WIND COVERAGE STUDIES
Basic Considerations. Establish tentative runway orientations by a
wind coverage study. Adjust tentative orientation for maximum construction
economy and for ease of future expansion, but comply with operation runway
Meteorological Conditions. Determine average weather conditions for at
least the last 5 years. Ascertain frequency of occurrence, singly and in
combination, for: wind (direction and velocity), temperature, humidity,
barometric pressure, clouds (type and amount), visibility (ceiling),
precipitation (type and amount), thunderstorms, and any other unusual weather
conditions peculiar to the area.
a) Usable Data. Use only data which give representative average
values. For example, do not consider extremes of wind velocity during
infrequent thunderstorms of short duration.
b) Source of Data.
Obtain meteorological data from one or more of the
National Weather Service
Bureau of Reclamation
U.S. Forest Service
Soil Conservation Service
Federal Aviation Administration
U.S. Army Corps of Engineers
Navy Oceanographic Office
U.S. Geological Survey
Wind Velocity and Direction. The following are the most important
meteorological factors determining runway orientation:
a) Composite Wind Rose. When weather recording stations are located
near a proposed site and intervening terrain is level or slightly rolling,
prepare a composite wind rose from data of surrounding stations.
b) Terrain. If intervening terrain is mountainous or contains lakes
or large rivers, allow for their effects on wind velocities and directions by
judgment, after study of topographical information and available meteorological
c) Additional Weather Data. Consider wind directions and velocities
in conjunction with visibility, precipitation, and other pertinent weather