Stoke Space hotfires rocket engine on new vertical test stand — a ‘very big deal’ for Washington startup

Stoke Space successfully hotfired its first-stage rocket engine on a new vertical test stand at the company’s Moses Lake, Wash., facility on Wednesday in what was called “a very big deal” for the 4-year-old startup.

The company released dramatic photographs of the test in action, posting on X that it was an “incredible team effort.”

Kent, Wash.-based Stoke Space has been on a quest to build a new breed of fully reusable rockets and space vehicles that it says will be designed to operate with “aircraft-like frequency.”

The startup was founded in 2019 by CEO Andy Lapsa, a veteran of Jeff Bezos’ Blue Origin space venture, and Tom Feldman, who worked at Blue Origin after interning at SpaceX.

Stoke Space called the test significant for several reasons. It’s the first hotfire of the company’s Block 2 (flight layout) stage 1 engine, and this engine architecture — called full-flow staged combustion (FFSC) — is considered particularly challenging. Only two entities in the world — Stoke and SpaceX — have successfully developed FFSC engines.

“It’s a very big deal to be able to test this full-flow staged combustion engine in its flight (vertical) orientation,” Feldman, Stoke’s CTO, said in a statement to GeekWire. “This test represents the culmination of some very hard work across many different teams at Stoke, and will serve as the basis for much learning to come.”

Stoke’s stage 1 engine is a liquified natural gas/liquid oxygen engine capable of producing 100,000 pounds of thrust. The duration of the test was not revealed.

It was the first time Stoke has tested on its new vertical test stand in Moses Lake. The company’s testing philosophy is that you must “test like you fly,” and it believes vertical testing is key to engine development.

“Can’t test an engine without a test stand, and this one’s a beauty,” Lapsa said on X after Wednesday’s test. “Gorgeous clean burn using all the flows!”

Lapsa is being honored Thursday night at the GeekWire Gala in Seattle as one of this year’s five “Uncommon Thinkers,” in recognition of inventors, scientists, technologists and entrepreneurs transforming industries and driving positive change in the world.

In 2023, the Stoke raised $100 million and showcased a successful up-and-down test of its “Hopper” developmental rocket vehicle.