Where do static discharges primarily occur on an aircraft?

Static discharges predominantly occur on primary surfaces of an aircraft due to their exposure to airflow and environmental factors during flight. These surfaces include the wings and the fuselage, which are crucial for the aerodynamic performance of the aircraft. As the aircraft moves through the atmosphere, air friction can cause the build-up of static electricity on these surfaces. When the static charge reaches a certain level, it can discharge, leading to phenomena like the visible blue glow often seen in some weather conditions.

This is particularly significant because primary surfaces are also critical areas for ensuring the stability and control of the aircraft. Effective management of static discharge in these areas helps prevent interference with avionics systems and ensures that electrical charge does not affect navigational and communication equipment, which could compromise aircraft safety.

In contrast, while landing gears, tails, and leading edges may experience some static discharge due to their functionalities and exposure to airflow, they do not typically serve as the primary sites for static electricity build-up compared to the primary surfaces.