In which phase of flight does wind shear have the greatest effect on aircraft?

Wind shear has the greatest effect on aircraft during the approach or departure phase for several reasons. This is the critical period when the aircraft is transitioning from high-speed cruise to slower speeds and lower altitudes, where it is more susceptible to changes in wind direction and speed.

During approach and departure, the aircraft is operating at lower altitudes and slower speeds, making it less stable and more vulnerable to abrupt changes in wind velocity. Wind shear can lead to sudden loss of lift or increased drag, which can significantly affect the aircraft's performance and handling characteristics. Pilots must maintain careful control of the aircraft's attitude and speed during these phases, as the consequences of wind shear can be more severe when compared to other flight phases.

Furthermore, takeoff and landing involve similar conditions as approach, as they also occur at low speeds and altitudes. However, wind shear is particularly problematic during approach because that phase involves descending towards the runway, making any sudden changes in wind direction or speed particularly critical to managing the aircraft's descent rate and maintaining a safe glide path. In cruise, the aircraft operates at high altitudes and speeds, where wind shear is less impactful due to the increased distance from the ground and the aircraft's better aerodynamic performance.