Study of Electromagnetic Emissions Due to Surface Discharges

Charge accumulation on aircraft skin in flight can lead to corona discharges, surface streamers and arcing. As these discharges take place, they provoke electromagnetic emissions that may cause functional disturbances of aircraft communication and navigation systems. The context of the study was an optimization of the design rules concerning stickers, paint layers and thickness. During that study, streamer discharges were generated on the surface of several metallic plates coated with various paint schemes and thicknesses in order to define some parameters of the dielectric coating in the accumulation and evacuation of charges. In this context, the emissions of surface streamers in the frequency bands of HF and VHF communication systems were assessed. The analysis showed that the electromagnetic emissions due to streamers are visible in HF band, and as expected, very little or no emissions were measured in VHF band [1]. As a complement, a functional test was performed with three A350-XWB VHF radio receivers coming from different suppliers and connected to an actual aircraft antenna. No disturbance was noted during the generation of streamer discharges. For HF, due to the size of the operational system, a complementary functional test is planned directly on aircraft.