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The extent to which wind shear presents a hazard to aircraft has been well documented in the last ten years. Since some wind shear can occur in otherwise relatively good weather, the most hazardous kind, a microburst, is associated with rain showers and thunderst ....

Middle of Essay
.... wind shears. However, there are two types of down drafts that are particularly hazardous to flight operations because of there severity and small size. Professor T. Fulita, an atmospheric scientist from the University of Chicago, coined the term downburst for a concentrated, sever downdraft that induces an outward burst of damaging winds at the ground. He also introduced the term microburst for a downburst with horizontal dimensions of 4km or less (Lester 11-4). Microbursts form by the same process that produce the more common and less intense down drafts; that is, by precipitation drag and cooling due to the evaporation and melting of precipitation ....