Hermeus, an aerospace innovator based in Atlanta, has successfully conducted the first flight of its Pratt & Whitney F100-229-powered Quarterhorse Mk. 2.1 supersonic demonstrator at Spaceport America, New Mexico.
This achievement signifies a significant milestone in Hermeus’s rapid development cycle, beginning with a smaller Mk.1 model flown earlier in 2025. The Mk. 2.1 is being designed as a high-speed unmanned aircraft for national defense, capable of reaching Mach 1.25, and comparable in size to an F-16 fighter jet.
Development and Future Goals
The current aircraft’s design omits several advanced features planned for future versions, such as the variable-geometry spike inlet and a full pre-cooler system, components critical for sustained high Mach flight. Piplica, Hermeus’s founder and CEO, detailed that the Mk. 2.1 was primarily built to validate basic supersonic capabilities, with subsequent models aimed at demonstrating mode shifts and integrating the complete turbo-ramjet propulsion system.
“The goal is to demonstrate the aircraft's ability to go supersonic without the full set of subsystems,”
said A.J. Piplica, highlighting the phased testing approach.
Following a successful takeoff from the 12,000-foot runway at Spaceport America, the Mk. 2.1 returned safely after its first flight, paving the way for upcoming tests involving approach maneuvers, subsonic flights, and high-altitude supersonic demonstrations. Future versions are expected to incorporate additional propulsion system elements to support speeds between Mach 2.5 and Mach 3, including the full TBCC system.
The ongoing development indicates Hermeus’s push to establish an operational high-Mach unmanned aircraft platform, leveraging innovative propulsion technology for national defense applications.
