Requirements were so tight that airlines enforced rules which would probably be frowned upon now.
According to Vanity Fair, there were a few aesthetic rules that airline hopefuls had to fit into.
These include both weight and height guidelines, meaning women who weighed over 140 pounds were not permitted to take on the role.
A source told Vanity Fair: “The prerequisites were largely the same no matter which airline you hoped to fly for: with rare exceptions, you needed to have two X chromosomes; to be no younger than 20 and no older than 27; to be no shorter than five feet two inches or taller than five feet nine inches; to have a slender, “well-proportioned” figure (as a United recruiter once explained, “We are not looking for the Jayne Mansfield type”); to not, in any case, weigh more than 140 pounds; to agree to retire at the age of 32; to not currently be married (though it was permissible to be widowed or divorced); to not have children; and to absolutely, positively not be pregnant.
“In short, you needed to be both desirable and, at least in theory, available.”