Wind Loading of Antennas

Calculation of the wind surface and the wind load of antennas

Often, it is best if the antenna is installed at the highest point in a given area. It is commonly known that the wind is at its highest there and therefore it is important to take wind loading into consideration. The figure shows the proportion between wind load F in Newton and wind surface Aw in m2. However, this can only be shown at a certain wind speed v. In the curve the wind speed is fixed at 150 kilometres per hour.		SEE ALSO:
		Useful Data main page SWR Nomograph (1+2) SWR including Feeder Loss Mismatch Loss related to SWR Attenuation vs. Frequency Field Strength vs. Radiated Power Field Strength in volt per Meter (V/m) vs. Radiated Power and Distance Conversion tables (1), (2) and (3)

Wind Loading	As shown in the table F=1111*Aw here a dynamic wind pressure q=0.64*v2=1111 is fixed. Remember to calculate speed in metres per second instead of kilometres per hour. Aw is determined by shape factor c and effective frontal area Ap. The shape factor is a table value, for instance the shape factor is c= 1.2 for a round whip antenna. The “effective frontal area” is determined by the antennas geometrical design, for instance a cylindrical antenna will have an area of height multiplied with diametre. The graph can be used if both wind load is known and a max. area is to be found or if the area of the antenna is known and the wind load on the antenna has to be found.