Publications

Aviation weather refers to any type of weather that can affect the operation of an aircraft – anything from a brief delay in departure to a catastrophic accident during flight. Wind shear and events associated with convective weather were recognized as an aviation hazard long before Dr. Theodore Fujita began publishing his now-famous treatises. On July 28, 1943, American Airlines Flight 63 from Cleveland, Ohio, USA to Nashville, Tennessee crashed after the pilot lost control of the Douglas DC3. The pilots and numerous passengers were fatally injured. The aircraft was destroyed by impact and post crash fire. The weather report at the time included warnings for storms, heavy rain, lightning and severe turbulence. The Civil Aeronautics Board found that the probable cause was a loss of control of the aircraft due to unusually severe turbulence and violent downdraft caused by a thunderstorm. In the ten-year period from 1987 through 1996, 24% of all U.S. accidents were judged to be "weather related". For the twenty-year period 1976 to 1996 fully 43% of U.S. accidents were judged to have involved wind or wind shear, and 2.3 % thunderstorm, although the two data elements are not mutually exclusive. In the U.S., approximately 82% of accidents are general aviation; the rest are air carriers and commuters of various types. When general aviation accidents are negated, and only air carriers are considered, wind and wind shear issues account for 9.5% of accidents. The Weather Systems Processor (WSP) has been developed to reduce the impact of severe weather conditions on air traffic by providing information concerning weather conditions in the airport terminal environment. WSP provides warnings to air traffic controllers and supervisors of hazardous wind shear and microburst events in the terminal area, forecasts the arrival of gust fronts, and tracks thunderstorms, providing a complete picture of current and future terminal area hazardous weather conditions that may impact runway and airport usage. Common weather situation awareness allows Terminal Approach, Tower Controllers and other traffic management personnel to jointly plan with confidence and safely manage more arrivals and departures with less delay. Knowledge of the location, severity and movement of hazardous weather allows dynamic adjustments to be made in routing aircraft to runways, approach and departure corridors, terminal arrival and departure transition areas (i.e. gate-posts) and other air routes.