F-1 is the most powerful U.S. rocket engine to be placed in production. Developed at Conoga Park, California, by Rocketdyne, a division of North American Aviation, Inc., under the technical direction of NASA's George C. Marshall Space flight Center, Huntsville, Alabama. F-1 was used in a cluster of five to provide 7,500,000 pounds of booster power for the Saturn vehicle that launched the Apollo manned spacecraft to the moon.