On this day in 1962, NASA announced plans to build the C-5. The three-stage rocket would consist of: the S-IC first stage, with five F-1 engines; the S-II second stage, with five J-2 engines; and the S-IVB third stage, with a single J-2 engine. The C-5 was designed for a 90,000 pounds (41,000 kg) payload capacity to the Moon.
The C-5 would undergo component testing even before the first model was constructed. The S-IVB third stage would be used as the second stage for the C-IB, which would serve both to demonstrate proof of concept and feasibility for the C-5, but would also provide flight data critical to development of the C-5. Rather than undergoing testing for each major component, the C-5 would be tested in an “all-up” fashion, meaning that the first test flight of the rocket would include complete versions of all three stages. By testing all components at once, far fewer test flights would be required before a manned launch.
The C-5 was confirmed as NASA’s choice for the Apollo program in early 1963, and was named the Saturn V.