Sonex owner announces company is closing effective immediately

Sonex LLC owner Mark Schaible announced on Friday that Sonex is closing its doors effective immediately and will no longer be operational.
Sonex is a kit aircraft, engine, accessories and unmanned aircraft manufacturer based in Oshkosh, Wisconsin. The company was founded by John Monnett in 1998 and it was purchased by Schaible in 2022. Its list of aircraft includes the Sonex Onex, Highwing, JSX-2T and Waiex-B. Sonex announced on Jan. 23, 2026, the shipment of the Highwing’s Tail Kits, with the shipments of the Fuselage Kit and Quick Build Kit being originally planned for later.”We’ve had to make this decision very suddenly as a perfect storm of bank pressure, lack of sales, increasing costs, competition from our own aircraft in the used market, and cashflow realities are not allowing us to continue our work,” said Schaible in his announcement video. Schaible states that the decision to shut Sonex’s doors was made necessary due to a severe drop-off in sales and the bank’s unwillingness to carry forward the company’s debts because of unprofitable years. He asks anyone willing to step up and support the worldwide Sonex fleet to reach out and get in touch with him. The role would include completion of the work required to ship Sonex Highwing kits.
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“Many people are going to be negatively affected by this situation: Vendors, many of which we consider to be like family, our staff, and our customers,” said Schaible. “To all of you, I wish to express my most sincere apologies for this situation. I have enjoyed great relationships with so many of our customers and will sorely miss being able to talk to you and support your dreams of building and flying your own aircraft. With respect to the Sonex staff, our current team are among the finest, most talented and dedicated people I have ever had the pleasure of working with. They weigh heavily in the hearts of Char and I, and we plan to check in with them frequently. Our only consolation is knowing that with their talents and dedication, they will earn a lot more money elsewhere than they have with Sonex. If you meet any members of our staff on the street, at AirVenture, or online, I urge you all to treat them with dignity and respect, even if you’re angry.”