This paper discusses the merits, benefits and usage of autonomous key management (with implicit authentication) (AKM) solutions for securing Electronic Module to Electronic Module (i.e. ECUs, FCC, REUs, etc.) communication within air (and defense) vehicles and IoT applications; particularly for transmissions between externally exposed, edge Electronic Module sensors connected to Electronic Modules within the air (and defense) vehicle infrastructure. Specific benefits addressed include reductions of communication latency, implementation complexity, processing power and energy consumption. Implementation issues discussed include provisioning, key rotation, synchronization, re-synchronization, digital signatures and enabling high entropy.