Manned vehicles is a concept defining transportation or operational systems explicitly designed to accommodate and be directly controlled by a human operator present onboard. As an academic concept and research domain, it investigates the complex interplay between human capabilities and system design, focusing on human factors engineering, crew interface design, life support systems (where environments require), safety protocols, and the performance implications of human interaction. This field is significant for enabling human exploration, transportation, and complex tasks in diverse environments by optimizing human-machine integration and addressing the unique challenges and opportunities presented by direct human involvement in system operation.