Tucson-based small-satellite launch startup Vector has won a key U.S. patent for its small-rocket engine technology as it moves toward its first orbital flight later this year.
Vector was awarded patent number 10,072,612 on Sept. 11 for its “enhanced liquid oxygen-propylene rocket engine,” including a rocket-propellant injector made with 3-D metal printing and optimized to use propylene.
The patent covers some of Vector’s foundational technology, based on work by Vector co-founders John Garvey and Eric Besnard when Garvey was developing Garvey Spacecraft Corp. and Besnard was a professor at California State University, Long Beach.
The researchers found that using liquid oxygen with propylene, a hydrocarbon gas, provided the ideal combination of combustion efficiency and energy density.
When chilled, the propylene gas can be stored under pressure in a tank and fed to the engine directly, with much smaller fuel tanks and without fuel pumps normally used in rocket engines, Besnard said.
“That, combined with the recent advances in (3-D) printing technology, has really made this an enabler for this low-cost launch vehicle that we’re doing,” he said.
Vector’s business model is to serve a fast-growing market for launches of tiny nanosatellites for about $3 million per launch — a fraction of the price of a ride on a full-size rocket.
The use of 3-D metal printing, a form of so-called additive manufacturing, enables engine designers to build in complex features like curved holes that would otherwise require multiple parts, Besnard noted.
“You don’t have to make tens of parts that you have to weld together and test,” he said. “We’re able to have all kinds of curves and passages and orifices and all that, so that’s something very unique we’re able to do.”
Garvey and Besnard are named as co-inventors on the engine patent, along with Christopher Bostwick, Vector’s director of propulsion and former chief engineer at Garvey Spacecraft; and Christopher Anderson, a former Garvey mechanical engineer now working for Vector.