By definition an airport is a place where aircraft can land and take off. And, it so happens there are more than 5,000 public-use airports in the United States. Although most are categorized as nontowered, there are some 600 airports that have an operating air traffic control tower. Do you worry about communicating with the tower or do you have trepidation about self-announcing on the Unicom? Whether you’re new to these environments, or just need a review, this Safety Spotlight refreshes your knowledge and improves your airport etiquette.