Hermeus raises $350M to build the fastest unmanned aircraft in the world

Hermeus, the Atlanta-based defense aviation company developing high-Mach unmanned aircraft, has closed a $350 million Series C round that values the company at $1 billion. The round, announced today, was led by Khosla Ventures and brings Hermeus’ total capital raised past $500 million. The funding arrives weeks after the company’s Quarterhorse Mk 2.1 completed its maiden flight at Spaceport America in New Mexico in late February, an F-16-sized unmanned aircraft now working toward supersonic speeds over White Sands Missile Range.

The $350 million comprises $200 million in equity and $150 million in debt. Existing backers Canaan Partners, Founders Fund, RTX Ventures, Bling Capital, and In-Q-Tel (the CIA’s venture arm) all participated again. New investors include Cox Enterprises and its venture fund Socium Ventures, Destiny Tech100, Georgia Tech Foundation, 137 Ventures, and GSBackers. Debt financing comes from Silicon Valley Bank, Pinegrove Venture Partners, Hercules Capital, and Trinity Capital.

Three aircraft, one goal: Mach 3 and beyond

Hermeus is scaling production toward a fleet of three distinct aircraft, each designed to push incrementally deeper into the supersonic and hypersonic flight envelope. The Quarterhorse Mk 2.1, which flew its first sortie in late February 2026 at Spaceport America, is powered by a Pratt & Whitney F100 engine fitted with Hermeus’ proprietary precooler. It received its FAA Special Airworthiness Certificate on March 12. The next variant, the Mk 2.2, is expected to become the world’s fastest unmanned aircraft. After that, the Mk 3 will carry Hermeus’ Chimera turbine-based combined-cycle (TBCC) engine, which transitions from turbine power at low speeds to a ramjet at high Mach.

The long-term target: surpass the Lockheed SR-71 Blackbird’s air-breathing speed record of Mach 3.32, set in 1976, and eventually reach Mach 5. That would put the company in hypersonic territory, a capability the Department of Defense has funded through contracts including the Defense Innovation Unit’s HyCAT initiative and a $60 million Air Force deal signed in 2021.

“Speed is life for us,” said AJ Piplica, founder and CEO of Hermeus. “This new funding lets us build multiple aircraft at the same time and scale our manufacturing capabilities.” The capital, he said, accelerates Hermeus’ path to ramjet-powered flight.

Hermeus splits operations between El Segundo and Atlanta

To absorb the new capital, Hermeus is opening a new headquarters in El Segundo, California, dedicated to expanded prototyping. The existing Atlanta facility will shift its focus to production. This dual-site model mirrors what other defense tech startups have adopted as they move from prototype to operational delivery. Shield AI, for instance, built its X-BAT autonomous fighter jet from concept to flying test article in 18 months by running parallel development and manufacturing operations.

One detail worth noting: Hermeus uses “Department of War” in its official communications instead of Department of Defense, a deliberate throwback that signals how the company sees its mission. The end goal beyond Quarterhorse is Darkhorse, a reusable hypersonic UAS designed for ISR and penetration of contested airspace at speeds that make interception extremely difficult.

Defense tech funding shows no signs of cooling

Hermeus’ $1 billion valuation lands in a crowded field of venture-backed defense companies chasing Pentagon dollars. Anduril is currently raising $4 billion at a reported $60 billion valuation. Chaos Industries raised $510 million in November 2025 at a $4.5 billion valuation for its counter-drone radar systems. Neros Technologies, founded by two former teenage drone racers, has raised $121 million and won Army and Marine Corps FPV drone contracts.

What sets Hermeus apart is the speed regime. Most current U.S. Air Force unmanned programs, including the General Atomics YFQ-42, the Anduril YFQ-44 Fury, and the Kratos XQ-58 Valkyrie, are subsonic. Hermeus is the only venture-backed company actively flight-testing an unmanned aircraft built to go supersonic and eventually hypersonic. That fills a gap the Pentagon has identified but not yet addressed through a formal program of record.

Meanwhile, China is developing its own hypersonic drone carrier, an unmanned mothership designed to deploy drone swarms at Mach 5. The race for high-Mach unmanned capability is not a theoretical exercise.

DroneXL’s Take

I’ve tracked defense tech funding for years, and the pattern is clear: the money is moving from small autonomous systems into bigger, faster platforms. When I covered the Chaos Industries $510 million raise last November, I asked whether massive valuations built on limited Pentagon contracts would hold up. That question applies here too, though Hermeus has something most defense startups don’t: a flying aircraft that’s already cleared FAA experimental certification and is actively expanding its flight envelope over a military test range.

The In-Q-Tel participation tells you who’s paying attention. The CIA’s venture arm doesn’t invest casually. RTX Ventures returning is just as telling, given that Pratt & Whitney (an RTX business) supplies the F100 engine powering the Quarterhorse. That’s not passive investing. That’s a propulsion supplier backing its own hardware integration pathway to hypersonic flight.

Expect the Quarterhorse Mk 2.2 to attempt a supersonic flight before the end of 2026. If it succeeds, Hermeus will hold the speed record for an unmanned aircraft, and the conversation around a Darkhorse program of record will get very real, very fast. The Pentagon needs a reusable high-Mach ISR platform. Hermeus is the only company flight-testing one right now.

DroneXL uses automated tools to support research and source retrieval. All reporting and editorial perspectives are by Haye Kesteloo.