Submarine designed to be unsinkable - has steel cuboid buoyancy bodies fitted on sides of hull of submarine ensuring buoyancy of submarine if all air is discharged

摘要

Steel cuboids are fitted on the sides of the hull of the submarine (1). They are designed to ensure the buoyancy of the submarine if all the air is discharged. The submarine surfaces when all of the ballast is released. This enables rescue to be effected in emergency situations.