FAA clears Hermeus for supersonic tests
The FAA authorised Hermeus to conduct up to seven supersonic flights of its experimental Quarterhorse Mk 2.1, marking a regulatory step toward flight testing above Mach 1. The clearance shifts the vehicle toward operational envelope expansion, instrumentation and integrated flight testing as it moves from concept and fundraising into active test flights. (airdatanews.com)
Hermeus can now take its Quarterhorse Mk 2.1 past the speed of sound under a Federal Aviation Administration authorization that took effect on April 9. (federalregister.gov) The approval covers up to seven developmental test flights through December 31, 2026, in restricted airspace over New Mexico. The Federal Register notice says the unmanned aircraft would fly at or above 30,000 feet mean sea level in R-5111 A and B and R-5107 B. (govinfo.gov) Flying faster than Mach 1 means outrunning the pressure waves an aircraft pushes through the air, which is what creates a sonic boom. In the United States, civil aircraft are generally barred from supersonic flight over land unless the Federal Aviation Administration grants a special flight authorization under federal regulations. (faa.gov) Quarterhorse Mk 2.1 is the latest step in Hermeus’ plan to build progressively faster aircraft before attempting hypersonic flight, which usually means at least five times the speed of sound. Hermeus says Mk 2.1 is its largest and fastest vehicle yet and flew for the first time on March 12, 2026. (hermeus.com) Before this clearance, the company had already secured a Special Airworthiness Certificate in the experimental category for the aircraft after what Hermeus described as a year of work with the Federal Aviation Administration. That certificate let the flight-test campaign begin while the company worked toward supersonic operations. (hermeus.com) Hermeus moved the aircraft to Spaceport America in New Mexico earlier this year and said the site would handle ground runs, taxi tests and first-flight preparation. FlightGlobal reported on March 19 that Federal Aviation Administration inspectors examined Quarterhorse Mk 2.1 at the spaceport before the experimental certification was issued. (hermeus.com) (flightglobal.com) The company’s earlier Quarterhorse Mk 1 was a smaller, remotely piloted aircraft powered by a General Electric J85 engine and flew at Edwards Air Force Base in May 2025. Hermeus says that aircraft was built to prove high-speed takeoff and landing, which it describes as a key requirement for its later high-Mach designs. (hermeus.com) Hermeus says its broader goal is to field high-Mach and hypersonic aircraft for defense use, not just a one-off demonstrator. The new authorization moves Quarterhorse Mk 2.1 from conventional test sorties into a tightly limited set of flights where the company can start collecting data above Mach 1. (hermeus.com)
