An expression is developed for the landing capacity (or service rate) of a single runway in which aircraft are restricted by a minimum space separation at the beginning of a common approach glide path and by a minimum time separation at the runway. The conditions at any terminal may be inserted to determine its characteristic landing capacity. Single runways at the New York area terminals are shown to have landing capacities of 30–40 landings per hour. It is shown that the greatest improvement in the present landing rate can be achieved by reducing the separation at the beginning of the common path, and that little is gained by reducing only the time separation at the runway.