Hmm. I'm not totally sure that's how the whole thing went down, considering this quote that indicates Margaret Jackson likely has a talent for exaggeration (not to mention a hint of racial prejudice): "And I said, 'I'm the chairman of an airline. I'm the chairman of Qantas'. And this black guy, who was, like, eight foot tall*, said, 'But you're a woman'."
Plus, I would say if security personnel did not stop anyone, male or female, who was walking onto a plane with plane schematics, at least to make sure that person had a valid reason for carrying those schematics, that security guard would not be doing his or her job.
Also —and I admit this is a little nitpicky—she is not the chairman. That is an outdated term because it does, in fact, imply maleness. The correct term is chair. She is the chair of Qantas.
*Italics mine.