The Landing That Almost Didn’t Happen

On July 20, 1969, Neil Armstrong and Buzz Aldrin were descending to the Moon in the lunar module Eagle when the computer began flashing 1202 and 1201 alarms. In Houston, engineer Jack Garman told Guidance Officer Steve Bales it was safe to keep going.

Then Armstrong saw that the computer was taking them towards an area strewn with boulders. He took semi-automatic control and flew on, looking for a clear place to land, while the fuel ran low.

In Houston, CapCom Charlie Duke called out “60 seconds,” then “30 seconds,” counting down to the “Bingo” fuel call. Then came Armstrong’s voice: “Houston, Tranquility Base here. The Eagle has landed.” Duke answered: “You got a bunch of guys about to turn blue.”

At the time, Mission Control believed Eagle had about 25 seconds of fuel left. Later analysis showed it was probably closer to 50.

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Fact check

The facts and where they come from

On July 20, 1969, Armstrong and Aldrin descended to the Moon in the lunar module Eagle. 1
The guidance computer threw several unexpected 1201 and 1202 program alarms; engineer Jack Garman told Guidance Officer Steve Bales it was safe to continue. 1
Armstrong saw the computer was targeting a boulder-strewn area and took semi-automatic control. 1
At landing, Mission Control believed there was enough fuel for about 25 more seconds of powered flight; post-mission analysis showed it was probably closer to 50 seconds. 1
Duke called “60 seconds” at 102:45:02 and “30 seconds” at 102:45:31 mission time, both counting down to the “Bingo” fuel call. 2
At 102:45:58 Armstrong said, “Houston, Tranquility Base here. The Eagle has landed.” At 102:46:06 Duke replied, “You got a bunch of guys about to turn blue.” 2 1

Sources

Apollo 11 Wikipedia
The First Lunar Landing Apollo Lunar Surface Journal

Notes

“Thirty seconds” was Duke’s call counting down to the Bingo fuel call, not to an empty tank.

Photo credits

The archive photos in this story

All the photographs and illustrations in this story are in the public domain. Tap one to enlarge it, or follow the link to its Wikimedia Commons page for the full record. The narration, music, captions and graphics in the Short are our own.