Almost all major components have undergone the modernization – propeller and steering systems, navigational and hydroacoustic equipment.
The modernized midget sub “Triton-1M” is still intended for two crew members and has a cruising capacity of six hours, speed of up to six knots. Its submersion depth is about 40 meters.
The modernized Triton looks smoother and can move at higher speed at decreased power consumption.
Every diver had his own individual weapons that were packed into special sacks, those sacks were sealed ashore and put under the seats in a sub. They took the sacks with them each time they left “Triton”.
Midget sub surfacing was executed by means of high-pressure air stored in special solid cylinders. That system was nonvolatile: it was enough to open a valve and fill a tank with air.
And these are 80 Japanese midget subs of D type – “Koryu”, October 19th, 1945.