See listJAN 18 196767-FM1-6FM/Deputy Chief, Mission Planning and Analysis DivisionAS-504 Spacecraft Computer Programs will be able to support earth orbital and lunar missions
At one time I had sort of expected that we would have to maintain two basic programs for each of the Apollo spacecraft – one for earth orbital operations and one for lunar operations. The former would probably be a refinement of the AS-258 programs and the latter of the AS-504 pro- grams. Further investigation, primarily by Norm Sears of MIT, has re- vealed that it should be possible to develop spacecraft programs for the lunar mission which will also handle earth orbital missions of at least the AS-258 complexity. Accordingly, it is our intention to develop the AS-504 programs in this way for use on all main line Apollo flights after AS-503. They will be designed to even permit execution of alter- nate mission plans as a result of contingency situations occurring during the operation. That is, the earth orbital versus lunar option can be exercised in-flight as well as pre-flight.
This new capability provides a considerable flexibility as well as allow- ing us to exercise the lunar mission programs in earth orbit. Since it is somewhat of a departure from our original plans, I thought it would be worthwhile to tell you about it.