Probabilistic reasoning for intelligent wind shear avoidance

Avoiding severe wind shear challenges the ability of flight crews because it involves assessing risk from uncertain evidence. A computerized intelligent cockpit aid can increase flight crew awareness of wind shear, improving avoidance decisions. A primary task in the development of such a cockpit aid is providing a means of assessing risk from evidence of wind shear from sources with varying reliability. The Federal Aviation Administration’s Windshear Training Aid provides guidelines for assessing the risk of wind shear encounter from meteorological evidence. Use of these guidelines in the cockpit is complicated by uncertainty surrounding meteorological knowledge of wind shear. Bayesian network representation is discussed as a means of modeling this uncertain knowledge in a computer. A probabilistic model of the Windshear Training Aid guidelines using Bayesian network representation is presented. This model combines evidence from sources of varying reliability and incorporates results from meteorological studies of wind shear. The probabilistic model can provide flight crews with meaningful estimates of risk to aid their decisions, using evidence from a variety of sources and a base of meteorological knowledge.