Apollo 9 (March 3–13, 1969) was the third human spaceflight in NASA's Apollo program, which successfully tested systems and procedures critical to landing on the Moon. The three-man crew consisted of Commander James McDivitt, Command Module Pilot David Scott, and Lunar Module Pilot Rusty Schweickart. Flown in low Earth orbit, it was the second crewed Apollo mission that the United States launched via a Saturn V rocket, and was the first flight of the full Apollo spacecraft: the command and service module (CSM) with the Lunar Module (LM).
The mission was flown to qualify the LM for lunar orbit operations in preparation for the first Moon landing by demonstrating its descent and ascent propulsion systems, showing that its crew could fly it independently, then rendezvous and dock with the CSM again, as would be required for the first crewed lunar landing. Other objectives of the flight included firing the LM descent engine to propel the spacecraft stack as a backup mode (as was required on the Apollo 13 mission), and use of the portable life support system backpack outside the LM cabin.
After launching on March 3, 1969, the crew performed the first crewed flight of an Apollo Lunar Module, the first docking and extraction of the same, one two-person spacewalk (EVA), and the second docking of two crewed spacecraft—two months after the Soviets performed a spacewalk crew transfer between and . The mission concluded on March 13 and was a complete success. It proved the LM worthy of crewed spaceflight, setting the stage for the dress rehearsal for the lunar landing, Apollo 10, before the ultimate goal, landing on the Moon.
Mission background
In April 1966, McDivitt, Scott, and Schweickart were selected by Director of Flight Crew Operations Deke Slayton as the second Apollo crew. Their initial job was as backup to the first Apollo crew to be chosen, Gus Grissom, Ed White, and Roger Chaffee, for the first crewed Earth orbital test flight of the block I command and service module, designated AS-204. Delays in the block I CSM development pushed AS-204 into 1967. The revised plan had the McDivitt crew scheduled for the second crewed CSM, which was to rendezvous in Earth orbit with an uncrewed LM, launched separately. The third crewed mission, to be commanded by Frank Borman, was to be the first launch of a SaturnV with a crew.Brooks, et al. 1979, Chapter 8.7: "Preparations for the First Manned Apollo Mission" ()
On January 27, 1967, Grissom's crew was conducting a launch-pad test for their planned February 21 mission, which they named Apollo 1, when a fire broke out in the cabin, killing all three men. A complete safety review of the Apollo program followed. During this time Apollo 5 took place, an uncrewed launch to test the first lunar module (LM-1).
Under the new schedule, the first Apollo crewed mission to go into space would be Apollo 7, planned for October 1968. This mission, which was to test the block II command module, did not include a lunar module. In 1967, NASA had adopted a series of lettered missions leading up to the crewed lunar landing, the "G mission", completion of one being a prerequisite to the next.Ertel, Roland, & Brooks 1975, Part 2(D): "Recovery, Spacecraft Redefinition, and First Manned Apollo Flight" (). Apollo7 would be the "Cmission", but the "Dmission" required testing of the crewed lunar module, which was running behind schedule and endangering John F. Kennedy's goal of Americans walking on the Moon and returning safely to Earth by the end of the 1960s.Brooks, et al. 1979, Chapter 11.2: "Proposal for a lunar orbit mission" () McDivitt's crew had been announced by NASA in November 1967 as prime crew for the Dmission, lengthy testing of the command and lunar modules in Earth orbit.Brooks, et al. 1979, Chapter 11.3: "Selecting and training crews" ()
Seeking to keep Kennedy's goal on schedule, in August 1968, Apollo Program Manager George M. Low proposed that if Apollo7 in October went well, Apollo8 would go to lunar orbit without a LM. Until then, Apollo8 was the Dmission with Apollo9 the "E mission", testing in medium Earth orbit. After NASA approved sending Apollo8 to the Moon, while making Apollo9 the Dmission, Slayton offered McDivitt the opportunity to stay with Apollo8 and thus go to lunar orbit. McDivitt turned it down on behalf of his crew, preferring to stay with the Dmission, now Apollo9.
Apollo7 went well, and the crews were switched. The crew swap also affected who would be the first astronauts to land on the Moon, for when the crews for Apollo8 and9 were swapped, so were the backup crews. Since the rule of thumb was for backup crews to fly as prime crew three missions later, this put Neil Armstrong's crew (Borman's backup) in position to make the first landing attempt on Apollo 11 instead of Pete Conrad's crew, who made the second landing on Apollo 12.
Framework Crew and key Mission Control personnel
McDivitt was in the Air Force; selected as a member of the second group of astronauts in 1962, he was command pilot of Gemini 4 (1965). Scott, also Air Force, was selected in the third astronaut group in 1963 and flew alongside Neil Armstrong in Gemini 8, on which the first spacecraft docking was performed. Schweickart, a civilian who had served in the Air Force and Massachusetts Air National Guard, was selected as a Group3 astronaut but was not assigned to a Gemini mission and had no spaceflight experience.
The backup crew initially consisted of Pete Conrad as commander, Command Module Pilot Richard F. Gordon Jr., and Lunar Module Pilot Clifton C. Williams Jr.. After Williams died in a T-38 crash in October 1967, he was replaced by Alan L. Bean. This crew flew as prime on Apollo 12 in November 1969. The support crew for Apollo9 consisted of Stuart A. Roosa, Jack R. Lousma, Edgar D. Mitchell and Alfred M. Worden. Lousma was not an original member of the Apollo9 support crew, but was assigned after Fred W. Haise Jr. was moved to the position of backup lunar module pilot on Apollo 8—several astronauts were shifted in the wake of Michael Collins being removed from the Apollo8 prime crew because of treatment for bone spurs.
The flight directors were Gene Kranz, first shift, Gerry Griffin, second shift, and Pete Frank, third shift. Capsule communicators were Conrad, Gordon, Bean, Worden, Roosa and Ronald Evans.
Mission insignia
The circular patch shows a drawing of a Saturn V rocket with the letters USA on it. To its right, an Apollo CSM is shown next to a LM, with the CSM's nose pointed at the "front door" of the LM rather than at its top docking port. The CSM is trailing rocket fire in a circle. The crew's names are along the top edge of the circle, with APOLLO IX at the bottom. The "D" in McDivitt's name is filled with red to mark that this was the "Dmission" in the alphabetic sequence of Apollo missions. The patch was designed by Allen Stevens of Rockwell International. "A version of this article was published concurrently in the British Interplanetary Society's Spaceflight magazine."
Planning and training
Apollo 9's main purpose was to qualify the LM for crewed lunar flight, demonstrating that it could perform the maneuvers in space that would be needed for a lunar landing, including docking with the CSM. Colin Burgess and Francis French, in their book about the Apollo Program, deemed McDivitt's crew among the best trained ever—they had worked together since January 1966, at first as backups for Apollo 1, and they always had the assignment of being the first to fly the LM. Flight Director Gene Kranz deemed the Apollo9 crew the best prepared for their mission, and felt Scott was an extremely knowledgeable CMP. Crew members underwent 1,800 hours of mission-specific training, about seven hours for every hour they would spend in flight. Their training started on the day before the Apollo1 fire, in the very first Block II spacecraft in which they were originally intended to fly. They took part in the vehicle checkouts for the CSM at North American Rockwell's facility in Downey, California, and for the LM at Grumman's plant in Bethpage, New York. They also participated in testing of the modules at the launch site.
Among the types of the training which the crew underwent were simulations of zero-G, both underwater and in the Vomit Comet. During these exercises, they practiced for the planned extravehicular activities (EVAs). They traveled to Cambridge, Massachusetts, for training on the Apollo Guidance Computer (AGC) at MIT. The crew studied the sky at the Morehead Planetarium and at the Griffith Planetarium, especially focusing on the 37 stars used by the AGC. They each spent more than 300 hours in the CM and LM simulators at Kennedy Space Center (KSC) and at Houston, some involving live participation by Mission Control. Additional time was spent in simulators in other locations.
The first mission to use the CSM, the LM and a SaturnV, Apollo9 allowed the launch preparations team at KSC its first opportunity to simulate the launch of a lunar landing mission. The LM arrived from Grumman in June 1968 and was subjected to extensive testing including in the altitude chamber, simulating space conditions. As this occurred, other technicians assembled the SaturnV inside the Vehicle Assembly Building (VAB). The CM and SM arrived in October, but even the experienced KSC team from North American had trouble joining them together. When the lander was done with the altitude chamber, the CSM took its place, letting the LM be available for installation of equipment such as rendezvous radar and antennas. There were no lengthy delays, and on January 3, 1969, the launch vehicle was taken out of the VAB and moved to Launch Complex 39A by crawler. Flight readiness reviews for the CM, the LM, and the SaturnV were held and passed in the following weeks.Brooks, et al. 1979, Chapter 12.3: "A double workload" ()
Hardware Launch vehicle The Saturn V (AS-504) used on Apollo9 was the fourth to be flown, the second to carry astronauts to space, and the first to bear a lunar module. Although similar in configuration to the SaturnV used on Apollo 8, several changes were made. The inner core of the F-1 engine chamber in the first (S-IC) stage was removed, thus saving weight and allowing for a slight increase in specific impulse. Weight was also saved by replacing the skins of the liquid oxygen tanks with lighter ones, and by providing lighter versions of other components. Efficiency was increased in the S-II second stage with uprated J-2 engines, and through a closed-loop propellant utilization system rather than Apollo 8's open-loop system. Of the weight reduction in the second stage, about half came from a 16 percent reduction in the thickness of the tank side walls.
Spacecraft, equipment and call signs
Apollo9 used CSM-104, the third Block II CSM to be flown with astronauts aboard. Apollo 8, lacking a lunar module, did not have docking equipment; Apollo9 flew the probe-and-drogue assembly used for docking along with other equipment added near the forward hatch of the CM; this allowed for rigid docking of the two craft, and for internal transfer between CM and LM. Had the switch in missions between Apollo8 and9 not occurred, the Earth-orbit mission would have flown CSM-103, which flew on Apollo 8.