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Monday, October 17, 2011

Towards tomorrow's minesweeping ops


Minesweeping today

The drones

SeaFox: In 2006, the Defence Logistics Organisation (DLO) announced that it had placed an order worth around £35m for 16 ship sets and a war-stock of expendable mine destructor vehicles of the Seafox One-Shot Mine-Disposal System (OSMDS). Prime contractor Ultra, developer and design authority Atlas Elektronik and logistic support house Babcock was to supply the systems to the RN over a period of three years, starting in 2007.
The contract award followed the successful deployment of the system back in March 2003 during 'Op Telic' when Atlas Elektronik provided the RN with a number of Seafox rounds for operational use in theatre.

An MOD report – entitled 'Operations in Iraq: Lessons for the future' – stated that the one-shot system was 'vital to clearing the waterway leading to the port of Umm Qasr', and that 'it is estimated that the OSMDS reduced the time to neutralise a mine by a factor of four'. The Seafox system offered UK forces a simplified and quicker system, which required fewer operators.

Subsequent evaluation tests since then, both in a tank and at sea, and a live trial of the explosives against sea mines, convinced the MOD of the value of such a system, until the decision was taken, and the OSMDS replaced the PAP Mk 3 and Mk 5 remote controlled mine disposal system vehicles previously used by the Rn’s fleet of MCMVs.

The current SeaFox is actually a family of drones, with two different machines working in cooperation: the re-usable SeaFox I is the “recce” element, used to locate the mine on the seabed, while the SeaFox C is a suicide, one-shot disposal drone which is destroyed together with the mine to neutralize. The SeaFox I, remarkably, can be readied for a new mission in just 15 minutes after being recovered at the end of the previous sortie, while the shaped charge warhead used by SeaFox C is insensitive and allows for safe transport. SeaFox is operational in Sea State 5, and has a range of some 1000 meters.  

SeaFox and a mine on the seabed. Found ya!

Currently, minesweepers deploy SeaFox by a modified crane dropping the drone into the water from the side of the ship. Recovery is done by using a portable command console that a man from the deck of the ship uses to visually drive the drone onto a “fishing net” which is then lifted back up on the ship. ULTRA has a good video showing all the operations, you can see it here.

SeaFox is, currently, the main weapon of the Hunt and Sandown class minesweepers, and the system has been again used, wholly successfully, in the recent Libya operations, when HMS Bangor disposed of a 2500 pounds mine and a torpedo which had been obstructing entrance to the port of Tobruk.


REMUS 100: Again, operations in Iraq in 2003 inspired the evolution of core-role equipment for the RN’s MCM operations. The UK MCM capability deployed during 'Op Telic' was enhanced with the Australian-developed Shallow Water Influence Minesweeping System (SWIMS). SWIMS was developed specifically for this operation and was the coalition's remote-controlled minesweeping equipment designed to operate in the small rivers and waterways in the south of Iraq. SWIMS uses Mini Magnetic Dyads which are towed behind Combat Support Boats to blow up magnetic mines. A mini-dyad is a floating tube, which contains high-powered strontium ferrite magnets. When strung together with a noise maker, a number of mini-dyads are able to fool the mine into thinking that a ship is passing by, causing detonation
The Dyads were acquired from Australian Defence Industries (ADI) as they were the only known influence minesweeping system self-powered and able to operate in a shallow water environment. The mini-dyads were acquired by the Royal Navy to undergo a 12 month testing period, but were rushed into service to deal with the sophisticated Manta mines laid by the Iraqi forces in the Khawr Abd Allah waterway during operation Telic.

SWIMS successfully filled a gap in the RN's shallow water capability, and after being procured against a tight timescale and delivered through the Urgent Operational Requirement process, offered very good reliability in theatre.
Interestingly, the US used the AN/ALQ-219 SWIMS system, towed by helicopters such as CH53 and MH60, a work for which Japan uses the AW101 Merlin. The Royal Navy does not have a great fondness for this kind of methods, also due to its cost, but an Aerial drone is planned as part of the future, stand-off MCM capability. It will be interesting to see what role such drone receives as part of the overall solution.

Building on the success of SWIMS in Iraq, the RN subsequently introduced a very shallow water UUV (from 30m to the surf zone) capability. The experience of operations in Iraq in 2003 is behind the decision to acquire 10 REMUS 100 vehicles. The UUVs were acquired in March 2005 from Hydroid under a £2.7m contract awarded by the UK Defence Procurement Agency. Two further systems, which have been trialed by QinetiQ, have subsequently been upgraded to the same standard as the new vehicles, giving a total inventory of 12 vehicles. QinetiQ and Babcock provide training and logistic supports for the UUVs. The REMUS 100 only weights 37 kg and is designed for operation in coastal environments up to 100 meters in depth.


REMUS 600: The MOD then procured two large UUVs to undertake MCM reconnaissance, hydrographic surveys and environmental monitoring, but they will also be capable of providing more general support to both military and civilian search and salvage operations. The contract was signed in 2007, and saw the acquisition of the US manufacturer Hydroid's REMUS 600 drone, for some 5.5 million pounds. The REMUS 600 vehicles provides a detailed maritime survey and mine detection and classification capability, and was procured for MCM reconnaissance in the 30m to 200m depth range, although the vehicle can operate down to 600m. It is fitted with a range of sensors and runs on re-chargeable batteries giving it an endurance of over 70 hours. The Remus 600 can be deployed from any vessel equipped with a one tonne crane or davit, so it is a quite easily deployable system, although they will almost certainly be mainly operated from the RN's Hunt class minesweepers. The Remus 600 weights 240 kg, and is remarkably similar to a lightweight torpedo such as Stingray, sharing even the 324 mm diameter of it.


The manned part of the deal: The other key tenant of the navy's MCM capability is of course undertaken by the UK Royal Navy's Fleet Diving Squadron (FDS). Limited in terms of numbers, the role of the FDS is increasingly expanding into new areas, and new technology is required in order to accomplish additional roles.

The FDS has a wide remit, including dealing with unexploded Second World War mines, conducting underwater surveys of ports and jetties for deployed RN ships, and clearing waterways and beaches of mines ahead of the arrival of amphibious assault forces or humanitarian aid.

The majority of the RN's operational clearance diving has been to a maximum depth of around 50m. Some aspects of MCM require a deep dive capability, such as mine investigation and exploitation, particularly in the early stages of a campaign when it is important for the MCM Vessels to know what they are up against. They can then alter their tactics accordingly.

Each RN MCMV currently has a diving team on board to undertake mine-clearance operations. As a result of this requirement, an RN diver can expect to spend roughly one-third of their career as a minehunter in the MCMV fleet.

Each MCMV team has three AB divers, one leading hand and one petty officer diver, as well as two specialist mine clearance divers. The divers are there as part of the weapon system of the ship along with the remote controlled mine disposal system vehicles. They are there to identify contacts detected by the ship's sonar. Once a contact has been identified, the diver can lay explosives to destroy the mine.


Towards MHPC and tomorrow’s stand-off minesweeping

The MCM, Hydrographic, Patrol Capability, or MHPC for short, previously known as “C3”, is the multirole mothership and the associated family of unmanned drones and systems that the Navy plan to use to replace its current fleet of minesweepers and the two Echo class survey ships from around 2018. The programme, with a budget currently indicated in some 1.4 billion pounds, aims for some 8 ships, which as the name suggest will combine several roles in one only hull.

They will be rather large ships (2000 to 3000 tons), with steel hulls and thus with nothing to share with current, expensive, plastic-hulled minesweepers. The Hunt class minesweepers have the (questionable) glory of being the most expensive ship per ton built for the RN. They have superb capacity of holding a steady position even in rough waters, and their Glass-Reinforced Plastic hulls allow them to slip even into minefields. However, GRP is of course not as good as steel for seafaring and for resistance, and the Hunts and Sandowns aren’t the best of ships to sail in rough seas. They are also slow and relatively short legged, which makes their deployment to the Gulf more difficult. The US Navy has been using Float On – Float Off (FLO-FLO) vessels for long range transfers of minesweepers, but this of course is not financially viable for the UK.

The MHPC will be larger, built out of steel, and with a greater range and endurance, suitable for Ocean Patrol and Maritime Security taskings, as implied by the “Patrol” part of their name. They will be ships more capable across the range of roles, and far more deployable. But they won’t have the Hunt’s capability of going into minefields.
Nor does the RN want ships to go into minefields anymore. Ever since 2005, MCM ops are increasingly of a stand-off nature, and the Combined Sweep kit used by Hunt minesweepers has been retired.   

The MHPC will have to do its MCM work from a safe, stand-off position, which might be miles away from the minefield to remove. To do this, and to cover all other missions it is asked to take over, it will have to be able to carry and operate suites of modular, remotely-controlled or autonomous kit.  

ATLAS Elektronik is the MOD’s selected main partner for working towards such an unmanned MCM “systems of systems”. If the plan is not changed, before this month is over, ATLAS Elektronik and the MOD / Royal Navy will stage a week long test and demonstration campaign, to validate the latest solutions and continue to refine the concept.

Such week of activies would build on the success of another demonstration, which ATLAS staged last July, when the company showcased its C-IMCMS system and concept at its test site at Bincleaves, Weymouth on south coast of England. Representatives from Germany, Great Britain, Canada, the USA, Belgium, Turkey, Saudi Arabia and Thailand took part. During this demonstration, there was no mothership, but a containerized command centre deployed ashore, and a variety of drones deployed again from ashore. The new demonstration of this month, if confirmed, should be staged from a ship, probably a RN Hunt minesweeper.

The July demonstration, anyway, was already of capital importance, as it proved the immediate feasibility of a number of concepts indispensable for the successful prosecution of the MHPC vision. The C-IMCMS (Containerised Integrated Mine Countermeasures System) consists of several systems:

-          a portable combat management system as well as the analysis software CLASSIPHI for post mission analysis of side-scan sonar data, which, installed in a TEU container, would be easily transferable to any vessel with sufficient space provision and adequate power interface
-         the unmanned surface vessel (USV) FAST, developed by ATLAS under a 2007 contract awarded by the UK MOD
-         the autonomous underwater vehicle (AUV) SeaOtter Mk II;
-          the mine disposal system (ROV) SeaFox

FAST (Flexible Agile Sweeping Technology): this USV was developed by ATLAS ELEK-TRONIK UK to carry out acoustic and magnetic influence sweeping, in which a towed body is used to emulate the corresponding signatures of a ship and thus cause the mines to detonate. The FAST was funded by the MOD with the aim of developing a replacement for the Combined Influence Sweep (CIS) capability which was dismissed from the Hunt class minesweepers in 2005. It has yet to enter service, but was trialed successfully in several occasions since 2009, and it is being used actively to shape the future requirements and systems.

According to a Sunday Mirror article, the FAST drone will be ready for adoption in service within the next two years. But the article is wrong on the 600-jobs loss and on the Hunt retirement rumor. This is a conclusion too bold: the FAST is actually intended, ever since it was ordered, to EQUIP the Hunt class minesweepers to replace them in the dangerous Combined Sweep work, not to REPLACE the vessels and their crews whole. In this sense, Babcock did already prepare plans for the modifications to the rear working area of the Hunt class, which will enable each Minesweeper to carry and deploy a couple of FAST drones.  So, while some jobs will be perhaps lost, the scenario is very different from that painted by the short article. Far more jobs are effectively at risk come 2018, when the 8 MHPC eventually replace 14 Hunt and Sandown vessels, but this is another story, and one too far away in time for advancing hypothesis about. 

Babcock has already made proposals for modifications of the rear area of Hunt minesweepers, to allow the carriage and deployment of two FAST drones

Since contract award, the role of FAST has expanded. From a more sophisticate, non-UOR SWIMS, it became an unmanned workhorse acting as a mothership itself to a range of other drones. During the July demonstration, in fact, FAST was used to remotely deploy SeaFox. SeaFox can work some 1000 meters away from the deploying platform, so it is essential to have a “taxi” platform capable to deploy it at distance and fitted with radio for relaying data to and from the SeaFox drone over the miles separating it from the mothership. And this was demonstrated in July, proving that one of the most challenging aspects of the whole concept is perfectly feasible, and indeed already working. SeaFox was for the first time remote-controlled from the container based ashore through a combination of a radio link to the FAST USV and a fibre-optic cable from FAST USV to Seafox. Both sonar and video data captured by SeaFox were transmitted in real-time via radio link.

The FAST (Flexible Agile Sweeping Technology) system is being developed by an industry team led by Atlas Elektronik UK, and has completed an Interim Design Review for a mine countermeasures (MCM) Unmanned Surface Vehicle (USV) demonstrator system under development for the UK Ministry of Defence (MoD). The Atlas-QED industry team also includes EDO Corporation and QinetiQ. The consortium won a GBP4.3 million (USD8.6 million) contract from the UK's Research Acquisition Organisation in May 2007 for the two-year Technology Readiness Demonstrator (TRD) programme, known as Flexible Agile Sweeping Technology (FAST), which culminated in trials aboard HMS Ledbury in mid 2009.

The FAST platform is a modified Logistic Support Boat (LSB-R), sharing the hull of the proven, in-service Combat Support Boat.  The CSB is a powerful, versatile craft whose major role is to support both bridging and amphibious operations.  The FAST platform builds on the success of the CSB while incorporating significant performance improvements to meet the demanding requirements of this programme. 

A graphic of FAST, shown in its main roles: as "taxi" for SeaFox, and as Combined Influence Swep drone
 
The FAST system’s main features are:

  • Flexible
    • Configurable 2/3-Electrode magnetic sweep and Integrated Coil
    • Cable design includes replaceable electrodes
    • Easily configurable for alternative noise source(s)
    • Design accommodates multiple towing configurations
    • LSB-R - New Engines/Jets, Hamilton blue ARROW Control
    • Clip-on sweep system
    • Integrated Sweep Payload control

  • Agile
    • Remote/Autonomous Control
    • Combined Planing/Displacement hull
    • Revolutionary Waterjet/Control system

  • Sweeping
    • Enhanced ITT Power Generation Unit
    • Waveform Generation
    • New Sweep Cable design

  • Technology
    • Fly-by-wire
    • Open Standards
    • Common Interfaces
    • Collision Avoidance

Evolving the SeaFox: this year, SeaFox has evolved. Presented also at the DSEI show, the new concept was introduced by Atlas Elektronik, teamed with ECS Special Projects Ltd. The new idea was to install a stand-off EOD killer effector on the re-usable SeaFox I. The COBRA (Clip-On BX-90 Re-loadable Assembly) can be fitted to the re-usable SeaFox vehicle offering Explosive Ordnance Disposal (EOD) capability from surface to 300m depth, removing the need for the SeaFox C, and providing a reusable disposal system  offering multiple target prosecution / multiple target initiation by remote means. In addition, SeaFox has now been evolved to be deployable even from a RHIB, allowing stand-off, automated operations away from the mothership.

These two new capabilities will be priceless, and in addition to FAST, will provide the Royal Navy with an effective, wholly remotely-operated mine disposal capability. An unmanned FAST, properly kitted, could deploy from the mothership, to which it’ll be connected by radio link, enter the minefield, and deploy (and then recover) the SeaFox I drone fitted with COBRA for the disposal of the threat. The advantage of COBRA is also in the inferior time that will now be required for disposal, as the RECCE element will be now capable to dispose of the mine by itself, without need for a second vehicle to be launched and vectored to the target. SeaFox is now an “hunter-killer” asset, evolving in the same way the Predator UAV has, by changing from an unarmed scout to a long-endurance killer.

Cobra is a “mask” worn on the front end of the SeaFox vehicle. For mine disposal, Cobra attaches itself to the mine while the SeaFox vehicle manoeuvres away. Attachment can happen in three ways: nail attachment units, harpoon for soft-skinned targets, and magnetic grabs. In this way, only the COBRA is disposed of, while the SeaFox I returns to the ship for recovery, providing a considerably cheaper and easier solution for disposal of mines.


An unmanned, Stand Off MCM solution taking shape: So. REMUS 100, 600, SeaFox, perhaps “tomorrow” used with COBRA, and FAST seem to be an excellent “terminal” section of the Minesweeping operation. They also are a mature and proven solution, which can provide a very solid base for development of a containerized, ship-agnostic MCM capability for the future navy. Arguably, these systems are modern enough that at least some of them are very likely to migrate from the current Hunt ships to the MHPC, assuming that the MHPC is not delayed by decades as sadly happened with recent ship programmes.

But, of course, before employing these systems, we have to discover where the minefield is, something that, currently, is done largely by the sonar of the minesweeper. If we have to remove the minesweeper from the equation, we have to offload the sonar payload to a remotely-operated, unmanned platform as well. MHPC or Type 26 will of course have sonar themselves, but we still are not going to want them scouting in a possibly mined area, for obvious reasons. The excellent, Thales 2193 sonar, adopted in 2004 for the Hunt fleet, has the capability to detect and classify an object the size of a football at a range up to 1,000m, but this distance is far shorter than the desirable one for the future.

ATLAS Elektronik, has demonstrated to the MOD their own solution, which is based on their Sea Otter MK2 autonomous underwater drone. This 1-ton drone can be equipped with a high-resolution side-scan sonar. In addition, it can be fitted with other mission payloads, including a powerful MCM synthetic aperture sonar, as it has a 160 kg useful payload. It has a search endurance of 24 hours at a 4 knots speed. It can dive to 600 meters, and is some 3,45 meters long. Once a drone was selected and kitted, it would need a containerized launch and recovery solution, to make it easily deployable on the Mothership, and this should not be an issue. In this sense, Think Defence’s own article about Minesweeping can provide more info. 

The Sea Otter MKII is a solution for the problem of finding the mines with sonar searches.

Other possible platforms for the role could emerge. One alternative could be BAE System’s Talisman. But a larger Unmanned Surface Vehicle, launched from the mothership, could also be the way to go to provide a platform to send in harm’s way, carrying the sophisticate sonars, such as the Thales 2093 variable depth sonar used on current minesweepers. Indeed, France looks set to follow this very path, even if FAST, due to its smaller sizes, has the advantage of being more readily carried by pretty much any kind of vessel, including the Type 26 frigate in the Mission Bay aft. The French unmanned boat is much larger, and could pretty much only be carried by the 2-3000 tons motherships they envision to replace their own minesweeper fleet.


French connection

MCM systems are an area of possible collaboration highlighted following the Lancaster treaty between UK and France, and in the sea environment, there is a surprisingly similar timeframe and requirement which could make such collaboration possible on a very large scale.

France is in fact planning to start replacing its current MCM fleet in 2018, with a fleet of multimission motherships of as many as 3000 tons, employing a standoff suite of MCM drones and systems. Roughly, the same target that the Royal navy is pursuing. The French effort comes under the name Système de Lutte Anti Mines – Futur (SLAM – F) and aims to a “system of systems” capable to operate in a minefield 10/14 miles away from the mothership, even in Sea State 5.

Following studies started in 2009, France is currently considering a mothership of around 3000 tons, which will deploy a large multifunctional Unmanned Surface Vehicle “taxi” that will deliver the Mine Countermeasure assets from the mothership to the danger zone. 
The target is to build some 5 Motherships, each capable of deploying two or three “Taxi” vehicles. They are considering a catamaran vessel for the mothership role, offering higher speed than current Eridan minesweepers and larger deck and working areas. 

And this might be an issue: even if the MHPC design of the Royal Navy is far from taking on a concrete shape, a catamaran solution might cause some eyebrows to rise in a traditional organization where monohulls are preferred.

Another possible issue on the way of collaboration is represented by the philosophy and sizes of their Unmanned Surface Vessel, as it is a stealthy catamaran displacing some 24.5 tons, 17 meters long and 7.5 meters wide, presenting some challenges regarding launch and recovery, particularly in rough weather, and anyway making the USV hard to deploy with anything other than its intended motherships, differently from the much smaller FAST. France, in studies dating back to 2009, assumed that the final USV design would be made compatible with the Mistral LHDs as well, but carrying USVs would still almost certainly require the sacrifice of some of the landing crafts, making it a far less than optimal solution.

Of such USV, they have built a prototype, already being tested at sea, the Sterenn Du. The unit was launched in 2010, and this year it should move into more advanced testing, with a towed array sonar planned for it, plus a number of submarine drones to be used for validating launch and recovery systems and procedures.  

There is obvious difference between the Sterenn Du and FAST


FAST and Sterenn Du are very different, but share the same notional mission (even if, at the moment, it does not appear that the Sterenn Du would run Combined Influence Sweeps, differently from FAST) as remotely operated “taxi” for underwater drones. They both are set to be the vital link between the mothership and the deployed underwater drones, with which the mothership very hardly could communicate without such a relay node in the middle. SeaFox, after all, works only up to a kilometer away from the launching ship, and the standoff operations envisaged for the future require the mothership to stay well further away than that. They have both advantages and faults: FAST is small, and this allows it to be employed also from the future Type 26 and possibly by other vessels of the Navy. But its small sizes are also a limit to what can be installed on it.

However, there is certainly scope for collaboration. France is trying to fuse its SLAM-F with the European Defence Agency’s project of studies into future MCM means, which involves some 13 nations, reportedly awakening some real interest, which is only going to get greater when the Sterenn Du eventually begins to successfully prove the concept and to do its job.

Ideally, collaboration could be expanded to the Mothership, with each other’s design being informed by the work of the ally. And possibly, in time, UK and France could end up deciding to pursue a single, high-commonality design for the vessel, in order to pursue savings and financial efficiencies in the building phase that both countries direly need. Which does not necessarily mean aiming for a “no differences” common solution. To be not just safe from problems stemming from national requirements incompatibilities, but also exportable, the new system should be as modular as possible, allowing each nation to, for example, select its own fit of radars, weapons and even engines for the Mothership, and of course drones for the proper MCM suite.

This year, anyway, and very possibly this very month, should provide us further news about the new MCM concepts, and about SLAM-F. It will be interesting to read into the results of the ATLAS demonstration to the MOD, when news come out.

I’ll ready to post all significant updates when time comes!   

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