The success of the Apollo program was largely based on the performance of the Saturn V rocket with its five massive F-1 engines in the first stage, which were claimed to be the most powerful rocket engines ever built. However, in NASA's comprehensive 750-page Architecture Study, the F-1 engine is neither considered as a fall-back option nor analysed as a prototype for further development. It is only once vaguely mentioned in this detailed review of NASA's capabilities in rocket science and technology.