|astronautix.com||Selection of LOR as Apollo Mission Mode|
Following a long controversy NASA selected Lunar Orbit Rendezvous (LOR) as the fastest, cheapest, and safest mode to accomplish the Apollo mission. LOR solved the engineering problem of how to land. The EOR or Direct Landing approaches required the Apollo crew to be on their backs during the landing and having to use television or mirrors to see the lunar surface. A lunar crasher stage approach had finally emerged as lesser of evils but raised other issues. LOR allowed a purpose-built lander with a logical helicopter-like crew station layout. Studies indicated LOR would allow landing 6-8 months earlier and cost $9.2 billion vs $ 10.6 billion for EOR or direct. Direct flight by this time would not involve Nova, but a scaled-down two-man spacecraft that could be launched by the Saturn C-5.
NASA officials announced at a Washington, D.C., press conference that the lunar orbit rendezvous (LOR) technique had been selected as the primary method of accomplishing the lunar landing mission. The launch vehicle would be the Saturn C-5, with the smaller two-stage Saturn C-1B (S-IVB as second stage) used in early earth orbital spacecraft qualification flights. Requests for industrial proposals would be issued immediately on the lunar excursion module, The reasons for the decision on lunar orbit rendezvous were explained: