Demand for dependable research, survey and intervention vessels is booming, positioning this sector as one of the fastest-growing in the maritime industry. This demand is being driven by numerous factors, including: a surge in offshore wind farm projects, necessitating detailed seabed mapping and environmental impact assessments prior to turbine installations; ongoing exploration needs within the oil and gas sector; and the growing requirement for vessels capable of supporting research projects focused on ocean health, climate change and biodiversity.
Formed in 2008, Norwegian operator Reach Subsea specialises in deploying work-class ROVs to gather ocean data for clients. “We were looking for something that could make us a bit more competitive in this market,” Bjørg Mathisen Døving, VP for the REACH REMOTE fleet at Reach Subsea, tells The Naval Architect, “and we also wondered why we were utilising a big vessel for what were quite easy ROV deployment tasks.” An encounter with Kongsberg Maritime in 2015 led Research Subsea to consider the use of a remote-controlled USV.
This uncrewed craft would not only taxi a work-class ROV from site to site, but also act as an ‘energy carrier’, providing the power required by the ROV for its offshore tasks. The USV and ROV would be operated from remote operations centres (ROCs), on land or on another ship. This concept would evolve into Reach Subsea’s REACH REMOTE 1 USV, which was launched in January 2025.
“We started off with a pilot programme, using a pool at the Norwegian University of Science and Technology in Trondheim, where we tested the vessel’s hull and the ROV, and their movements,” says Døving. “From there, we worked with Kongsberg on a field study. At Reach Subsea, we have years of experience and knowledge of ROV operations, so we were able to add a lot of details for the final concept, especially regarding the onboard ROV launch and recovery system [LARS].”
For Døving, the vessel offers numerous benefits compared to traditional crewed vessels. For instance, the smaller overall vessel size (think no need for heads, crew berths, fresh-water tanks or a galley), combined with the use of hybrid electric propulsion, spells lower rates of fuel consumption per operation, minimising the boat’s environmental impact. Reach Subsea and Kongsberg restricted the USV’s length to just under 24m, to meet the UK Maritime & Coastguard Agency’s (MCA’s) Workboat Code 3 requirements.
From a safety perspective, moving operations to onshore ROCs also removes the dangers faced by human crews in rough offshore environments. Additionally, as smaller, quieter vessels, USVs significantly reduce underwater noise, minimising disturbance to sea life.
There is also the benefit of reducing unplanned downtime by using shipboard predictive maintenance technologies to keep tabs on the performance of vital equipment and systems. Moreover, remote-controlled operations open up new job opportunities for a more diverse workforce, including people who may be restricted from travelling offshore, due to disabilities or family commitments, for example.
Marthe Kristine Sand, Kongsberg (left) and Bjørg Mathisen Døving, Reach Subsea: the companies collaborated on the development of the USV for nearly 10 years
Kongsberg then contracted shipbuilder Trosvik Maritime to fabricate the USV. This was an unusual arrangement for Kongsberg. As Marthe Kristine Sand, Kongsberg senior project manager, explains: “Normally, Kongsberg would supply the systems directly to the yard for outfitting – but this time, the yard acted as our subcontractor. This meant we were able to offer REACH REMOTE 1 as a complete package, including the vessel, its systems and navcom package.” Sand, Døving and Kongsberg senior ship designer Erik Leenders (who headed up the USV’s design) oversaw the development of the newbuild from the earliest design phase to the fabrication stage.
REACH REMOTE 1 isn’t just dependent on its ROV for underwater tasks; the USV can also perform its own surveys, using two Kongsberg EM2040 multibeam echosounders and a Topas PS120 sub-bottom profiler, which can gather data up to 500m-deep. The ROV is an electric work-class ZEEROV model, produced by Norwegian tech specialist Kystdesign. Rated 150hp (112kW), the vehicle measures 2.75m x 1.7m x 1.69m, weighs 3,800kg and can carry up to 600kg of sensors and scientific equipment. The ZEEROV can descend to depths of 2,000m, and has been specially developed for 30 days’ worth of prolonged immersion, matching the USV’s range.
Described by Leenders as “the heart of the vessel”, the ROV LARS has been customised for crew-free operations, deploying the ROV beneath the surface through a 5m x 3m moonpool. Døving adds: “The umbilical that runs with the ROV is also a lifting umbilical with a SWL of 8.6tonnes. So, in principle, it acts like a winch. We could use the LARS with any drone or underwater vehicle that fits.”
The engine room houses two Volvo Penta diesel engines with permanent magnet motors, which provide power for both the vessel and the ROV. Kongsberg supplied the USV’s two lithium-ion battery banks, which can be used for peak shaving and added redundancy in the event of engine failure, or to power the vessel in pure-electric mode. Running solely on batteries would limit the vessel’s endurance somewhat – perhaps to between half a day and a day, Leenders estimates – but this is an important feature should the boat have to enter eco-sensitive areas. The USV uses two ZF azimuthing thrusters, one fore and one aft, to maintain its DP2 dynamic positioning capability.
For the full, in-depth story, including sea trial results, future forecasts and technical particulars, check out the March issue of The Naval Architect
