oY ) enemy vessels (especially submarines, which are the _ largest vessels capable of approaching undetected by surface surveillance) from entering a protected area and, at the same time, to permit the safe passage of friendly shipping. This mission may be accomplished by— (1) Forcing the enemy, through the psychological effect of an unseen threat, to be cautious and uncertain when planning operations in water areas which they know or believe to be mined. (2) Effecting the destruction of or causing serious damage to hostile vessels entering the mine field. (3) Preventing enemy vessels from entering the harbor during periods of darkness and low visibility, or when other weapons of the Army and Navy are entirely or partially ineffective. _ (4) Restricting maneuver of enemy vessels in formation.
DesignationFM 4-7
EditionApr 1945
StatusSuperseded
Pages102
FunctionEngineering
CollectionHistoric
Public domain (U.S. Government work)