Hermeus Secures $350 Million to Accelerate Unmanned Hypersonic Fighter Production

Defense startup Hermeus raises $350 million to develop unmanned Mach 5 aircraft using modified Pratt & Whitney engines for U.S. government contracts.

By: AXL Media

Published: Apr 8, 2026, 5:34 AM EDT

Source: Information for this report was sourced from TechCrunch

Strategic Capital Influx for Hypersonic Aviation

Hermeus, a Los Angeles based defense firm, has announced a $350 million funding milestone aimed at advancing its goal of building the world’s fastest unmanned aircraft. The round includes $200 million in equity financing led by Khosla Ventures, alongside contributions from RTX Ventures, Canaan Partners, and Founders Fund. According to CEO AJ Piplica, the addition of $150 million in debt allows the company to expand its manufacturing infrastructure while maintaining greater control over its cap table, a move designed to facilitate the capital intensive nature of hardware production.

Pivoting to Proven Engine Technology

A critical shift in the company’s technical strategy involved moving away from internal engine development to a partnership with Pratt & Whitney, a subsidiary of RTX. By modifying the existing F100 engine for hypersonic use, Hermeus has significantly shortened its development timeline. President Zach Shore stated that this decision accelerates the path to Mach 5 flight while simultaneously meeting immediate demand from the Department of Defense. This approach allows the company to iterate more quickly using functional, flight proven hardware rather than waiting for entirely new engine designs.

Rapid Prototyping and Industry Standards

The company is adopting a development philosophy similar to SpaceX, prioritizing a cycle of building, testing, failing, and learning. Hermeus recently flew a demonstrator aircraft the size of an F-16 and is currently working on a third iteration intended for supersonic speeds. Piplica noted that the industry rarely sees new full-scale aircraft built on an annual basis, and the new funding will help cultivate the specialized talent necessary to maintain this aggressive prototyping schedule. The company’s workforce is currently approaching 300 employees as it scales operations.