Hermeus Quarterhorse Mk 2.1 completes first unmanned supersonic flight
Hermeus said Quarterhorse Mk 2.1 reached Mach 1.21 on its third test flight from Spaceport America over White Sands Missile Range airspace.
Evidence notes
- The flight occurred 364 days after the maiden flight of the company's first aircraft, Quarterhorse Mk 1.
- Quarterhorse Mk 2.1 is powered by a Pratt & Whitney F100 engine and is the first of three F-16-scale vehicles in the current flight-test roadmap.
- Hermeus said it was continuing the Mk 2.1 campaign while building Mk 2.2 and preparing Mk 2.3.
Company context
Hermeus develops high-speed unmanned aircraft for U.S. and allied defense missions, using rapid flight-test iterations across its Quarterhorse and Darkhorse programmes. Its April 2026 Series C package combined $200M of equity with $150M of debt and valued the company at $1B; the aircraft are remotely controlled rather than autonomous.