• Hermeus reported Quarterhorse Mk 2.1 completed its first supersonic flight, reaching Mach 1.21 on its third test flight.
• The unmanned jet flew supersonic less than three months after its first flight, 364 days after the company’s Mk 1 maiden flight.
• Quarterhorse Mk 2.1 is powered by a Pratt & Whitney F100 turbofan engine, part of a rapid-iteration development roadmap.
• Work is underway on Quarterhorse Mk 2.2, with Mk 2.3 planned to push toward sustained high-Mach flight.

Disclaimer: This news brief was created by Public Technologies (PUBT) using generative artificial intelligence. While PUBT strives to provide accurate and timely information, this AI-generated content is for informational purposes only and should not be interpreted as financial, investment, or legal advice. Hermeus Corp. published the original content used to generate this news brief on May 26, 2026, and is solely responsible for the information contained therein.