MILITARY/SPECIAL PURPOSE BOAT
The expansion of the small-boat Navy will augment the service by providing larger ships a way to patrol and police shallower waters and rivers inland. They also can feed information to the fleet and operate in littorals within reach of missiles that could threaten large vessels.
Special Purpose Vessels are often multi-role craft intended for a variety of specific jobs during war or peacetime. A rescue lifeboat is used to attend a vessel in distress, or its survivors, to rescue crew and passengers. A rescue lifeboat is designed with specialized features for searching for, rescuing and saving the lives of people in peril at sea or in estuaries.
The term 'motor lifeboat' is used to designate shore-based rescue lifeboats which are generally manned by full-time coast guard service personnel. On standby rather than on patrol mode these vessels are ready for service rather like a crew of fire fighters standing by for an alert.