Act as an aerospace systems lead. Draft a concept of operations (CONOPS) for a 4–6 seat eVTOL. Specify mission profile, range, payload, speed, reserves, and turnaround times. Produce a trade study comparing 3 architectures (tilt-rotor, lift+cruise, multicopter) across efficiency, safety, noise, certification risk (Part 23/OSA). Output a ranked recommendation with risks and mitigations.