I didn't know these existed. Some are a bit crude but then so are most homemade subs all over the world. The future looks good for midget and naval drones
This is a private project. The Vietnamese MoD have another secret midget submarine project called "TN 75" (Submarine-75 ton). They aimed at designing bigger midget sub to replace the old North Korean one that is still in service of the Vietnamese navy.
In late 18th century, one of the many small Princes of HRE had good Relations to Portugal, for this reason he did experiments with submarines in large german lake Steinhuder Meer. For the small size of his state, his 1400 men Army was rather large, also build one or two miniature fortresses, very small, but build after most modern principles.
Ship building project TN 75 is a military project. it, is 75 tons Midget submarine, has happened reported by Vietnam People's Navy Newpaper. Also, its image has already been leaked online. Link to the new paper: baohaiquanvietnam.vn/print/vien-ky-thuat-hai-quan-23-luot-tap-the-va-ca-nhan-duoc-khen-thuong Another is project is the Dolphin class USV and the underwater target drone unveiled during military convention
In late 18th century, one of the many small Princes of HRE had good Relations to Portugal, for this reason he did experiments with submarines in large german lake Steinhuder Meer. For the small size of his state, his 1400 men Army was rather large, also build one or two miniature fortresses, very small, but build after most modern principles.