Mariner has a dark blue exterior on the lower half of the hull, and Ranger has a gray hull.
The U.S. Pacific Fleet, headquartered in Hawaii, began its second multi-domain unmanned capabilities exercise May 1, 2023. The Fleet’s exercise, called Unmanned Systems Integrated Battle Problem (UxS IBP) 23.1, is a tactical warfighting rehearsal event conducted by U.S. 3rd Fleet headquartered in San Diego, California to test and develop fleet-centric concepts and capabilities, according to the U.S. Navy.
In mid-August, four U.S. Navy unmanned surface fleets, Mariner, Ranger, Sea Hunter, and Seahawk, were seen heading to Pearl Harbor in Hawaii.
The U.S. Navy’s USVs are part of Ghost Fleet Overlord, a prototyping program launched in 2018 to integrate multi-mission unmanned vessels into the fleet. Its sister ships, Ranger and Mariner, were also commissioned by the U.S. Navy as part of a Department of Defense project to bring autonomous navigation technology to maritime vessels.
The two vessels were developed in collaboration between the US defense technology company Leidos and the US shipyard Gulf Craft.
Two sister vessels measure 193 feet (59 meters) long and 32 feet (10 meters) wide. It maintains cargo carrying capacity of two 20-foot containers and four 40-foot containers, but the containers are often equipped with additional systems and sensors essential to the vessel’s operation. It is equipped with Lockheed Martin’s Aegis combat system and can link with other Aegis ships in the fleet. So far, it has conducted test firings of the SM-6 interceptor missile.
According to a Baird Maritime report published on November 30, 2022, both Mariner and Ranger utilize a design that was originally developed for fast crew transfer and supply duties in support of clients in the offshore oil and gas industry. Modifications on each boat include the addition of satellite communications, three radars of different bands, electro-optical and infrared sensors, and radios.
Yokosuka, the home port of the U.S. Navy’s 7th Fleet, is bustling with activity on September 18. Besides Mariner and Ranger, the Independence-variant littoral combat ship (LCS) USS Oakland (LCS 24) also made a rate port call at Yokosuka.
These ships’ visit to Yokosuka may be aimed at showcasing American defense co-operation with Japan.
