Probably it’d have been faster, cheaper but not better!
Right up to the end of the Gemini program, the Gemini spacecraft was considered by its contractor and certain factions within NASA as an alternate means of reaching the moon. The Gemini re-entry capsule, smaller and lighter than that of Apollo, would allow the direct launch of a mission to the moon using a single rocket.
Apollo is the way, however…
On July 11, 1962, NASA Administrator James Webb made public NASA’s plans! A LOR (Lunar Orbit Rendezvous) Apollo mission would have left the Earth on a Saturn C-5 (as the Saturn V rocket was known at the time), capable of launching 45 tons to the Moon, and the agency would also have studied a two-man Direct Ascent Apollo lunar landing mission also launched on a Saturn C-5. Direct Ascent means that a single spacecraft would carry the astronauts from Earth to the lunar surface and back again.
Webb did not provide a justification for this solution, though it soon became clear that it was a concession to Jerome Wiesner, chairman of the President’s Science Advisory Council (PSAC) which did not trust LOR’s complexity!
What plan do they choose? LOR or Direct Ascent?
During the spring of 1964, using a Saturn 1 rocket for Apollo flights was canceled, instead, the idea of utilizing Saturn 1 to launch a Gemini capsule around the moon was studied.
This could either be flown in the long gap between the end of Gemini and the start of Apollo/Saturn 1B flights or as a contingency to beat the Russians around the moon if Apollo suffered severe delays. But Von Braun and others were not interested in Congress getting wind of anything that could undermine support for Apollo. On June 8 NASA headquarters instructed that “any circumlunar mission studies related to the use of Gemini will be confined to in-house study efforts” and prohibited the issuance of contracts to McDonnell to pursue the matter!
In the wake of the Apollo 1 fire, NASA reexamined many safety aspects of the Apollo project. The Apollo mission profile was inherently risky, and the likelihood of a crew being stranded in lunar orbit or on the lunar surface was relatively high.
McDonnell returned to a concept first studied in 1962: the use of Gemini as a Lunar Rescue Vehicle. Use of the Gemini B capsule, then in construction for use with the US Air Force’s Manned Orbiting Laboratory, with various combinations of Apollo lunar module stations, would provide a rescue vehicle that could pick up Apollo astronauts stranded in lunar orbit or on the lunar surface.
McDonnell concluded that an unmanned “Gemini Universal Lunar Rescue Vehicle” could be developed that would perform all three tasks.
The Gemini capsule would be extended to allow up to three rescued Apollo crew members to be returned. Such a craft could rescue the entire Apollo crew at any point along the Apollo mission profile.
Some sketches appear to show a two-man Gemini crew in addition to three crew couches in the Gemini capsule extension. The unspoken point was that Saturn V was in fact large enough to land men on the moon using the direct-ascent method.
The use of lunar orbit rendezvous was only necessary because of NASA’s adherence to the 6-metric ton, three-crew Apollo command module design. The 2 metric ton Gemini capsule, even in a form stretched to accommodate three to five crew, could accomplish a direct landing on the moon using Apollo components.
Lunar Gemini is no longer an option
This last attempt to resuscitate Lunar Gemini failed as well!
At that point in the Apollo program cut-backs already had begun. No funds would be forthcoming to build additional launch vehicles and spacecraft beyond those already purchased. There was definitely no money to provide a rescue capability using either Apollo or Gemini hardware.
Not considered at the time, but truly having the potential for a reduced-cost, the reduced-risk program would have been a purely Titan-based, USAF-managed project. By using earth-orbit rendezvous and Titan 2 and Titan 3C as the launch vehicles, a program can be constructed that would have landed an American on the moon much earlier than Apollo. With a 2,500 kg open-cockpit LM the moon landing could be accomplished using only two Titan 3 launches: one a Titan 3E, putting a Centaur upper stage into low earth orbit; the other a Titan 3D, putting a Lunar Gemini-LM combination into low earth orbit, which would dock with the Centaur and then proceed to the moon.
Again: faster, cheaper but…
So in the end, the first lunar landing would have been moved up by six months at best. There would have been cost savings, but again analysis of the detailed cost breakdowns for Apollo indicates the savings would have been on the order of ‘only’ $4 billion out of the NASA $18 billion project share. So in retrospect, it would seem that NASA’s management was correct, for the Apollo missions flown were much more capable than a Gemini-based approach would have been!