On February 26, 1966, NASA launched its new Saturn IB rocket on its first test flight. Also known as the Uprated Saturn I, the Saturn IB was built for the Apollo program. With a more powerful upper stage, it was designed to carry the Apollo Command/Service Module and Lunar Module into low-Earth orbit. NASA used the Saturn IB for flight tests early on in the Apollo program, but this type of rocket never actually launched astronauts to the moon. For that, they used an even more powerful rocket, the Saturn V. The first flight of the Saturn IB was uncrewed. Among other things, the mission tested the rocket's propulsion, guidance and electrical systems.