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Hydrogen-fueled engine for Delta IV Heavy Launch Vehicle passes final hot-fire acceptance test - NewsApril 12, 2021
NASA -- STENNIS SPACE CENTER, Miss. The powerful hydrogen-fueled rocket engine built by Aerojet Rocketdyne, the RS-68A, completed its final hot-fire acceptance test in preparation for its use on the United Launch Alliance (ULA) Delta IV Heavy launch vehicle.
ORLANDO, Fla. According to NASA officials, one of the most powerful rockets in service is scheduled to carry a classified spy satellite for the U.S. Department of Defense (DoD) aloft from Florida before dawn Thursday.