Pilot here. That aircraft wasn’t built with an electrical system, and people only install them when they need to fly into populated areas— it’s basically an antique. No way to radio anybody, barely any checklists to follow; generally extraordinary simple— just throttle and magnetos, if it’s anything like the Piper Cub… so engine failure is usually due to fuel exhaustion, the more likely case because also there wasn’t a fire near the landing site despite the crumpled metal, or oil leak, unlikely because the prop freewheeled once the plane sped up, or maybe sure the magnetos were turned off. More generally, there’s something off about the person… his emotional connection to his experience does not seem typically expressed.