Startup hypersonic aircraft developer Hermeus is seeing its plans continue to take root, securing a $100 million Series B funding round that will be used to complete Quarterhorse, a remotely piloted small-size vehicle. The funding follows partnerships with the U.S. Air Force and NASA on research surrounding the development of hypersonic aircraft.

Led by entrepreneur Sam Altman, the funding brought in new investors Founder's Fund and In-Q-Tel (a strategic investor to U.S. Intelligence agencies and its allies), along with support from existing investors Khosla Ventures, Canaan Partners, Bling Capital, and Revolution’s Rise of the Rest, in the latest round.

Powered by Hermeus’s turbine-based combined cycle engines, based on the GE J85, Quarterhorse is anticipated to fly in 2023, testing speeds of between Mach 3 and Mach 5.

In addition to completing Quarterhorse, Hermeus said the funding will provide resources for flight operations and enable the company to step up work on its next aircraft, Darkhorse. The company plans to take lessons learned from the uncrewed hypersonic Darkhorse to move forward on a commercial aircraft, Halycon.

“Hermeus is pursuing an ambitious vision that seems impossible at first glance, but they pair it with an engineering culture and business roadmap that can actually bring it into reality,” said Altman. “Their experienced and passionate team will drive growth across the globe both economically and socially.”

Over the past year, Hermeus has begun to expand its operations by building out a 110,000-sq-ft factory in Atlanta, establishing a test facility, completing more than 100 engine tests, constructing a prototype of Quarterhorse, and doubling the size of its team.

“Our mission to massively accelerate global transportation requires tackling some of engineering’s hardest challenges,” said CEO AJ Piplica. “This funding starts a new phase for the company—one where the stakes are higher than they've ever been, but also where we have the resources to accomplish what some think is impossible."