The Calm Lunar Landing of Apollo 12

Compared to Apollo 11’s lunar landing, interrupted by program alarms and worries about running out of fuel, Apollo 12’s pinpoint landing next to the crater where Surveyor 3 had landed on 1967-04-20, was remarkably uneventful. After having been struck by lightning shortly after launch, landing on the Moon seemed almost routine.

10 Likes

This is an incredible video!

Watching the P63 play by play it dawned on me that the humans in the control loop for landing were both on Earth at Houston Mission Control and onboard the lander. Yet the whole process plays out flawlessly (except for RCS “banging the LM around”).

This is like a blind driver parallel parking a car in San Francisco with a FaceTime session with his friend in New York city. Oh, and FaceTime is on the Apple Watch, and the camera does not really work.

The landing computer is so primitive that commands need to be checked and inputs calculated on Earth. They land with less than 10% of fuel left. Bean and Conrad were joking around like Southwest Airlines pilots on approach to NY JFK.

How did they pull this off? Is it just a matter of having the Right Stuff and nerves of steel, or? Do they make it look easy or what?

2 Likes

Very cool to see the camera video along with all the audio. They must have practiced this hundreds of times.

I recommend the book “Digital Apollo: Human and Machine in Spaceflight”, by David A. Mindell. This video makes me want to go back and re-read it.

2 Likes

This was considered “nominal” for Apollo landings. All of the margins were very small, and there was very limited time to choose a landing spot and set down. Apollo 11 landed with just about 1.2% of descent fuel remaining. Mission control estimated only 25 seconds of fuel remaining, but post-flight analysis indicated the measurement was low due to fuel sloshing and there were actually around 50 seconds left.

2 Likes