Perhaps the most significant point about the lunar-orbit flight proposed for Apollo 8 was that the command and service modules would fly the same route to the moon as would be used for the actual lunar landing.
An ‘A’ type mission would be flown with a Saturn V and be used to test the Launch vehicle, spacecraft, and a high velocity lunar return. Nasa cover the ‘A’ mission with Apollo 4 & 6.
A ‘B’ type mission would be flow with a Saturn IB and test the lunar module development, and propulsion, and launch vehicle staging. This was accomplished with Apollo 5.
A ‘C’ type mission would be flown with a Saturn IB and test the command and service module and evaluate the crew performance in low earth orbit. This was accomplished with Apollo 7…
CAPCOM Number 1 (Deke Slayton): Okay. I think you ought to clearly understand there is absolutely no experience at all with landing without the helmet on.
SCHIRRA: And there no experience with the helmet either on that one.
CAPCOM: That one we’ve got a lot of experience with, yes.
SCHIRRA: If we had an open visor, I might go along with that.
CAPCOM: Okay. I guess you better be prepared to discuss in some detail when we land why we haven’t got them on. I think you’re too late now to do much about it.
SCHIRRA: That’s affirmative. I don’t think anybody down there has worn the helmets as much as we have.
SCHIRRA: We tried them on this morning.
CAPCOM: Understand that. The only thing we’re concerned about is the landing. We couldn’t care less about the reentry. But it’s your neck, and I hope you don’t break it.
SCHIRRA: Thanks, babe.
CAPCOM: Over and out
SCHIRRA: You’ve added two burns to this flight schedule, and you’ve added a urine water dump; and we have a new vehicle up here, and I can tell you at this point TV will be delayed without any further discussion until after the rendezvous.
CAPCOM (Jack Swigert): Roger. Copy.
CAPCOM 1 (Deke Slayton): Apollo 7, this is CAPCOM number 1.
CAPCOM 1 (Slayton): All we’ve agreed to do on this is flip it.
SCHIRRA: the first part garbbled then Schirra said… with two commanders, Apollo 7
CAPCOM 1- (Slayton): All we have agreed to on this particular pass is to flip the switch on. No other activity is associated with TV; I think we are still obligated to do that.
SCHIRRA: We do not have the equipment out; we have not had an opportunity to follow setting; we have not eaten at this point. At this point, I have a cold. I refuse to foul up our time lines this way.