Wind shear, also known as windshear, refers to a difference in wind speed and/or direction over a relatively short distance in the atmosphere. This phenomenon can occur either vertically (with changes in altitude) or horizontally (with changes in lateral position at a given altitude).
Let’s break it down further:
Vertical Wind Shear (Microburst):
Vertical wind shear involves changes in wind speed or direction as you ascend or descend through the atmosphere.
It affects aircraft during takeoff and landing. Pilots must be cautious, especially when encountering microbursts (sudden downward wind gusts) that can significantly alter airspeed.
In severe cases, vertical wind shear can lead to dangerous conditions for aviation.
Horizontal Wind Shear:
This type of wind shear occurs when wind speed changes laterally (horizontally) at a specific altitude.
It can be associated with jet streams, fronts, and other weather features.
For pilots, horizontal wind shear poses challenges during approach and departure.
Effects of Wind Shear:
Aircraft Control: Wind shear affects an aircraft’s stability and control. Sudden changes in airspeed or direction can be hazardous.
Sound Propagation: Wind shear can bend sound waves, causing sounds to be heard where they normally wouldn’t.
Tropical Cyclones: Strong vertical wind shear inhibits tropical cyclone development but helps organize thunderstorms into longer life cycles.
Jet Stream: The jet stream exists due to differences in wind speed at different altitudes, a concept explained by the thermal wind effect.
Safety: Wind shear has been a contributing cause of several aircraft accidents.
Noticeable Incidents:
Delta Flight 191 Dallas Fort Worth
NTSB Accident Report for Delta 191
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