Atlanta’s hypersonic plane startup Hermeus raises $100 million

The company has an 110,000 square-foot factory in Doraville, and over the last year it has been conducting engine tests and building a prototype of its first aircraft.

Hermeus is trying to develop a hypersonic plane that can fly at Mach 5 — more than twice the speed of the supersonic Concorde — to allow passengers to fly across the Atlantic Ocean in 90 minutes. It’s expected to take years to develop and get certified even if the project is successful.

Last year it announced a $60 million contract from the U.S. Air Force and a research and development agreement with NASA, and said this week it plans to “bring hundreds of millions of private dollars to develop this technology.”

The latest funding is led by Sam Altman, former president of startup accelerator Y Combinator and CEO of artificial intelligence research and development firm OpenAI. Other new investors in the funding round include Founders Fund and In-Q-Tel, which joined existing investors Khosla Ventures, Canaan Partners, Bling Capital and Revolution’s Rise of the Rest.

Hermeus said it will use the so-called Series B funding to finish development of its first aircraft, called Quarterhorse, an autonomous high-speed plane it plans to test fly next year to validate its engine technology. It also plans to use the funding to develop a hypersonic-capable, crewless aircraft it calls Darkhorse.

It plans eventually to develop a commercial passenger aircraft it calls Halcyon.

“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,” Altman said in a written statement.