The advent of electronic digital technology has enabled unprecedented evolution of automation and expansion of aircraft functionality; however, this capability does not come free. Lightning is an intense form of the same type of electrical energy used by electrical/electronic equipment to process and transfer information. And systems incorporating such equipment are used more and more to implement aircraft functions, including Level A systems that affect safe flight and landing of aircraft. Because lightning is a common threat to Level A electrical/electronic (“fault-tolerant” or not) systems, lightning can translate into a threat to the aircraft itself. A strategy to achieve an acceptable margin of electrical/electronic system immunity to the indirect effects of lightning could include both traditional protection measures and system architecture measures.