Assault Amphibious Vehicle (AAV7)

Origins and development

The Marine Corps began looking for a replacement for its LVTP-5 amphibian tractor in 1964, citing its short range, slow water speed and heavy maintenance needs ^[1]. FMC Corporation won the development contract in February 1966 and delivered 12 prototypes in the summer of 1967 ^[1]. After tests at sites including Aberdeen, Yuma, Fort Greely in Alaska and Panama, the Corps ordered production in 1970; first deliveries came in August 1971, and the Landing Vehicle, Tracked, Personnel-7 (LVTP-7) entered service in March 1972 ^[1][3]. It was smaller and lighter than the LVTP-5 but faster on land and in water, swam with water jets instead of its tracks, and had a stern ramp for quicker loading and unloading ^[3][4].

FMC built about 1,100 vehicles of the first LVT7 family, in personnel, command and recovery versions, between 1971 and 1974 ^[1]. A service life extension program from 1982 added a new Cummins engine, a new transmission and other changes, 333 new vehicles were built from 1983 to 1985, and in 1984 the family was redesignated AAV7A1 ^[1][2]. Later upgrades added a turret with a .50 caliber machine gun and a 40 mm grenade launcher, and add-on armor in the early 1990s that gave the vehicle its ribbed look ^[1][4]. From the late 1990s the RAM/RS program fitted a 525 hp engine and suspension parts shared with the Army's Bradley Fighting Vehicle ^[1][4]. A survivability upgrade started in 2015 was canceled in 2018 after the Corps chose a new vehicle ^[1][4].

Combat service

The LVTP-7 arrived too late for the Vietnam War ^[4]. Argentina used its LVTP-7s in the opening phase of the 1982 Falklands War, and US Marines used theirs in Lebanon in the early 1980s, in the Grenada landing of October 1983, in the 1991 Gulf War and in Somalia ^[1][4]. In Iraq in 2003, eight AAVs were disabled or destroyed in fighting at Nasiriyah, which drew criticism of the protection the vehicle gave its crews ^[1][4]. In August 2005 a roadside bomb struck an AAV near Haditha, killing 14 Marines and an Iraqi interpreter ^[1].

Design and how it works

The AAV7A1 is a tracked armored vehicle with an aluminum hull, about 26 ft (7.94 m) long and weighing about 29 t (64,000 lb) ^[1]. It has a crew of three and carries up to 21 troops, who enter and leave through a large rear ramp ^[1][3]. On roads it can reach about 45 mph (72 km/h) ^[1][2]. In water two water-jet pumps, each rated at 14,000 US gallons (53,000 liters) per minute, drive it at about 7 knots (8 mph, 13 km/h), and BAE Systems says it can get through plunging surf 10 ft (3 m) high ^[1][2]. The family includes the AAVP7A1 personnel carrier, the AAVC7A1 command vehicle and the AAVR7A1 recovery vehicle ^[2].

The 2020 sinking off San Clemente Island

On 30 July 2020, during predeployment training, an AAV sank off San Clemente Island, California, as it returned to the amphibious ship USS Somerset after an exercise ashore ^[5][6][8]. It carried 16 people: three crew, 12 Marines and a Navy corpsman ^[5]. Eight Marines and the corpsman died, the deadliest AAV training accident in Marine Corps history; seven people survived ^[5][7]. The vehicle came to rest about 385 ft (117 m) down ^[5].

The Marine Corps command investigation, released in March 2021, found that a combination of human and mechanical failures caused the sinking and delayed the rescue ^[5][6]. The vehicle leaked at several points, and its bilge pumps could not keep up after its transmission failed ^[5][6]. Its distress flag went unseen for more than 20 minutes, and no safety boats were in the water ^[5][6]. The troops aboard were not told to shed their gear or prepare to leave, and investigators cited inadequate training, poor maintenance and poor judgment by leaders ^[5]. By the time a second AAV arrived, the vehicle had been taking on water for about 45 minutes; the two collided, the damaged AAV turned broadside to the swell, a wave came in through an open hatch, and it sank quickly with 11 people still inside ^[6]. The commander of Marine Corps Forces, Pacific, Lt. Gen. Steven Rudder, wrote that the mishap "was preventable" ^[5].

AAV water operations were suspended while equipment, procedures and training were reviewed, and every vehicle was inspected under new criteria; most of the fleet failed the stricter checks ^[5][6][7]. Two commanders were relieved in October 2020, the commander of the 15th Marine Expeditionary Unit was relieved in March 2021, and seven other people faced administrative or disciplinary action ^[5][6]. Five officers were censured in June 2022 ^[8]. In December 2021 the Marine Corps announced that AAVs would no longer go on routine deployments or train in the water, and would return to the water only for crisis response ^[7].

Retirement and legacy

From 2018 the Marine Corps began replacing the AAV with the wheeled Amphibious Combat Vehicle, after earlier planned successors, including the Expeditionary Fighting Vehicle canceled in 2011, did not reach service ^[1][4]. AAVs kept working on land, including at Exercise Bright Star in Egypt in September 2025 ^[4]. The Corps held a sundown ceremony at the Assault Amphibian School at Camp Pendleton, California, on 26 September 2025, marking 53 years of service ^[3][4]. BAE Systems still offered the vehicle for export, and about a dozen other countries, among them Japan, South Korea, Taiwan, Brazil and Spain, operate it ^[1][2][4].

Related entries

• Landing Vehicle Tracked (LVT, amtrac)Military amphibians · 1935 (Alligator); 1941 to 1945 (wartime LVTs)
• Amphibious Combat Vehicle (ACV)Military amphibians · 2018 to present
• LARC-VMilitary amphibians · 1963 to present
• How amphibious vehicles workHow it works ·