Electromagnetic Emissions from an Electro-Impulse Deicing System in a CompositeWing Equipped with Lightning Protection

摘要

Electromagnetic interference (EMI) accompanying the use of the Electro-ImpulseDeicing (EIDI) system was investigated in 1988 and 1989. Results indicated that EIDI emissions inside aluminum wings were almost totally shielded, but EIDI inside composite wings produced emissions exceeding permissible levels unless shielding and grounding was provided for all components. However, lightning protection for composite wings require a fine mesh copper screen grid to be embedded in the composite. The questions arose concerning the shielding effect of this screen, to see if it would significantly reduce EMI from EIDI. Emissions tests were conducted on two similar composite wing leading edges with EIDI installed; one had a lightning protection grid. The results were negative; the embedded lightning protection wire added negligible shielding at all frequencies to the composite leading edge.