This document addresses the potential interference to installed aircraft electrical and electronic systems from Portable Electronic Devices (PEDs) carried aboard by passengers. It defines the potential interference phenomena; outlines the risk potential from interference events; provides test methods to determine whether or not a potential for interference exists for certain PEDs@ aircraft and combinations thereof; and addresses acceptable levels of interference. The report also recommends modification of Federal Aviation Regulation 91.21@ continued PEDs testing to identify and better define the possibility of interference to aircraft electronic systems@ increased public awareness of the potential for interference from PEDs@ and the development and use of devices to detect spurious PEDs emissions.