Additively manufactured engines: Beehive tests 3D-printed Frenzy propulsion system at high altitude

The growing use of additive manufacturing is noticeably changing development cycles in the aerospace sector. A recent example comes from Beehive Industries, a U.S.-based manufacturer of propulsion systems for unmanned aircraft. The company has recently completed a high-altitude test campaign for its Frenzy engine, producing around 200 pounds-force of thrust, thereby meeting a key prerequisite for upcoming flight tests.

The tests were conducted at a government test facility in the U.S. state of Ohio and covered the engine’s entire intended operating envelope. Among other aspects, ignition behavior, acceleration characteristics, and thermal stability under reduced ambient pressure were evaluated.

“The milestone confirms Frenzy’s readiness for flight integration,” said David Kimball, Chief Technology Officer at Beehive Industries. “In less than a year, we’ve gone from concept to proven high-altitude performance — and we’re doing it ahead of schedule because of the talented and determined team at Beehive. Frenzy is now flight-ready, and our production system is ready to scale alongside it.”

Beehive follows a so-called additive-first approach, in which core engine components are designed for 3D printing from the outset. This enables the realization of complex internal geometries—such as cooling channels or flow-optimized combustion chambers—without the need for subsequent assembly. At the same time, iteration times between design changes and test runs are significantly shortened, as tooling and casting molds are eliminated. According to the company, the tested engines showed no significant signs of wear after a mission-equivalent operating duration.

“This test campaign not only demonstrates the full potential of our engine, but also how we move with speed through a highly iterative, cross-functional development program,” Kimball added. “Each milestone strengthens our confidence in the architecture, our ability to deliver on our commitments, and the disruptive path we’re charting for next-generation propulsion. We’re not just accelerating development timelines — we’re ensuring America’s warfighters have the technology they need, when they need it most.”

The Frenzy engine family is designed for thrust classes between 100 and 300 lbf and is intended to power a range of unmanned platforms in the future. With planned flight tests in early 2026 in view, Beehive is already preparing to ramp up additive serial production at multiple sites. The program is supported, among others, by funding from the U.S. Air Force, which views additive manufacturing as a lever for accelerating defense-relevant development projects.