Blue Origin is testing the engine in preparation for its use in the company’s New Glenn rocket as well as United Launch Alliance’s semi-reusable Vulcan rocket. Both launch vehicles are currently due to make their debut late this year. The BE-4, which uses liquefied natural gas for fuel, was developed at Blue Origin’s headquarters in Kent, Wash., with tests conducted at Bezos’ West Texas ranch (which is one of his pandemic hangouts). Last year, Blue Origin opened up a factory in Alabama to turn out rocket engines on a production basis. Each BE-4 is designed to blast out up to 550,000 pounds of thrust — or about 10% more thrust than SpaceX’s methane-fueled Raptor engine.