To more clearly illustrate how the elements of the airport system function we organized them into three primary categories: vehicles, people, and aircraft. These categories represent the modes that use the various ways or elements of the airport system, be it a private automobile accessing the airport via the internal roadways, a pedestrian navigating on foot through a terminal concourse, or an aircraft taxiing to a runway.
Ownership of these elements is quite complex. As you can see in the diagram, a number of these elements overlap, with the Port Authority sharing responsibility for several of the landside and airside components with both the commercial airlines and the Federal Aviation Administration. Ground access is one of the most complex institutional arrangements with numerous agencies responsible for adjacent roadways and rail access.
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