Family-Owned Kit Manufacturer Works Dark Magic

Founded, owned, and funded by brothers Ryley, River, and Keegan Karl—a trio of University of Wisconsin graduates with respective degrees in aerospace, computer/electrical, and mechanical engineering—DarkAero is the embodiment of a shared aspiration to develop a kit aircraft of surpassing speed, range, and efficiency.

The aircraft to which the brothers Karl have plied their considerable expertise and energies is the DarkAero-1, a single-reciprocating-engine, low-wing, retractable-tricycle-undercarriage, normal category airplane, the claimed performance of which beggars belief.

With a fuselage length of 18-feet, a wingspan of just under 24-feet, and an empty weight of 750-pounds, the DarkAero-1 is not a large airplane. The machine’s 750-pound useful load impresses, as does the 5.2-liter, six-cylinder, four-stroke, two-hundred-horsepower, UL Power UL520iS engine by which it’s motivated.

It is not, however, until one contemplates the DarkAero-1’s 240-knot (TAS) cruise speed, 1,477-nautical-mile range (at 240-knots!), and FL200 service ceiling that the aircraft’s improbable potency becomes apparent. What’s more, a bit of throttle-restraint will see the DarkAero-1 cover an astounding 1,912-nautical-miles (with a thirty-minute VFR reserve, no less) at a jaunty 222-knot economy cruise speed.

The DarkAero-1’s 61-knot stall-speed is commensurate with an aircraft of its speed-optimized design, as is the contraption’s 2,500-foot-per-minute climb-rate. Of lesser orthodoxy is the Hollow Grid structure of the DarkAero-1’s wings. “Hollow Grid” denotes an arrangement of CNC cut, carbon fiber and honeycomb sandwich panel ribs and shear webs. By design, the entirety of in-flight compressive, tensional, and torsional loading acting on the DarkAero-1 is borne by the wing’s outer skin, while the Hollow Grid keeps the skin’s shape and prevents buckling. Wings comprising Hollow Grid architecture are stronger and lighter than those deriving of conventional aluminum, rib and spar designs.

Home-building the DarkAero-1 requires neither complex jigs nor fixtures—only simple shop tools. The aircraft’s carbon fiber composite airframe is fashioned in-factory by dint of computer designed, precision CNC machined tooling. The process produces smooth, accurate parts that fit together with minimal sanding.

The DarkAero-1 kit includes: airframe, canopy, engine mount, landing gear, control hardware, and fittings and fasteners. Separately purchased components include: UL Power 520iS engine, avionics, propeller, wheels and brakes, and paint. The aircraft’s estimated completed cost is $200,000.

A number of milestones by which the DarkAero-1 advanced ever nearer its inaugural flight were achieved in 2022. These included integration of the prototype’s fuel system, landing gear, and avionics; installation of the acrylic canopy; integration of the canopy release mechanism; and development of a latch system to keep the canopy secured in flight. Functional testing saw the aircraft’s first engine start and taxi evaluations, as well as ground vibration assessments.

Among the more exciting events to play out at DarkAero in 2022 occurred near year’s end, when the brothers Karl met with test pilot Sean VanHatten of Initial Approach Aerospace. Discussions were had regarding the DarkAero-1’s design, and a plan for flight testing the prototype in 2023 was laid out.

As the DarkAero-1 proceeded steadily upon its evolutionary course, the company’s trio of founders identified and secured a space in which to undertake the initial phase of kit production. Subject space was built to DarkAero’s (company) requirements, and has since been populated with production tools, molds, CNC equipment, and a cure oven.

Mounting demand for DarkAero-1 kits has sent reservations for such soaring from 133 to 177 units. The boon, though welcome, exceeded the Karl brothers’ expectations, and has compelled them to wax conservative about the timeline on which DarkAero-1 customers ought expect delivery of their kits. As engineers and sole proprietors of an aerospace concern, the Karls’ first priority is implementing a manufacturing scheme conducive to turning out a top-quality product. Only after that objective is met do the brothers intend to turn their efforts to accelerating kit production.

FMI: www.darkaero.com