For most navies including the RN, the trend is towards building bigger, more powerful and expensive ‘small combatants’. Unmanned technology offers new possibilities to partially escape this size, cost and complexity spiral. It also can save exposing the crew to danger as well as the cost and size penalty of their accommodation space.
If an Unmanned Aerial Vehicle can be controlled from the other side of the world, there is no reason an Unmanned Surface Vehicle (USV) be built that is big enough to provide the ‘small combatant’ role; to support Ocean Patrol Vessels (OPVs) – perhaps even being built on the same hull design to save development costs, to provide task groups with the greater escort numbers needed for layered air defence (perhaps even taking the ‘point defence’ duties over entirely, allowing the frigates & destroyers to operate further away from the capital ships and auxiliaries), to supplement the Anti-Submarine Warfare (ASW) screen, as well as a many other duties.
Unmanned Underwater Vehicles (UUVs) offer similar benefits in undersea warfare. The cost of operating submarines has risen even more sharply than surface ships and the RN is badly in need of force multipliers. If UUVs can be successfully integrated into naval forces they could have a lot to offer. Communicating through the ocean with UUVs is the biggest hurdle and is much more difficult than with UAVs or USVs. Even communicating with manned submarines has always been a complicated task. If UUV communication or pre-programming issues can be solved, they could be used for; task group defence (freeing up manned subs of their defensive assist duties to focus on their offensive mission), to be forward deployed into shallower waters (where the bigger manned subs are unsuited) and general maritime security missions where they may operate entirely independently. The towed array sonars mounted by current frigates restrict surface ship manoeuvrability and perhaps would be better replaced by UUVs that are independent of the ship and can go deeper and get closer to the targets.
In Service Now
Currently the RN is only using UUVs in the mine warfare role. The Hydroid REMUS 100 was the first UUV adopted by the RN and has been complimented by the introduction of a larger REMUS 600 (called RECCE in RN service). RECCE can go to depths of 600 Meters and is equipped with high-definition sonars used both for hydrographic surveys and to locate mines. They are deployed by the Hunt Class Mine Countermeasures Vessels and provide a 3D picture of the sea bed and the target ordnance. Using this intelligence, another UUV, the SeaFox, can be deployed as for actual mine disposal.
When initially deployed, SeaFox was a ‘once-only’ system but it has now been developed to deliver another detachable mini UUV (called COBRA) this can remotely set explosive charge. This relatively simple SeaFoxCOBRA combination can dispose of mines at a safe distance while allowing re-use of the expensive and numerically finite equipment.
The closest thing to a USV the RN has had in service was the Shallow Water Influence Minesweeping System (SWIMS). A modified remote-controlled Combat Support Boat that towed units generating acoustic and magnetic signatures that deceive the mine into thinking it is a larger vessel. Developed under UOR for use in Iraq, this system is no longer in use but various similar systems have been offered to the RN or are being trialled.
There are various British USV concepts undergoing testing. BAE Systems & ASV have a joint project to adapt a Pacific 24 RIB into USV that will act as protector/escort for the RN’s warships, although limited to carrying sensors and not weapons at this stage. This is not a permanent conversion, but a kit that can be added in to the RIBs to provide enhanced capabilities. An armed USV would be more useful but RIBs are not the ideal craft for mounting weapons. Given that remote-controlled toy boats for children have been available for the last 40 or so years, this kind of development is surprisingly late.
The US-built Rafael Protector USV is a small boat design, mounting an automated weapon system used for patrol and protection of assets in confined waters. A useful, affordable and proven system that would be a useful addition to both USN and RN capabilities.
More sustained effort is being put into unmanned systems for mine warfare, now in their third and fourth generations, they are reaching maturity where although not entirely risk-free, then certainly risks are fully understood. Portsmouth-based company ASV is part of the Thales-BAE consortium that has an MoD contract to develop and deliver the first complete operational unmanned mine countermeasures system, based on their Halcyon multi-role USV.
The RN has also been working with different organisations, such as the National Oceanography Centre (NOC) in order to build up its experience with the operating of UUVs. The NOC UUVs with their long-range, and massive sensor gathering capabilities are particularly useful, as a similar system might well be of use to monitor oceans rather like Airborne Early Warning Aircraft are used to monitor the skies.
Larger USVs that have the potential to increase hull numbers are a way off and will take time but the RN should be getting into the small craft-based USV game. In broad terms the large conventional warship may become a ‘mothership’ to several or even a ’swarm’ of USVs and/or UUVs. Already the next generation of mine warfare vessels being developed under the RN’s MHC programme, aim to not just take ‘the man out of the minefield’, but also ‘the ship out of the minefield’, delegating mine hunting and disposal to remotely operated or autonomous craft.
The RN is now actively looking at expanding its range of autonomous systems to equip both existing ships and future vessels. The Type 26 will have a large mission bay with space and launching facilities for a variety of unmanned systems and expect to see USVs and UAVs become standard equipment for surface ships.
Written by Dr Alexander Clarke.