A 60-year-old farmer from China’s Anhui province has captured attention nationwide after successfully building and launching his own homemade submarine, nicknamed the “Big Black Fish.” Zhang Shengwu, a former carpenter with experience in shipping, crafted the seven-metre steel sub from scratch near his rural village. His creation weighs five tons, fits two people, can dive up to eight metres, and stay submerged for 30 minutes.
Inspired by a submarine documentary he watched in 2014, Zhang said, “I’ve seen iron boats and wooden boats all my life, but never one that could dive. I figured—if others can do it, why can’t I?” Despite his wife’s protests calling the project “expensive, risky, and useless,” Zhang pressed on, investing 5,000 yuan in materials to start with. His first prototype launched in 2016 but leaked. Undeterred, he spent another 40,000 yuan to build a sturdier model, adding concrete ballast and two ballast tanks to improve submersion.
Recent footage from state broadcaster CCTV shows Zhang confidently piloting the “Big Black Fish” during its river trial, both surfaced and submerged. While it doesn’t rival the Chinese navy’s nuclear submarines, Zhang’s electric-powered sub travels at four knots and must resurface every 30 minutes. Now, with one dream already beneath the surface, Zhang has his sights set on building an even bigger submarine next.
