The objectives of this work were to identify human performance risks and benefits of adaptive systems through a systematic analysis and heuristic evaluation of adaptive system component types and characteristics. As flight deck automated systems have more access to aircraft data, sensor data, stored databases, communicated information, and real time flight crew inputs, as well as more ability to process that information in sophisticated ways to identify situational priorities and context, it is becoming more realistic for those automated systems to adapt their behavior based on context. Automated systems that can make such changes on their own are called adaptive systems. The concern here is with adaptive systems that are perceived by the pilot to behave non-deterministically even though they are technically deterministic. Based on a framework to describe the types and characteristics of adaptive system components, a risk/benefit analysis was preformed to identify potential issues. Based on this analysis, eight representative adaptive system storyboards were developed as the basis of a heuristic evaluation with pilots to validate the analysis and explore more detailed issues and potential risk mitigations. The value of this work is expected to be in suggesting adaptive system issues, risks, and guidelines that need to be considered in making design decisions and approving new adaptive systems on the flight deck.