Later that day, Leonardo brought Johan to his house to start working on the wings. Johan sewed the wings, while Leonardo carved wood that would hold tiny wing to steer and they talked while they worked to get to know each other.
Once they finished the the wings they put their design to the test and the one testing it is Johan. He and Leonardo went up on the balcony to see if the their design worked. It did, Johan was gliding through the air, for about the next ten seconds and it ripped. Johan screamed in terror as he was about to hit the ground. But, miraculously,a gust of wind pulled him into a nearby river.
After their failed attempt and their invention being swept away at sea, Leonardo and Johan get new ideas and a new design like making the wings bigger and adding more straps for safety.
One week of new ideas and redesigning had passed, Johan and Leonardo test their new design and it works. But it only worked for a minute but, they were happy they made progress.
And for years to come they kept trying to make man-made wings.
Even long after Leonardo was gone and Johan carried on the project even though he never succeeded.