Fifty Years Ago: Apollo 10 ‘a Great Amount of Teamwork’

Less than three weeks before their mission, Apollo 10 astronauts Thomas P. Stafford, Eugene A. Cernan and John W. Young met with the press on April 26, 1969, at NASA’s Manned Spacecraft Center (MSC) in Houston, now Johnson Space Center. The trio described their upcoming flight to the assembled reporters, which essentially would be a dress rehearsal for the Moon landing. Once in lunar orbit, Stafford and Cernan, aboard their Lunar Module (LM) “Snoopy,” would descend to about 50,000 feet above the Moon’s surface and photograph the primary landing site for Apollo 11: the Sea of Tranquility. Snoopy would travel up to 350 miles from Young in the Command and Service Module (CSM) “Charlie Brown” during these maneuvers. Simulating a litfoff from the Moon, Stafford and Cernan would then complete a rendezvous and docking with Young in the CSM.     

Apollo 10 crew members (left to right) Thomas Stafford, Eugene Cernan (with mascot Snoopy) and John Young at crew press conference on April 26. Image Credit: NASA

As part of that inspection, they would take stereo photographs to obtain the highest-resolution images of the site. They would also activate the LM’s landing radar during the low passes, a critical test before the Moon landing.

Regarding the complexity of the mission, Cernan said, “I’ve never been involved in anything that has required as great an amount of coordination and team work as … to work with two vehicles in a lunar environment.” 

Left: Apollo 10 astronauts (left to right) Stafford, Cernan and Young stand in front of their Saturn V rocket at Launch Pad 39B. Right: Apollo 10 astronauts receive a briefing on lunar topography from geologist and astronaut Harrison Schmitt (second from left).

When not speaking with the press, Stafford, Cernan and Young spent time—nearly daily—in the LM and Command Module simulators, rehearsing various aspects of their upcoming mission. During many of these simulations, mission control in Houston was tied in to give flight controllers practice. The astronauts also spent time reviewing procedures, updating checklists and receiving briefings on spacecraft systems and lunar topography.

Managers from NASA Headquarters, Kennedy Space Center, MSC and the Marshall Space Flight Center met at Kennedy on April 23 to conduct the Flight Readiness Review for Apollo 10. At the conclusion of the meeting, during which they reviewed all aspects of the flight hardware, as well as the readiness of the crew, the control centers and the Manned Spaceflight Network, the managers decided that the mission was ready to proceed with a launch on May 18. The Countdown Demonstration Test, a final dress rehearsal of the countdown, was scheduled to be conducted between April 29 and May 6, with the three crewmates participating in the final phase as if on launch day.

Even as the Apollo 10 flight approached launch, NASA was preparing for the Moon-landing mission, Apollo 11, planned for July. While test flights with NASA pilots continued with the Lunar Landing Training Vehicle (LLTV) at Ellington Air Force Base near MSC, Apollo 11 crew members made use of the Lunar Landing Research Facility at the NASA’s Langley Research Center in Virginia to train for the final descent to the lunar surface.

Backup Commander James A. Lovell and backup LM Pilot Fred W. Haise practiced Moon landings in the Lunar Landing Research Facility in mid-April. Prime crew Commander Neil A. Armstrong and prime LM Pilot Edwin E. “Buzz” Aldrin would use the facility for practice landings in late June. Once the LLTV was cleared for astronaut training in early June, Armstrong and Lovell completed training flights in that higher-fidelity vehicle later that month. Because the LLTV was a single-seat vehicle, and there was limited time available for training, only prime and backup commanders trained with it, while the Lunar Landing Research Facility was available to both commanders and LM pilots.

At MSC, Armstrong, Aldrin, Lovell and Haise each completed sea-level runs in Chamber B of the Space Environment Simulation Laboratory (SESL). During these tests, the astronauts wore their spacesuits and practiced various activities of the lunar surface Extravehicular Activity, or spacewalk, such as activating the TV camera, collecting rock samples and deploying the scientific experiments of the Early Apollo Surface Experiment Package (EASEP). They followed up these ambient sessions with altitude runs in early May.

NASA was even looking beyond the first landing, making preparations for Apollo 12, the second Moon landing expected to occur about four months after the first. Hardware for this mission had begun to arrive at Kennedy in March, including the Saturn V rocket’s S-II second and S-IVB third stages, the LM and the CSM. The Apollo 12 crew of Charles “Pete” Conrad, Alan L. Bean and Richard F. Gordon, announced in early April, was already in training and preparing for the first geology field trip to Hawaii in early May.    

Left: The Apollo 12 LM ascent stage is lowered onto the CSM in Kennedy’s altitude chamber for a docking test. Middle: The Apollo 12 S-IVB third stage arrives at Kennedy. Right: The Apollo 12 S-II second stage is wheeled into the Vehicle Assembly Building. Image Credits: NASA

Don't Forget: Relive Apollo 10 and Connect with NASA's Return to the Moon on April 25

As NASA heads to the Moon, an Apollo legend with real-other-world experience will share his stories from the Apollo 10 mission, which orbited the Moon to “sort out all the unknowns and actually pave the whole way for the lunar landing mission.”