Hermeus, an aviation startup focused on supersonic and hypersonic aircraft, is accelerating rapid innovation by embracing risk and iterative learning. In three years, the company has built three vehicles and flown two new jets just nine months apart.

With a $350 million Series C financing led by Khosla Ventures, Hermeus will expand its fleet and advance its Quarterhorse program, including the Mk 2.2 supersonic and Mk 2.3 Mach 3 aircraft.

The funding supports new facilities in El Segundo and Atlanta to scale prototyping and production, aiming to deliver high-speed aircraft for the U.S. military while prioritizing rapid development and operational advantage.