The abort system had two basic control modes, “attitude hold” and “automatic.” In automatic, the computer would take over the guidance and start looking for the command module, which was certainly not what the crew intended to do at that moment. While correcting for a minor yaw-rate-gyro disturbance, the astronauts accidentally switched the spacecraft to the automatic mode, resulting in frantic gyrations.
The six-minute retrograde maneuver seemed interminable, just as it had to Borman’s crew on Apollo 8, but the engine kept firing and the Apollo 10 crew’s confidence in it kept growing. When the engine finally shut down and they were sure that it had done its job, Stafford and Cernan had time to look at the lunar surface. They likened one area to a volcanic site in Arizona. Shortly, Stafford forced his attention back inside the cabin and told his crew-mates that he thought the best thing to say when they got back in radio contact with mission control was, “Houston, tell the earth we have arrived.”
Stafford, Cernan, and Young were the first Apollo astronauts to be free from illness during the mission, although Cernan experienced a slight vestibular disturbance. Like all their colleagues who had flown before, once they unbuckled from the couches they had a stuffy feeling in their heads. This lasted for 8 to 10 hours for Stafford and Young; Cernan gradually lost the sensation over the next two days.
On May 18th 1969, a king, some congressmen, other distinguished guests, and a hundred thousand other watchers waited at scattered vantage points around the Cape area. At 49 minutes past noon, Rocco Petrone’s launch team sent Apollo 10 on its way to the United States’s second manned rendezvous with the moon.
John Young enjoyed the longest career of any astronaut thus far. Over the course of 42 years of active NASA service he made six space flights and is the only person to have piloted, and been commander of, four different classes of spacecraft: Gemini, the Apollo Command/Service Module, the Apollo Lunar Module, and the Space Shuttle.
Thomas P. Stafford was the first member of his Naval Academy Class of 1952 to pin on the first, second, and third stars of a General Officer. He flew six rendezvous in space; logged 507 hours and 43 minutes in space flight and wore the Air Force command Pilot Astronaut Wings. He has flown over 127 different types of aircraft and helicopters and four different types of spacecraft.
Although the contractors had shipped excellent spacecrafts, preparations at Kennedy did not go quickly from the assembly building to the launch pad. Testing was delayed several days in order to stay out of the way of Apollo 9 pre-flight activities. Also during maintenance to the Launch Control Center, the electrical power was switched off to replace a valve. The Apollo 10 launch vehicle’s pneumatic controls sensed the power outage, opened some valves and dumped 20,000 liters of fuel on the launch pad.