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Calculate wind shear conditions

**Library:**Aerospace Blockset / Environment / Wind

The Wind Shear Model block adds wind shear to the aerospace model. This implementation is based on the mathematical representation in the Military Specification MIL-F-8785C [1].

The magnitude of the wind shear is given by the following equation for the mean wind profile as a function of altitude and the measured wind speed at 20 feet (6 m) above the ground.

$${u}_{w}={W}_{20}\frac{\mathrm{ln}\left(\frac{h}{{z}_{0}}\right)}{\mathrm{ln}\left(\frac{20}{{z}_{0}}\right)},\text{}3fth1000ft$$

where *u _{w}* is the mean wind speed,

The resultant mean wind speed in the flat Earth axis frame is changed to body-fixed axis coordinates by multiplying by the direction cosine matrix (DCM) input to the block. The block output is the mean wind speed in the body-fixed axis.

[1] U.S. Military Specification MIL-F-8785C, November 5, 1980.

Discrete Wind Gust Model | Dryden Wind Turbulence Model (Continuous) | Dryden Wind Turbulence Model (Discrete) | Von Karman Wind Turbulence Model (Continuous)