I too like "It's time to fly."

It does drag in everything else that people associate with flying, though, which can be good or bad. As in, "It's time to wait for your delayed flight, and miss your family, and have no legroom, and listen to crying babies, and be groped by the TSA, and whatever else bothers me about traveling." But for me it means "It's time to break up my normal routine, see someplace new, visit friends and family all around the country and the world, and accumulate program points and miles that I value out of proportion to their actual monetary value."