Underwater apparatus

A naval mine configured to be released by a release assembly comprising:

• an impermeable casing;
• an explosive charge arranged inside said impermeable casing;
• a detonator, which can be operated to trigger said explosive charge;
• and
• a control device configured to operate said detonator;
• the naval mine being characterized in that it comprises:
• a fillable chamber (in particular, not filled with water and) provided with at least one opening;
• and
• a closing system to close or open said at least one opening;
• said closing system is configured to open said at least one opening so as to allow water to flow into the fillable chamber, when the naval mine is released by said release assembly;
• the fillable chamber being sized so as to ensure that the naval mine immersed in water assumes a neutral hydrostatic buoyancy when said closing system closes said at least one opening and said fillable chamber is not filled with water, and a negative hydrostatic buoyancy when said closing system opens said at least one opening and water flows into said fillable chamber so as to obtain a loaded chamber.