At what altitude do windshear warnings become active?

Windshear warnings typically become active at an altitude of 1500 feet. This is crucial for pilots as this altitude is commonly where aircraft begin their final approach, and they need to be especially vigilant during this phase. Windshear can significantly affect an aircraft's performance by causing abrupt changes in wind speed and direction, potentially leading to loss of control or an unexpected descent rate. Therefore, having windshear warnings activated at this altitude allows flight crews to be promptly informed about any dangerous conditions, enabling them to take appropriate measures to ensure the safety of the flight.

The activation threshold of 1500 feet is established based on operational data and safety protocols. It is understood that while windshear can occur at various altitudes, the most critical situations for approach and landing typically manifest at around this level, which is why it is selected for the activation of warnings.