Power Line Communication (PLC) systems are good candidates for next-generation aircraft communication channels. On-board power buses must meet stringent safety requirements that mandate the use of Transient Voltage suppressors (TVS) for lightning protection. These devices strongly degrade the performance of the communication channel. In this paper we analyze the impact of the lightning protection circuit used in aircraft power buses both theoretically and experimentally. It is shown that TVS devices are responsible for distortion and attenuation in the PLC signal band (1 MHz-100 MHz). We introduce a novel co-design strategy, matching PLC coupler to lightning protection conforming to air travel safety regulations. Our experimental results demonstrate that both constraints can be met using our proposed architecture.