Hermeus Quarterhorse becomes first private unmanned supersonic jet

Hermeus said its Quarterhorse Mk 2.1 test aircraft hit Mach 1.21 (~930 mph) on its third flight from Spaceport America over the White Sands Missile Range, making it the first privately-developed unmanned aircraft to break the sound barrier and, by Hermeus's claim, the fastest unmanned jet flying today. The milestone came 364 days after Hermeus's Mk 1 maiden flight and roughly three months after Mk 2.1's first flight, validating the iterative build cadence behind the company's path to its Mach 5 Darkhorse military UAS.