TV-Series
Description
David Young serves as the operations manager and mechanic for the Sirius Platoon, a special unit within the Space Defense Force (SDF). He is stationed aboard the platoon's distinguished locomotive, the Big One, and his responsibilities include maintaining the vehicle's systems while also participating directly in missions.

In terms of personality, David is characterized as an easy-going and cheerful individual who acts as the mood maker for his team. This lighthearted and sociable nature is presented as a direct contrast to another member of the Sirius Platoon, Bruce J. Speed, who is more hot-headed and serious. David is friendly with Bruce, embodying a relaxed counterpart to Bruce's intensity. This approachable and upbeat demeanor allows him to adjust the atmosphere within the group, making him a central figure for maintaining team morale.

Within the narrative, David holds a significant and supportive role relative to the protagonist, Manabu Yuuki. He is described as being a figure akin to an older brother to Manabu, providing guidance and a sense of familial connection. His role is not solely defined by technical support or camaraderie; he also demonstrates exceptional skill under pressure. David possesses superbly refined piloting abilities, particularly showcased during critical moments when he must manually control the Big One. His competence becomes vital during dangerous maneuvers, such as evading incoming missiles or navigating the massive locomotive out of an asteroid field.

Physically, David is an adult male with green eyes and shoulder-length gray hair. He is consistently depicted in his SDF uniform, which includes gloves and a belt. While his primary duties involve operations management and mechanics, his most notable ability is his elite-level train operation, proving himself to be one of the most capable pilots in his unit when automation is insufficient. No information is available regarding specific character development arcs or detailed personal motivations beyond his established role as a supportive and skilled member of the Sirius Platoon.