With Flight Testing Coming Along Nicely, Sonex Eyes Increased Production

Sonex says they’ll take orders for their upcoming Highwing, now that “performance and handling has proven to be exactly what we’ve expected”!

The much-anticipated kit takes everything beloved about the basic Sonex design and adds a namesake high-wing design, increasing ground clearance, visibility, and a little sun shade in place of the basic bubble canopy. The design isn’t totally out of the oven yet, as flight testing will be completed “this Fall”, but Sonex will take Kit Reservation Deposits with an eye towards shipments by the start of 2026.

All-in, the airframe will cost $39,000, while a quick-build iteration of the same will set you back $55,000. Add tricycle gear for a cool $1,250. If you’d like to eat that elephant one bite or bill at a time, then a series of sub-kits can be had to build it up in sections.

The Highwing will need an appropriate engine and avionics setup, of course, which should be factored into the price too. Sonex recommends the UL Power UL350iS in their testing so far, saying it has performed exceptionally, with no cooling problems so-far during the engine break-in phase, and offers lots of power on-tap.” The Sonex testbed is paired with a Sensenich prop for now, which is giving them about 2,700 to 2,750 RPM at WOT, but they believe they can get a little more speed out of it with a different pitch. “We have been somewhat limited in test flight altitudes by weather, and the cruise speeds observed so far at low altitudes with an under-pitched prop are exciting,” they said. Once they get a better prop setup, they will be performing reduced power tests to better estimate performance with other engines.

So far, Sonex is seeing a 53.9-mph clean stall speed, 46-mph Flaps 30º stall, 1,475-fpm climb, and 150-mph IAS in cruise. Wide-open, they’re getting about 160 mph indicated, or 170 mph true at 2,700 feet and 3,000 rpm. For a little homebuilt that’s pretty darn good, especially knowing there’s a little more performance left on the table still. Currently, the basic taildragger weighs less than 820 pounds, with the short ‘aerobatic wing tips’ and a dual-panel Dynon panel. That’s probably going to be their “Basic Empty Weight” in the future, since it’s about “the lightest that you can build the aircraft” thanks to the UL Power engine. That 350i, Sonex says, is the “lightest firewall-forward installation among our supported options of AeroVee Turbo, Jabiru 3300, UL Power, and Rotax.” (And they even clarify that surprisingly, the Rotax installs weigh more than the UL Power once they have the accessories and coolant.)

Sonex says they expect lead times of 16 to 20 weeks, and they’re already building out additional production capacity for increased output. Quick-Build kits will take a little longer, however, since they’re hand-assembled by Sonex staff. Those will get built in batches of 5 to 7 at a time while they retool and train new hands. The earliest QB deliveries should take place in Spring or early Summer 2026, while later serial numbers among the first 33 QB orders will be shipped in 2027. All of that is to say that Sonex holds more than 70 Highwing orders at the moment, so anyone who wants to get their build started in the next year or two would do well to put some money down soon.

FMI: www.sonexaircraft.com