USV Maxlimer

Lore & Background

Maxlimer was constructed in Maldon, Essex, for the GEBCO-NF Alumni Team, an international group competing in the Ocean Discovery X Prize. During the competition in late 2018, Maxlimer deployed a HUGIN autonomous underwater vehicle to map 278 sqkm of seafloor in the Mediterranean Sea off the Greek city of Kalamata in 24 hours, making GEBCO-NF the winning team. In May 2019, Maxlimer made a demonstration crossing of the North Sea between West Mersea, England and Ostend, Belgium, carrying a cargo of 5 kg of oysters on the outbound trip and a case of beer on the return; SEA-KIT stated it was the first commercial autonomous crossing of the North Sea. In July 2019, Maxlimer deployed and recovered a HUGIN Unmanned Underwater Vehicle (UUV) several times in commercial service for Equinor to inspect offshore underwater pipelines in the North Sea, the first time inspection equipment had been remotely controlled past line of sight.

SEA-KIT intended to send Maxlimer on a transatlantic crossing in early 2020 as part of a project co-funded by the UK Space Agency through the European Space Agency’s Business Application programme, which would have been the first unmanned crossing of the Atlantic, but the voyage was cancelled due to restrictions imposed during the COVID-19 pandemic. Instead, in July 2020, Maxlimer sailed from Plymouth on a 22-day mission to map about 1000 sqkm of previously uncharted seafloor 460 km southwest of England on Europe's continental margin. The project aimed to demonstrate the capabilities of current technologies to survey unexplored or inadequately surveyed ocean frontiers and proved the capabilities of SEA-KIT's USV design, namely long endurance, over-the-horizon capability and ocean-going ability. The Atlantic mission was covered by BBC News.

The SEA-KIT X-class USV, of which Maxlimer was the first, is a remotely controlled, configurable mother-ship platform that can launch and recover remote vehicles such as large AUV/UUVs or ROVs for missions including deep-water bathymetry, offshore and subsea asset inspection and hydrographic survey. Data can be transmitted via broadband link or satellite following on-board processing and compression, or stored on board for future retrieval. SEA-KIT USVs are controlled using SEA-KIT's proprietary G-SAVI control and surveillance platform, which provides safe and secure operation from remote control centres.

Reader's Guide

USV Maxlimer's significance lies in its role as a proof-of-concept vessel demonstrating the viability of uncrewed, over-the-horizon offshore operations. Its victory in the Shell Ocean Discovery X Prize competition, achieved by mapping 278 sqkm of seafloor in 24 hours using a deployed HUGIN AUV, established its capabilities in autonomous seafloor mapping. Subsequent missions, including the first commercial autonomous crossing of the North Sea and the first remote-controlled inspection of offshore pipelines past line of sight for Equinor, validated its commercial utility. The cancelled transatlantic crossing and the subsequent 22-day Atlantic mission to map uncharted seafloor southwest of England further proved its long endurance, over-the-horizon capability and ocean-going ability. The design's low fuel consumption—using only 5% as much fuel as a comparable crewed vessel—and its ability to operate autonomously or under remote control from anywhere in the world via satellite communications highlight its potential to reduce risk to personnel, decrease costs and lower environmental impact. As the first SEA-KIT X-class USV, Maxlimer served as the template for a configurable mother-ship platform capable of launching and recovering large AUVs, UUVs and ROVs, with Lloyd's Register certification for unmanned marine systems.

Did You Know?

• Maxlimer was the winning entry in the Shell Ocean Discovery X Prize competition.
• A planned transatlantic crossing in early 2020 was cancelled due to COVID-19 pandemic restrictions.