Hermeus Corporation is a pioneering American aerospace startup focused on the rapid development of high-speed, hypersonic aircraft with groundbreaking capabilities. Founded in 2018, the company aims to revolutionize air travel and defense by building aircraft that can fly at speeds up to Mach 5, drastically reducing flight times across the globe. With strong backing from venture capital and U.S. defense agencies, Hermeus stands at the forefront of hypersonic technology. This article unveils ten intriguing facets of Hermeus Corporation, from its innovative propulsion systems and rapid aircraft development cycle to its collaboration with the U.S. Department of Defense and plans for future facilities.
Hermeus was established in 2018 by a team including AJ Piplica, Zach Shore, and others with a shared vision to design and build the world’s fastest aircraft. The company’s core mission emphasizes delivering hypersonic vehicles quickly and cost-effectively, focusing primarily on national security interests. By working closely with the U.S. Department of Defense (DoD), Hermeus seeks to provide an asymmetric technological advantage through aircraft that operate at unprecedented speeds and altitudes, boosting both military and commercial aviation capabilities.
A cornerstone of Hermeus’ aircraft is its unique propulsion system—a hybrid engine that combines turbine and ramjet technologies. This engine is capable of conventional takeoff, breaking the sound barrier, and accelerating to hypersonic speeds. The design leverages a modified Pratt & Whitney F100 turbofan engine, widely used in military jets like the F-15 and F-16, adapted through collaboration with Pratt & Whitney to fit hypersonic flight profiles. This hybrid propulsion approach shortens development timelines and offers a practical, tested baseline for high-speed flight.
Hermeus is rapidly iterating on its Quarterhorse test aircraft series to refine hypersonic technologies. The Quarterhorse Mk 1 completed a successful first flight in 2025 at Edwards Air Force Base, marking a crucial milestone towards Mach 5 capabilities. The subsequent Mk 2.1 version recently obtained a Special Airworthiness Certificate (Experimental Category) from the FAA, enabling supersonic flight testing at Spaceport America in New Mexico. This swift pace—building and flying roughly one aircraft per year—illustrates Hermeus’ agile design and development philosophy.
Hermeus works directly with the U.S. Air Force and other defense entities, securing significant funding and contracts to advance hypersonic aircraft technologies. Notably, the company received a $60 million contract from the Air Force to mature hypersonic propulsion systems and flight capabilities. Partnerships with federal agencies also include the Defense Innovation Unit, aiming to leverage technology for near-term defense applications. These collaborations underscore Hermeus’ role as a key player in bolstering U.S. defense readiness through transformational aerospace innovations.
Hermeus has successfully raised over $399 million through multiple funding rounds, including a notable $350 million Series C round in 2026 that valued the company at approximately $1 billion. Leading investors include Khosla Ventures, Founders Fund, In-Q-Tel, and RTX Ventures (the venture arm of defense giant Raytheon Technologies). This enthusiastic backing from both venture capitalists and major defense corporations reflects confidence in Hermeus’ technology and strategic market positioning.
From its inception, Hermeus has expanded to employ over 275 people spread across locations in Atlanta, Los Angeles, Washington D.C., and Jacksonville, FL. The team comprises aerospace veterans from top aircraft manufacturers, defense contractors, startups, and the U.S. military. This diverse expertise enables rapid innovation and nimble execution, with a company culture that embraces iterative testing and learning to accelerate breakthroughs in hypersonic flight.
In late 2025, Hermeus inaugurated its High Enthalpy Air-Breathing Test (HEAT) Facility in Jacksonville, Florida. This cutting-edge facility is designed to test engines and propulsion subsystems for hypersonic aircraft, serving as a national asset for advanced aerospace research. HEAT supports rigorous development cycles by enabling repeated engine testing and validation crucial to pushing the aircraft’s performance envelope while making hypersonic flight more practical and affordable.
Hermeus’ hypersonic aircraft are primarily intended for defense and national security applications. The ability to rapidly deploy unmanned aerial systems operating at Mach 5 speeds offers significant tactical advantages, including rapid strike, reconnaissance, and payload delivery capabilities. Beyond military use, Hermeus envisions future commercial applications where hypersonic speeds could transform global transportation, shrinking transcontinental flight times from hours to under two.
Hermeus made major strides in regulatory approval when the Federal Aviation Administration granted its Quarterhorse Mk 2.1 Special Airworthiness Certification in the Experimental Category in early 2026. This milestone cleared regulatory hurdles for more advanced supersonic flight tests, marking Hermeus’ transition from prototypes to operationally viable platforms. The successful flights at facilities like Spaceport America demonstrate that hypersonic technologies are moving closer to routine, testable, and scalable operations.
Looking ahead, Hermeus is scaling its manufacturing and testing cadence, aiming for weekly flight test operations in support of multiple government and commercial customers. With continued capital infusion and strategic collaborations, the company plans to develop more advanced demonstrators like the upcoming Quarterhorse Mk 3, pushing toward Mach 5+ hypersonic speeds. This growth trajectory positions Hermeus as a potential disruptor in aerospace, with ambitions of not only redefining defense aviation but also revolutionizing civilian air travel worldwide.
Hermeus Corporation stands at the cutting edge of aerospace innovation, blending bold ambition with tangible progress in hypersonic flight technology. Its rapid design-build-test cycles, unique hybrid propulsion systems, and strategic government partnerships showcase a new model for fast-paced aerospace development. As Hermeus advances its hypersonic aircraft toward operational reality, it redefines what is possible in both defense strategy and global transportation efficiency. Will hypersonic flight become the new norm for air travel and national security? Hermeus is one of the key companies making that future conceivable.
