First appearance of Hawkgirl in All Star Comics 5 (1941)
Extra wings
Where did Carter get any set of wings?
Solution
He was a scientist
Who invented them
(And a antique weapons collector)
How convenient
Then he realizes he was reincarnated
Both DCUI Library and Comixology Flash 1 (1940) only contain Flash story. NOT the Hawkman and Sierra first appearance.