Wind Shear & Microburst
Wind Shear
A sudden change in wind speed and/or direction over a short distance. Can be vertical or horizontal.
- Effect: Sudden gain or loss of airspeed and lift.
- Sources: Thunderstorms, Frontal systems, Jet stream, Topography.
Microburst
A small scale intense downdraft that descends to the ground and spreads out (outflow).
- Size: From 1 to 4 km diameter.
- Duration: Short lived (5-15 mins).
- Vertical Speed: Up to 6,000 fpm downdraft.
- Encounter: Headwind increase (Performance gain) -> Downdraft (Sinking) -> Tailwind increase (Performance loss/Crash).
Recovery Procedure
If Windshear Warning is triggered or encountered:
- Thrust: TO/GA (Take-off/Go-around) - Maximum Thrust.
- Pitch: Rotate towards 15° or stick shaker activation. Follow Flight Director if Guidance provided.
- Configuration: DO NOT CHANGE gear or flap configuration (drag/lift changes can be fatal during recovery).
- Level off: Only after clear of shear and positive climb established.