People used to think of the speed of sound as a kind of physical barrier, a brick wall that

just couldn't be approached by humans without catastrophic consequences.

But then in 1947, Chuck Yeager, flying the Bell X1, broke the sound barrier.

You know, ignorance. People really just didn't know it was ignorance. They thought an airplane would never go faster than sound because of the shock waves that built up on it, but that really didn't make any difference to me. I could care that it's your job to try it. It's duty. It's just like flying combat.

You know, you go on a combat mission, somebody's going to get killed. You just hope it isn't

you, but if it is, that's where it goes. The same way with

flying the X1. It didn't make any difference to me whether I thought the airplane would

go fast and sound. I was signed as a test pilot on it and it was my duty to fly.

Chuck Yeager's death-defying feet transformed aviation and ushered in the era of modern spaceflight.

Yeager turns 96 years old in a few weeks,

and we celebrate his birthday with this episode of What It Takes, a podcast about passion, vision, and perseverance from the

audio vault of the Academy of Achievement.

I'm Alice Winkler.

Adam Aye, this child is gifted.

And I heard that enough that I started to believe it.

If you have the opportunity, not a perfect opportunity,

and you don't take it, you may never have another job.

It all was so clear. It was just like the picture started to form itself.

There was no way in which a lie could prevail over the truth, darkness over light, death over life.

Every day I wake up and decide. Today I'm going to love my life. Decide.

My advice is if they don't break your leg once when you go in that place stay out of there.

And then along come these differential experiences that you don't look for, you don't plan for,

...