The U.S. Air Force Research Laboratory and contractor Aerojet Rocketdyne achieved a major milestone under the Hydrocarbon Boost programme, which is advancing U.S. rocket engine technologies in support of next generation launch. The Hydrocarbon Boost (HCB) programme completed full power, full duration tests of the oxygen-rich staged combustion (ORSC) sub-scale preburner. Testing was conducted at the historic rocket Test Stand 2A at Edwards Air Force Base.