Posted: Feb 24, 2020 10:16 pm
He knew that 5,000 feet was insufficient to achieve his objective. He wasn't a complete numpty (he already had got off the ground and returned successfully in contraptions of his own devising): This would be best understood as a test flight.
Would flat-Earth-believer Hughes have been able to see our planet's sphere at 5,000 feet (1,524 m)? Nope. And he knew that, saying he would need to soar past the so-called Kármán line — where the sky ends and space begins, or roughly 62 miles (100 kilometers) above Earth — to see the curvature with his own eyes.
To do that, Hughes told the Associated Press in 2018 that he wanted to build a "Rockoon," or rocket/gas-balloon-hybrid. That, he said, would let him float high into the atmosphere before lighting the rocket's fuse to boost him even farther into the air.