Missing a flight in a dream typically reflects the fear of a chance slipping past you while you're still getting ready for it -- feeling one step behind a deadline, a decision, or a version of your life you thought you'd have reached by now. The frantic run through the terminal is usually the real feeling on display.
The best artist in the world may chance to err, when he mistakes a true significator for a false one. - William Lilly (1602.-1681.)