Scientific Investigation & Reconstruction of Downburst-Related Aircraft Accidents

Downburst has been identified as one of the most important causes of aviation accidents during takeoff and landing. Aircraft performance degradation in this phenomenon gives pilot a very little opportunity to control the aircraft correctly. In this paper flight data analysis and simulation has been presented when the aircraft was traversing through the downburst. In the first step، wind components and their gradients were determined using FDR outputs. Then aircraft performance degradation was computed quantitatively with a factor called F-Factor. In both accidents were investigated in this research، F-Factor had values eventually resulted in accidents. Finally with modeling equations of motion and aerodynamic parameters، while using derived wind components، it was tried to find a suitable landing abort strategy. The results showed that best landing abort strategy during downburst encounter was to hold constant pitch attitude while using maximum engine thrust. Authors’ theory was exactly used on received data from NTSB and final results، in comparison with previous researches، completely verified the presented method. So، the required ability has been obtained for analysis of FDR data.