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During World War II, Landing Craft Utility (LCU) operated as commissioned Landing Craft Tank (LCT) under Flotilla Commanders. The LCT had an Ensign or Lieutenant Junior Grade as Commanding Officer, and operated independently or were transported aboard larger ships. At the end of the war, most of the several hundred LCU in service were decommissioned and mothballed, and a "Centralized Flotilla Command" was established at Naval Amphibious Base. This command became LCU Squadron ONE and was made up of the approximately thirty remaining LCU in the Pacific organized into three LCU divisions.

In July, 1947, a new command came into being next door to LCU Squadron ONE: Boat Unit ONE, a small craft command specializing in the Landing Craft Mechanized (LCM), and Landing Craft Vehicle/Personnel (LCVP). In 1950 in response to the outbreak of hostilities in Korea, both commands deployed craft to the Far East. Within a few months, more than 36 LCU and more than 120 LCM and LCVP were in Korea, manned by over 1.500 Sailors. These craft formed the spearhead of the amphibious assault at Inchon, and LCU Squadron ONE and Boat Unit ONE craft took part in every amphibious operation of the conflict. Following hostilitiles, a detachment of LCU Squadron ONE and Boat Unit ONE craft were permanently forward-deployed in Japan.

ACU 1 logoFollowing the conflict in Korea, LCU Squadron ONE and Boat Unit ONE craft took part in various operations around the Pacific including goodwill tours to Borneo, Singapore, Pakistan, Ceylon, Bombay and Karachi, evacuation of over 100,000 French military and Vietnamese refugees from North Vietnam, as well as providing lift for the armed withdrawal of Chinese Nationalist troops from the Tachen Islands to Taiwan. On December 5, 1958 the CNO reclassified LCU from commissioned vessels, with ENS or LTJG Commanding Officers, to combatant craft with Chief Petty Officer Craftmasters.

On October 1 1963, CNO directed a merger between Boat Unit ONE and LCU Squadron ONE in order to combine and streamline the operation of the two similar commands. Boat Unit ONE was disestablished and all boats and personnel were transferred to the three LCU Divisions. LCU Squadron ONE was renamed Assault Craft Squadron ONE (ACS-1), and the divisions changed from LCU Divisions to Assault Craft Divisions. The Squadron Commander was classified as a Commodore, with each Division having its own Commanding Officer and organizational staff. The squadron still retained its Western Pacific Detachment.

Beginning in 1963, ACS-1 craft were deployed to South Vietnam. Based at Naval Support Activity Danang, ACS-1 craft resupplied Marine forces far up river, and conducted day and night armed reconnaissance patrols. Over 20 ACS-1 Sailors were lost to hostile fire during this conflict, including the entire crew of LCU-1500. ACS-1 craft maintained a constant presence through the end of the conflict.

On 1 May 1968, CNO directed that Assault Craft Squadron ONE and its Assault Craft Divisions ELEVEN, TWELVE and THIRTEEN be disestablished, and reformed as Assault Craft Unit ONE (ACU 1). The overseas division became ACU-1 WESTPAC Detachment. The Squadron Commodore became the Commanding Officer.

On 2 August 1990, Iraqi forces invaded Kuwait and ACU-1 was one of the first Navy units to respond. Twenty LCM crews were immediately mobilized and flown to Al Jabail, Saudi Arabia, to begin offload of the Maritime Prepositioning Squadron ships. Meanwhile, on December 2, 1990 ACU-1 deployed nine LCUs and three LCMs as part of the Amphibious Task Force ONE. Within one month of arrival these craft offloaded over 20 million pounds of combat cargo.

Since September 11, 2001, ACU-1's mission set has expanded beyond the traditional assault and follow-on echelon operations to support the Global War on Terrorism. These missions include independent multi-day anti-piracy patrols, visit-board-search and seizure operations, oil platform defense, humanitarian assistance and disaster relief.



The Administrative Department manages the functions of the Command to ensure proper administrative support is provided to the command to accomplish its mission.


- Prepares and issues the Daily Plan of the Day
- Manages correspondence procedures and quality control to include proofreading correspondence received for signature of the CO and XO,prepares command muster report, and maintains command alpha roster, command calendar, schedules appointments for CO and XO.
- Manages Centralized Directives Program to include preparation, control, and maintenance.
- Manages Official Mail Program, receives, routes, and distributes incoming and outgoing official mail; maintains tickler on travel, awards, schools, evals and coordinates the command Planning Board for Training.
- Administers forms, reports, reprographic, and records management.
- Preparation of travel orders, both cost and no cost.
Command Career Counselor


Engineering Department under the leadership of the Engineer Officer is responsible for the repair and alteration on ACU ONE craft and equipment. The function of the department includes planning, scheduling, repair, and inspection of work to ensure its timely and satisfactory completion in accordance with prescribed method and standards. To perform its mission, the department is comprised of various shops to provide services and technical support to various crafts. This includes an Electrical & Facility shop, Safety shop, A/C & R shop, Calibration lab, Engraving shop, HT shop, Engine shop and a Damage Control Assistant. The department is also responsible in providing technical support and training to craft personnel. Engineering personnel conduct and evaluate results of Engineering Training Team (ETT) and Damage Control Training Team (DCTT) exercises, facilitating the engineering readiness of LCUs during Light –Off Assessment (LOA), all phases of CART and TSTA training. The Electrical and Facility shop is responsible for providing technical support and training to craft electrical personnel to accomplish their mission. The shop also maintains a centralized Tool Issue for electrical portable tools for the command. The shop reports, tracks and coordinates work within the command that PWC accomplishes. LCU operations in Sasebo, Japan

The HT shop welds, manufactures, and cuts all types of metal along with fabricating steel and aluminum items to enhance ACU One craft performance. The shop has also the capability to perform pipefitting, cutting, and all metal repairs required.

The DCA provides technical expertise and training of craft personnel in damage control including fire fighting, emergency repairs, and non- medical defensive measures against chemical, biological, and radiological weapons. They also evaluate and identify deficiencies in damage control actions and implement corrective actions.

The Engine shop provides technical assistance and repair of the crafts propulsion equipment, and auxiliary equipment. The shop also maintains a rotating pool to provide repair parts and logistic support to enable craft to accomplish their mission.

The A/C & R shop provides technical support and repair to the craft’s air condition and refrigeration systems and maintains on hand inventory of R-404, 134A, and R-22 refrigerant.

The Engraving shop fabricates nametags, placards, and various labels needed for the ACU One and tenant commands.

The Gauge Calibration Shop performs and maintains the calibration program for all crafts. The Safety shop is responsible for coordinating the implementation of a comprehensive safety program, ensures wide distribution of safety information, provides safety training to craft personnel, and provides the Commanding Officer with a periodic assessment of NAVOSH Program compliance.


The Medical Department is responsible for the safety and health of all hands assigned to ACU-1. Staffed by only one Independent Duty Corpsman and one general duty corpsman the department is responsible for a myriad of duties. In addition to routine sick call the medical staff also:

- Provide emergency care as necessary to the command - Review all health records to ensure accuracy and completeness
- Oversee all dental requirements
- Review and provide immunizations
- Monitor and implement the Hearing Conservation program
- Monitor and assist with potable water onboard the LCU’s
- Conduct Galley inspections of the LCU’s
- Provide basic first aid training to the command
- Provide advanced first aid training to the First Responders aboard the LCU’s
- Manage the Health protection programs for the command


The Operations department is the smallest department at ACU-1, consisting only of the Operations Officer, Training Officer, 2 Chiefs, 6 Petty Officers and 1 seamen. While small in size, the functions of the department are of vital importance in coordination of a wide range of assault craft commitments.

Current Operations: Responsible for the organization and employment of all assault craft per approved policies, directives, and plans. Responsible for preparing operational plans and orders derived from directives received from higher authority and for the supervision and execution of all assigned exercises and operational commitments.

Training: Responsibility includes matters of readiness and training for: tactical training strategy; inter deployment training cycle exercise planning; deck seamanship; inspections and assist visits; safety and PQS review.

Weapons: Responsible for the training and qualification of all ACU ONE personnel in Small Arms Weapons. Small Arms include M-16 Rifle, M-203 Grenade Launcher, M9 Pistol, M2HB .50 Cal MG, and M-60 MG. Maintain custody of over 800 weapons and related ammunition. Responsible for the inventory and issuance of all 782 gear in support of deployed forces.

Communications: Provides reliable, secure and rapid communications based on requirements adequate to meet the needs of ACU ONE in carrying out assigned mission. Ensures quality assurance of telecommunication facilities and communications security.

ADP: Responsible for the administration of the commands Classified and Unclassified Local Area Networks and peripheral computer equipment and management of over 100 computer workstations.

Reserve Liaison: Responsible for the administrative support for four reserve detachments (25 Officers/75 Enlisted) in Great Lakes, IL, Orange TX, Pt Hueneme, CA and Tampa FL.


S-1 Division provides logistic support for 14 Landing Craft, Utility (LCU), (10 based in San Diego, CA and 4 based in Sasebo, Japan) and 8 Landing Craft, Mechanized (LCM-8) based in San Diego, CA ; and the support of 4 Naval Reserve Detachments. ACU-1 is comprised of shore billet Storekeepers that manage the warehouse and logistical operations.

Created to be the integration between engineering and logistics, we perform a wide range of logistic support functions and work closely with our customers to identify and correct systemic problems and design procedural enhancements.

We combine in-service logistics, and acquisition capabilities with expertise from Repair Parts Petty Officer (RPPO) and feedback from Shore Engineering Department to increase the reliability and readiness of deployed Assault Crafts.

ACU-1’s Logistic Specialists include S-2 Division, also known as Culinary Specialists (CS’s) which provide stowage and food preparation to the crew while in homeport or while deployed. In addition, the CS’s execute command special meals, re-enlistment cakes and picnic luncheons.

The Hazmat Division is comprised of 3 BM’s who manage the transportation yard and the proper stowage of hazardous material.

Supply Department stands ready to provide Sailors with the highest level of courteous customer service. The department exceeds the expectations of all of its customers. Whether it's providing IMPAC card services, contracting, procuring, issuing, stowing and inventory of over 6,000 line items and uniforms, or managing hazardous material (HAZMAT).

 Landing Craft, Utility (LCU) Landing Craft Utility (LCU)

Length:  135 feet
Beam:  29 feet
Displacement:  375 tons (full load)
Speed:  11 kts
Range: 1200 nautical miles
Military Lift: 175 tons of cargo/3 tanks/400 combat-equipped troops                                                           
Crew:  11

 Landing Craft, Mechanized (LCM) Landing Craft Mechanized (LCM)

Length: 74 feet
Beam: 22 feet
Displacement: 130 tons (full load)
Military Lift: 60 tons of cargo/1 tank/100 combat-equipped troops
Crew: 4
Maritime Prepositioning Force Utility Landing Craft (MPFUB)
Maritime Prepositioning Force Utility Landing Craft (MPFUB)

Length: 41 feet
Beam: 14 feet
Displacement: 20 tons
Speed: 41 knots
Military Lift: 10 tons of cargo/30 combat-equipped troops
Crew: 4

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Commander, Assault Craft Unit (ACU) 1

3226 Tarawa Road
San Diego, CA 92155-5084

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