Apollo 8 - Planning

Planning

Apollo 4 and Apollo 6 had been "A" missions, unmanned tests of the Saturn V launch vehicle using an unmanned Block I production model of the Apollo Command and Service Module in Earth Orbit. Apollo 7, scheduled for October 1968, would be a manned Earth Orbit flight of the CSM, completing the objectives for Mission "C".

Further missions depended on the readiness of the Lunar Module (LM). Apollo 8 was planned as the "D" mission, to test the LM in a low Earth orbit in December 1968 by James McDivitt, David Scott and Russell Schweickart, while Borman's crew would fly the "E" mission, a more rigorous LM test in an elliptical medium Earth orbit as Apollo 9, in early 1969.

But production of the LM fell behind schedule, and when Apollo 8's LM arrived at Cape Canaveral in June 1968, significant defects were discovered, leading Grumman, the lead contractor for the LM, to predict that the first mission-ready LM would not be ready until at least February 1969. This would mean delaying the "D" and subsequent missions, endangering the program's goal of a lunar landing before the end of 1969.

George Low, the Manager of the Apollo Spacecraft Program Office, proposed a solution in August to keep the program on track despite the LM delay. Since the Command/Service Module (CSM) would be ready three months before the Lunar Module, a CSM-only mission could be flown in December 1968. Instead of just repeating the "C" mission flight of Apollo 7, this CSM could be sent all the way to the Moon, with the possibility of entering a lunar orbit. The new mission would also allow NASA to test lunar landing procedures that would otherwise have to wait until Apollo 10, the scheduled "F" mission. This also meant that the medium Earth orbit "E" mission could be dispensed with. The net result was that only the "D" mission had to be delayed.

Almost every senior manager at NASA agreed with this new mission, citing both confidence in the hardware and personnel, and the potential for a significant morale boost provided by a circumlunar flight. The only person who needed some convincing was James E. Webb, the NASA administrator. With the rest of his agency in support of the new mission, Webb eventually approved the mission change. The mission was officially changed from a "D" mission to a "C-Prime" Lunar Orbit mission, but was still referred to in press releases as an Earth Orbit mission at Webb's direction. No public announcement was made about the change in mission until November 12, three weeks after Apollo 7's successful Earth orbit mission and less than 40 days before launch.

With the change in mission for Apollo 8, Director of Flight Crew Operations Deke Slayton decided to swap the crews of the D and E missions. This swap also meant a swap of spacecraft, requiring Borman's crew to use CSM-103, while McDivitt's crew would use CSM-104.

On September 9, the crew entered the simulators to begin their preparation for the flight. By the time the mission flew, the crew had spent seven hours training for every actual hour of flight. Although all crew members were trained in all aspects of the mission, it was necessary to specialize. Borman, as commander, was given training on controlling the spacecraft during the re-entry. Lovell was trained on navigating the spacecraft in case communication was lost with the Earth. Anders was placed in charge of checking that the spacecraft was in working order.

Added pressure on the Apollo program to make its 1969 landing goal was provided by the Soviet Union's flight of some living creatures, including Russian tortoises, in a cislunar loop around the Moon on Zond 5 and return to Earth on September 21. There was speculation within NASA and the press that they might be preparing to launch cosmonauts on a similar circumlunar mission before the end of 1968.

The Apollo 8 crew, now living in the crew quarters at Kennedy Space Center, received a visit from Charles Lindbergh and his wife, Anne Morrow Lindbergh, the night before the launch. They talked about how, before his 1927 flight, Lindbergh had used a piece of string to measure the distance from New York City to Paris on a globe and from that calculated the fuel needed for the flight. The total was a tenth of the amount that the Saturn V would burn every second. The next day, the Lindberghs watched the launch of Apollo 8 from a nearby dune.