HOUSTON — He’s a living American legend, immortalized in Hollywood film.  From inside mission control, former NASA flight director Gene Kranz helped land American men on the moon.

Fifty years after the historic Apollo 11 landing, Kranz returned to the room where humanity’s greatest feat unfolded.

Kranz was already a rising star at NASA when he heard President John F. Kennedy challenge the nation, saying “We choose to go to the moon not because it is easy, but because it is hard.”

“Kennedy’s speech ignited the fire,” said Kranz. “Let’s go do it.”

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But the journey to the moon was paved with setbacks. In 1967, a flash fire engulfed the Apollo 1 command module, killing 3 astronauts.

It was a moment that changed everything.

“If we want to go to moon we knew we were going to lose people. It happened in launch pad and now basically its up to us to get this program working again,” he said.

Moving forward, Kranz demanded perfection from Mission Control. And two years later, on July 16, 1969, Kranz watched Apollo 11 blast off into space. Four days later, on July 20,  Kranz and his team of controllers walked into mission control with a lunar landing within reach.

“Nobody can come in or out until we’ve landed crashed or we’ve aborted.   Those are the only 3 outcomes… between me and my team.. .these are the only people that exist in the universe”

For the next few hours, the Apollo 11 astronauts faced daunting challenges. Mission control worked each problem.  Every solution got them closer to the surface of the moon.  The Eagle landed with just 47 seconds of fuel left in the tank.

“The people in the viewing room are stomping and cheering right on down the line,” said Kranz.

The world celebrated, but Kranz and his crew still had work to do.

“We celebrated two hours after the landing,” he said.  “I really finally looked up could see the moon could see the thing up there and said hey we just landed on the moon. That’s pretty cool”

The success of Apollo 11 was way more than cool. It remains the defining moment in human history.

“People started believing in themselves and what they can do,” said Kranz.

Now at 85 years old, Kranz still finds himself captivated by the moon and its mystery. This NASA giant believes the moon is still calling.

“To me, it’s out there and its basically says, ‘I’m still here. Come and get me.’”