Page 214 - Planning and Design of Airports

Geometric Design of the Airfield 179

FIGURE 6-2 Example of parallel runway confi guration: Orlando International Airport.

as noted earlier, the centerline separation of parallel runways deter-
mines the degree of interdependence between operations on each of
the parallel runways. It should be recognized that in future the spac-
ing requirements for simultaneous operations on parallel runways
may be reduced. If this occurs, new spacing can be applied to the
same classifications. Figure 6-2 illustrates an airport with multiple
parallel runways with various spacing.
If the terminal buildings are placed between parallel runways,
runways are always spaced far enough apart to allow room for the
buildings, the adjoining apron, and the appropriate taxiways. When
there are four parallel runways, each pair is spaced close, but the
pairs are spaced far apart to provide space for terminal buildings.
In VFR conditions, close parallel runways allow simultaneous
arrivals and departures, that is, arrivals may occur on one runway
while departures are occurring on the other runway. Aircraft operat-
ing on the runways must have wingspans less than 171 ft (airplane
design groups I through IV, see Table 6-2) for centerline spacing at the
minimum of 700 ft [5]. If larger wingspan aircraft are operating on
these runways (airplane design groups V and VI), the centerline spac-
ing must be at least 1200 ft for such simultaneous operations [5]. In
either case, wake vortex avoidance procedures must be used for simul-
taneous operations on closely spaced parallel runways. Furthermore,
simultaneous arrivals to both runways or simultaneous departures