Hermeus, the Atlanta-based startup racing to build a Mach 5-plus unmanned aircraft for the U.S. military, has closed a $350 million Series C funding round that pushes its valuation to $1 billion. The milestone, announced by the company in June 2025, makes Hermeus one of the few venture-backed defense startups to reach unicorn status before delivering a production vehicle. It also places a very large bet on a simple premise: that an aircraft fast enough to outrun every surface-to-air and air-to-air missile in current inventories would fundamentally change how the Pentagon projects power. Hermeus was founded in 2018 by CEO AJ Piplica and a small team of engineers with backgrounds at SpaceX and Generation Orbit, a launch-vehicle company. The founding thesis was that reusable hypersonic flight had been stuck in government-lab limbo for decades and that a startup culture could move faster. Within two years, the company had test-fired a turbine-based combined-cycle engine called Chimera, which is designed to accelerate from a standstill through the transonic range on jet power and then transition to ramjet mode for sustained hypersonic cruise. That engine architecture is the technical core of the company’s vehicle programs. Quarterhorse, a smaller autonomous demonstrator, is intended to validate the full flight envelope up to Mach 5 and beyond. Darkhorse, a larger platform, is the operational concept aimed at military missions. Hermeus has disclosed contracts with both DARPA and the U.S. Air Force, including work associated with the Mayhem program, a Pentagon effort to develop a large, reusable hypersonic aircraft capable of carrying payloads over long distances at extreme speed.

Full report : Hermeus, the Atlanta-based startup racing to build a Mach 5-plus unmanned aircraft for the U.S. military.

For more see the OODA Company Profile on Hermeus.