That is one great outfit and illustration. The "flash" of plaid from the coat is perfect.These illustrations are from Esquire, February 1943
Love the bold herringbone suit and I want the briefcase with the travel stickers (there's a better / more accurate name for them, but can't think of it now - anyone?).
However, I suggest he change his travel plans from flying to taking the train as he had two non-stop luxury train options to Chicago then: The 20th Century Limited or The Broadway Limited.