Interesting article on Bleeding Cool... apparently the first appearance of Superman's ability to fly wasn't the 1940 radio show, but instead a 1939 British comic called Triumph.
[img]https://mlpnk72yciwc.i.optimole.com/w:600/h:843/q:auto/https://www.bleedingcool.com/wp-content/uploads/2019/06/triumph-772.jpg[/img]
[url]https://www.bleedingcool.com/2019/06/15/believe-superman-could-fly-in-1939/[/url]