Runway is an important
component of an airport and the capacity of an airport depends upon its runway
configuration. The four basic types of runway are single runway, parallel
runways, intersecting runways and non-intersecting runways. Single runway is
the simplest format and is adopted if air traffic is less and wind blows in one
direction for most of the time in a year. It can provide about 40 operations
per hour. Parallel runways capacity depends upon the lateral spacing between
two runways. Weather conditions and the various navigational aids available at
the airport do affect the capacity of parallel runways. A minimum spacing of
1.5 km is required here. Parallel runways can provide about 70 operations per
hour. When wind in a particular direction does not provide the required
coverage, intersecting runways are preferred. The simultaneous use of both the
runways depends on the cross wind component on each runway. The intersection
point is to be fixed at the runway ends to achieve maximum capacity. Capacity
of non-intersecting runways depends upon the wind conditions and visibility.