Quarterhorse Hypersonic Test Aircraft Completes First Flight

June 4, 2025

Hermeus's Quarterhorse MK1 sitting on the lakebed at Edwards Air Force Base. (Image: Hermeus)

Hermeus, an Atlanta, Georgia-based startup, completed the first flight of its Quarterhorse MK1 test aircraft. The first flight is the latest milestone achieved by Hermeus in its goal of developing high-Mach and hypersonic aircraft.

Quarterhorse Mk1 is the first flight test aircraft in a series of test aircraft that Hermeus is developing. Their test aircraft development roadmap's ultimate goal is to break the all-time airspeed record held by the SR-71 with the Quarterhorse MK3. The MK1 is a remotely piloted aircraft powered by a GE J85 engine, and Hermeus is using it to demonstrate high-speed takeoffs and landings, which they achieved with the first flight test at Edwards Air Force Base, California last week.

“Mk 1 has redefined the pace of developing and flying new aircraft,” said Hermeus CEO and Co-Founder, AJ Piplica. “I’m incredibly proud of what our team has accomplished. We’ve proven the viability of our iterative development approach. But this is just the start. We have much more to do as the bar rises for the next iteration.”

Quarterhorse Mk 1 went from clean sheet to flight-ready in a little over a year. The primary focus of the test campaign was to validate high-speed takeoff and landing of a large uncrewed aircraft. The aircraft's unique configuration — driven by high-speed flight — makes basic operations of takeoff and landing distinctly challenging. The company has also been engaged with the Department of Defense (DoD) on its development roadmap, including participating in the Defense Innovation Unit's (DIU) Hypersonic and High-Cadence Airborne Testing Capabilities (HyCAT) initiative .

“Industry partnerships continue to have an important role in the development and test of disruptive and innovative capabilities for our warfighters,” commented Major General Scott Cain, Commander of Air Force Test Center. “The promise of routine hypersonic flight is an exciting capability for the joint team.”

Data from the campaign has validated design and performance models, including aerodynamics, stability and control. Testing also validated performance of vehicle subsystems including propulsion, fuel systems, hydraulics, power, thermal management, avionics, flight software, telemetry, flight termination, and command and control.

“The real-world flight data from Mk 1 provides significant technical value that we’re rolling into our next aircraft,” said Co-Founder and President Skyler Shuford. “Moreover, the team has accomplished this milestone on a challenging timeline while operating within the overall aerospace ecosystem — all to support rebuilding America’s lost capability to quickly develop brand-new, full-scale jets.”

The Hermeus development roadmap emphasizes "hardware richness," building multiple prototypes in quick succession, allowing the team to take well-managed technical risk. While driving technical progress towards high-speed flight, this approach simultaneously enables Hermeus to rapidly develop its team and talent. The “one aircraft per year” development cadence drives Hermeus’ engineers and technicians through multiple crucibles of full life-cycle aircraft development in a very short time period. As a result, the company is progressively building a team capable of solving the hardest engineering challenges of aviation to operationalize hypersonic aircraft.

The team is actively reviewing data and integrating lessons learned into Hermeus’ next iteration, Quarterhorse Mk 2, currently being manufactured at Hermeus’ headquarters in Atlanta. The scale of an F-16, Quarterhorse Mk 2 is a high-Mach aircraft designed to de-risk uncrewed supersonic flight. It is on-track to fly late this year. This vehicle will enable both high-cadence hypersonic flight test and novel operational defense capabilities.

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