Assessment of prevailing wind changes affecting aviation safety (case study: Tabriz airport)

The study of air accidents recorded 2007-2016 for all variety of present aircraft shows that 29.2% of all aviation accidents occurred due to unfavorable climate. between the climatic elements, wind conditions have the greatest impact on the safety of airplanes, especially during takeoff and landing. So that unfavorable wind conditions for flying, the main cause or at least a contributing factor in 47% of all aviation accidents related to climate. Also the contribution of various wind conditions in aviation accidents caused by this element are respectively: crosswind: 55%, tailwind: 22%, gusty wind(Sudden change in wind speed): 8%, wind shear(Sudden change in wind direction and speed): 8%, variable wind(Sudden change in wind direction): 5% and dust devil or whirl wind: 2%. generally, it can be said that various climatic elements have impact on aviation safety, and between these elements the greatest impact is the wind conditions and in particular the crosswind effects on aviation safety. As a result of changes in winds, it can be considered a hazard to the aircraft and it can increase the status of the aircraft in-flight loss of balance. As we know, runways are made in the prevailing wind direction of the area; as a result, a change in the prevailing wind direction of an airport can increase the amount of crosswind relative to the runway, thereby negatively affecting during takeoff and landing. Therefore, the impact of change on wind conditions and in particular on the direction or speed of prevailing winds are important and in this study the impact of their changes at the usability factor of the current runway of Tabriz airport, is discussed.