The Apollo 10 mission was practically perfect. And as the dress rehearsal for man’s landing on the moon two months later, it had to be.
The crew--Commander Thomas Stafford, Command Module Pilot John Young, and Lunar Module Pilot Eugene Cernan--were to reach the moon’s orbit and take the Lunar Module to within a few nautical miles of the surface.
They succeeded. And in July, history was made when Apollo 11 touched down.
A few minutes later, a sight that changed the world forever.
The famous words--"One small step for man, one giant leap for mankind"--those famous steps, that moment etched into the very pinnacle of human achievement owed itself to all that came before it, but no mission moreso than Apollo 10, the dress rehearsal that was practically perfect.
Everything had been a success, from the planning to the execution to the lunar descent that made history possible. Naturally, there were a few bumps along the way: The module unexpectedly rolled a little bit and live network broadcasts caught Cernan and Stafford swearing as they tried to get it under control.
But these were mundane and expected. Minor things go wrong all the time. For example, during preparation for Apollo 10, the Number 2 oxygen tank was dropped two inches while it was removed for modification. The tank’s internal fill line was slightly jarred, but it wasn’t a big deal at all. The tank was replaced and put back into storage.
History was made two months later and the world celebrated, while no one gave a second thought to the minor, mundane problems that all Apollo missions had.
Until 50 years ago today, when the world heard perhaps the Apollo missions’ second most famous words.
There had been an explosion onboard. Suddenly the crew of the Apollo 13 was in grave danger. The oxygen that they had been using to power their command module and, more pressingly, to breathe, was being vented into space. Thinking quickly, they worked with NASA engineers on the ground and escaped in the lunar module before splashing down safely in the Pacific Ocean three days later.
Only months afterward did NASA discover the problem: Oxygen Tank Number 2—the same one that had been damaged before the Apollo 10 mission. It had been loaded onto Apollo 13, but no one noticed that its fuel line was cracked, which caused the explosion.
That tiny oversight, that minor, mundane thing that went wrong a year earlier—the sort of thing that was expected and summarily brushed off—had become the one of the most pressing emergencies in the history of space flight.