continued to sell plans up until the principal died. Long-time Sonerai newsletter editor Fred Keip kept the Sonerai alive until his retirement last year, which prompted Sonex to again bring the Sonerai IP and parts business back in-house and integrate it into the Sonex Aircraft domain.

“Over the years, thousands of Sonerai plan sets have been sold, averaging over 100 sets annually,” Monnett said. “Although the actual number of Sonerais flying is unknown, it remains a popular homebuilt airplane that was designed to get the most performance out of the available horsepower. It is neutrally stable, aerobatic, and fun to fly. The Sonerai II mimics the first variant, and is a “utility” two-place that is fun to fly solo.”

While the first Sonerai only cost Monnett $1,200, the plans-built design today will still end up being an exceptional value to get in the air for those who have the building skills to complete the project. The Sonex website says the approximate finished cost of a Sonerai is about $21,340 including engine and basic instrumentation, and $22,940 when the 80 hp Aerovee engine is installed. “The Sonerai is a simple build,” Monnett explained, “but it is a true composite aircraft, so skills in welding, riveting, metalwork, fiberglass, fabric covering and even some woodwork are required to complete the aircraft from our plans. It is quite inexpensive to build by today’s standards, and my goal has always been to provide opportunities to build and fly an aircraft for the price of an average car.”

An interesting note is how the Sonerai line of aircraft got its name. “The name ‘Sonerai’ was derived from some mumbling, as we tried out names like Sunray, Sonic Ray, etc.,” Monnett said. “One day, Sonerai just fell out and it sounded right.” With the Sonerai now back in-house at Sonex, the many resources of that company will bring more support to new and current Sonerai builders with updated plan sets, parts, and new components that will contribute to builder success.

For those who would like to know more about John Monnett, or how his first Sonerai race plane evolved into the Sonex Aircraft company we see today, the book, “John Monnett: Sonerai to Sonex,” is sold through the Sonex webstore and details the design and history of Monnett and the company he and his family and teams have built.