Beachmasters are the interface between the Navy part of the amphibious operation and the Marine part.
From the Wiki:
Mission
Beachmaster Unit One deploys and supports combat ready Beach Party Teams in support of amphibious operations around the world. Their function is to control
landing craft,
lighterage, and
amphibious vehicles in the vicinity of the beach from surf line to high water mark, and coordinate movement over the beach of equipment, troops, and supplies. They also maintain observation of wind and surf conditions, and provide limited assistance in local security and beach defense. They have the capability to provide beach and surf zone salvage with use of their
LARC-V vehicle and provide the evacuation of casualties, prisoners-of-war, and non-combatants.
Beachmaster Unit 1 reports to
Naval Beach Group 1.
Beach Party Teams are responsible for controlling the boat traffic in the surf zone, controlling the beaching and retracting the landing craft, and directing the smooth and efficient flow of personnel and material over the beach. Beach Party Teams are led by the Beachmaster Team Commander. Beachmaster Unit One has 8 deployable departments.
And from the Wiki for Naval Beach Group 1:
Mission
Since its inception 19 July 1948, Naval Beach Group ONE (NBG-1) and its component commands have participated in a variety of
amphibious operations. From the early years of assaults during the
Korean and
Vietnam conflicts to the modern and technically sophisticated amphibious operations in
Somalia and
Iraq, the men and women of NBG-1 have served throughout the
Pacific and
Indian Oceans in support of US policy abroad.
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Commander, Naval Beach Group ONE (CNBG-1) functions under two distinct missions. During amphibious assaults, he provides personnel to support and operate causeway
lighterage,
LCACs,
LCUs, buoyant ship-to-shore bulk fuel systems, beach traffic control, and beach salvage equipment. The second mission is under the
Maritime Preposition Force (MPF) concept which uses the equipment and supplies prepositioned on board forward deployed
Maritime Prepositioning ships (MPS). Joining forces with the
Marine Expeditionary Brigade (MEB), CNBG-1 forms and commands the
Naval Support Element (NSE) and is airlifted into an objective area to establish camp support, conduct ship-to-shore movement, beach party operations and debarkation operations in support of the offload of each MPF ship.
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CNBG-1 is also responsible for conducting Amphibious Specialty Training (PHIBSPECTRA) for all
US Pacific Fleet amphibious ships. The PHIBSPECTRA Team provides in-depth training in well deck operations to prepare
Expeditionary Strike Group (ESG) ships for deployment to the Western Pacific and Indian Oceans.
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