Winston
Lorenzo von Matterhorn
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The Apollo Program was an absolutely GARGANTUAN, incredibly complex and challenging one and a huge accomplishment, but there was some luck involved, too. The superb crews and support personnel on the ground overcame all of the bad luck.
MAY 21, 2019
When Apollo 10 Nearly Crashed Into the Moon
The mission that paved the way for the Apollo 11 moon landing came close to ending in disaster.
https://www.history.com/news/apollo-10-disaster-apollo-11-practice-run
Commander Tom Stafford and Lunar Module Pilot Gene Cernan had just returned from their close pass by the lunar surface and were readying to go through the staging maneuver that would bring them into the correct lunar orbit to rejoin Command Module Pilot John Young waiting in the Command-Service module. On schedule, the LM’s ascent engine fired.
Then all hell broke loose.
The crew saw the lunar horizon swivel past their window half a dozen times as Cernan yelled out “Son of a bitch!” Apollo 10’s lunar module, with two astronauts on board, was careening out of control a quarter of a million miles from home. ["SOB" came up more than once in the audio link. See transcript link below. - W]
Stafford moved a switch from the Safe position to Stage, activating the small explosives that forcibly separated the ascent stage from the descent stage. But rather than a smooth flight, the spacecraft started gyrating wildly, rolling, pitching and yawing around all three axes in turn. Almost instantly, Stafford saw a yellow Gimbal Lock light illuminate on a nearby instrument panel. The computer was close to losing its orientation in space, which would mean the crew could have no idea where they were and how to get home.
“Son of a bitch!” Cernan yelled as they got a quick sight of the separated descent stage passing by a window.
“We’re in trouble,” Stafford concurred.
The spacecraft never went into gimbal lock. Stafford reacted quickly and began manually correcting the spinning and rolling to get the spacecraft back into the correct attitude for their continued ascent. Less than four minutes after the initial staging, everything had calmed down.
“I think we have got all our marbles,” Stafford called down to Houston.
It was only later that the crew learned exactly what had happened. A series of small errors on the crew's part had left the LM’s guidance system pointing in the wrong direction. An errant setting in the spacecraft left the LM’s abort-guidance system searching for the CSM at a time when it shouldn't have been, and since it wasn’t near where the crew was aiming, it sent them on their frightening spin.
Apollo 10
Day 5 part 20: A surprise at staging
Corrected Transcript and Commentary Copyright © 2015 by David Woods, Robin Wheeler and Ian Roberts. All rights reserved.
Last update: 2017-02-10
https://history.nasa.gov/afj/ap10fj/as10-day5-pt20.html
MAY 21, 2019
When Apollo 10 Nearly Crashed Into the Moon
The mission that paved the way for the Apollo 11 moon landing came close to ending in disaster.
https://www.history.com/news/apollo-10-disaster-apollo-11-practice-run
Commander Tom Stafford and Lunar Module Pilot Gene Cernan had just returned from their close pass by the lunar surface and were readying to go through the staging maneuver that would bring them into the correct lunar orbit to rejoin Command Module Pilot John Young waiting in the Command-Service module. On schedule, the LM’s ascent engine fired.
Then all hell broke loose.
The crew saw the lunar horizon swivel past their window half a dozen times as Cernan yelled out “Son of a bitch!” Apollo 10’s lunar module, with two astronauts on board, was careening out of control a quarter of a million miles from home. ["SOB" came up more than once in the audio link. See transcript link below. - W]
Stafford moved a switch from the Safe position to Stage, activating the small explosives that forcibly separated the ascent stage from the descent stage. But rather than a smooth flight, the spacecraft started gyrating wildly, rolling, pitching and yawing around all three axes in turn. Almost instantly, Stafford saw a yellow Gimbal Lock light illuminate on a nearby instrument panel. The computer was close to losing its orientation in space, which would mean the crew could have no idea where they were and how to get home.
“Son of a bitch!” Cernan yelled as they got a quick sight of the separated descent stage passing by a window.
“We’re in trouble,” Stafford concurred.
The spacecraft never went into gimbal lock. Stafford reacted quickly and began manually correcting the spinning and rolling to get the spacecraft back into the correct attitude for their continued ascent. Less than four minutes after the initial staging, everything had calmed down.
“I think we have got all our marbles,” Stafford called down to Houston.
It was only later that the crew learned exactly what had happened. A series of small errors on the crew's part had left the LM’s guidance system pointing in the wrong direction. An errant setting in the spacecraft left the LM’s abort-guidance system searching for the CSM at a time when it shouldn't have been, and since it wasn’t near where the crew was aiming, it sent them on their frightening spin.
Apollo 10
Day 5 part 20: A surprise at staging
Corrected Transcript and Commentary Copyright © 2015 by David Woods, Robin Wheeler and Ian Roberts. All rights reserved.
Last update: 2017-02-10
https://history.nasa.gov/afj/ap10fj/as10-day5-pt20.html
