Evaluation of a technique to quantify microburst windshear hazard potential to aircraft

A wind shear hazard index, known as the F-factor, is investigated for application with look-ahead sensors. Based on data from microburst simulations with the NASA windshear model, the downdraft results in a significant contribution to the wind shear hazard, especially at altitudes above 150 meters. Since most look-ahead wind shear sensors can detect only horizontal shear and cannot measure vertical velocity, a relationship is developed for approximating the total F-factor using information based solely on the horizontal wind shear and altitude. This relationship is then tested using data from several microburst cases.>