Aeronautical communications still heavily depend on analog radio systems, despite the fact that digital communication has been introduced to aviation in the 1990’s. Since then, the digitization of civil aviation has been continued, as considerable pressure to rationalize the aeronautical spectrum has built up. In any modern digital communications system, the threat of digital attacks needs to be considered carefully. This is especially true for safety-critical infrastructure, which aviation’s operational communication services clearly are. In this article, we reverse the traditional approach in the aeronautical industry of looking at a system from the safety perspective and assume a security-oriented point of view. We use the lens of security properties to review the requirements and specifications of aeronautical communications infrastructure as of 2021 and observe that most standards lack cybersecurity as a key requirement. Furthermore, we review the academic literature to identify possible solutions for the lack of cybersecurity measures in aeronautical communications system. We observe that most systems have been thoroughly analyzed within the academic security community, some for decades even, with many papers proposing concrete solutions to missing cybersecurity features. We conclude that there is a systematic problem in the design process of aeronautical communication systems. We provide a list of eight key findings and recommendations to improve the process of specifying such systems in a secure manner.