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Hunt, the Replacement

Minehunters – they’re ugly, made of plastic, full of muppets 1 and getting old. This is why we should replace them.

Navy discussions at the moment inevitably gravitate towards carriers, frigate numbers, patrol vessels and replacement submarines. However, one type of ship often gets overlooked – the humble minehunter.

February’s NAO report briefly mentions that there is to be no replacement for the current ships:

“The Navy is also due to lose its mine-hunting capability in the early 2030s. Although the Navy believed that this capability needed to be addressed in the 2019–2029 Plan, it does not include funding to extend or replace this equipment. The Transformation Fund did, however, make up to £31 million available to explore a potential new way of delivering this capability.”

National Audit Office

My fear, and the reason for this article, is that the RN’s mine hunting vessels could be sacrificed at the altar of technology for a cheaper, but not better, solution. This would be bad news for a number of reasons listed below in what I think is a priority order.


If the RN’s current fleet of eleven operational ships are not replaced, the UK would suffer an almost total loss of ability to detect and destroy mines. Mines remain a simple and very cheap way to wage war. Laying them can range from ‘accidentally’ dropping one in a chokepoint to cause confusion, to deliberately placing some in a shipping lane, either to destroy a tanker or as a tactic to shepherd a vessel somewhere else (such as a fast attack craft kill box), to indiscriminately deploying 100s to totally close a shipping route. The amount of time required to clear a shipping lane isn’t an exact science as it depends on significant variables such as length, width of swept channel and % clearance confidence.

Clearing something like the Strait of Hormuz such that it could be reopened for merchant traffic should be thought of in terms of weeks and months, not days. The Iranians have proved only recently that mine warfare is a live tactic of theirs which, were they to deploy with determination in the Strait of Hormuz, would have a significant effect on the global flow of hydrocarbons and therefore economy. Right now, the RN is the only navy in the world that has the expertise and mass to deal with an attack on this scale.

Mines range in type from the classic WWII horned contact mine to extremely high-tech variants that bury themselves in the seabed, count the ships as they pass overhead and deploy on a rocket when the largest one is above. Simple or sophisticated, the effect on impact is pretty much the same as both the USS Princeton and USS Tripoli found to their cost during Gulf War 1.

USS Princeton (top) and USS Tripoli both hit by mines in Gulf War 1 proving the adage oft loved by the mine hunting community, “everyone can be a minehunter…once”. Both ships were dead in the water after the impact and required extensive repairs, effectively ending their war. Amazingly, there were no fatalities.

There can be no doubting the threat either. An article in Naval Technology says:

“Since 1945, mines have sunk or damaged more US Navy vessels than all other kinds of weapons combined, and there is strong evidence that a number of nations, including China and Russia, view them as a vital element in their naval warfare doctrine.”

Only today an article has emerged of free-floating mines being discovered in the Red Sea off the coast of Yemen. Areas such as this, thousands of miles from established lines of support, would most effectively cleared by an organic and self-sustaining capability.

Final point on mine warfare. Whilst it’s almost inconceivable that an adversary would lay mines around the UK or worse, in one of our ports, what if they did?

There is no doubt that mine hunters are vulnerable. They have reduced situational awareness and communications suites when compared to their frigate and destroyer counterparts and their weight of fire, whilst significant, is of limited use against a determined missile threat.

If it got really nasty, and they were required to clear a channel in a heavily contested environment, then they would need protection from a frigate or destroyer that would struggle to operate safely due to the very mine threat that they are there to counter. This is a conundrum that has yet to be fully solved.


The Royal Navy’s mine hunting capability buys it huge equity with the US. In a resource environment where matching their deployment levels to even 10% is a challenge, the search for niche capabilities that they don’t have is embedded in most planning efforts.

Here, we have one. There hasn’t been a US leader from Obama to the current 5th Fleet Commander who hasn’t looked admiringly at the four vessels permanently on operations in Bahrain before heading off to see why they have been so overmatched.

I have no doubt that this unique capability resulted in more surveillance assets being allocated to UK forces during events in the Strait of Hormuz last autumn. Unfortunately, these vital trade-offs never appear on a budget sheet.

Q routes

“A system of pre-planned shipping lanes in mined or potentially mined waters used to minimize the area the mine countermeasures commander has to keep clear of mines in order to provide safe passage for friendly ships and submarines.” (JP 3-15, US DoD).

Q routes, and what goes on in them is sensitive, but let’s say you wanted a route cleared so that “friendly ships or submarines” could use it as quickly as possible. If you’ve checked that route previously for mine-like objects (rocks, discarded anchors, shopping trolleys etc) then clearing it ‘for real’ is much quicker. This is important and happens a lot, all round the UK and elsewhere and has done for decades. No one else can do it.

The classic WW2 contact mine
A manta mine (made of GRP to foil sonars)


Divers are an extraordinary breed of human; part sailor, part explosives expert, part vanity project, all brave.

I would posit that this branch is the standard bearer, across all of Defence, for routine jeopardy. They are trained to dive to over 60 meters in zero visibility, in freezing water whilst breathing a hideous nitrox mix even before they get to their objective which might a mine with anti-diver countermeasures fitted.

No matter how good emerging technologies get, the requirement to occasionally put this type of person on the mine will persist. More visibly, three Fleet Diving Units are on immediate notice every day to diffuse assorted ordinance and bombs around the UK. This capability was activated almost daily as the approaches to Portsmouth were dredged in preparation for HMS Queen Elizabeth’s arrival and even more visibly in Jan 2017, in Westminster:

Unexploded WW2 bomb briefly bought London to a standstill in Jan 17. Defused by Commander Del McKnight and members of his Fleet Diving Unit.

The diving branch could be a case study in how if a small, highly trained capability were to lose its primary operating platform, the subsequent loss of structure would cause it real issues and could even spell the end of it.

Balance and mass

The First Sea Lord recently stated that the RN’s first priority is underwater warfare. This is normally associated with the submarine threat in the North Atlantic and the RN’s ability to maintain the Continuous at Sea Deterrent (CASD).

However, mine warfare should form part of this equation particularly when it is directly linked to both (see Q route). They also have utility as a patrol vessel. They may be slow but when fully armed, they carry a significant weight-of-fire.

For years they contributed significantly to the UK’s fishery and Northern Ireland protection efforts. They have even escorted Russian ships through the UK’s area of interest (although there is a debate to be has to whether they are suitable for this given how easily they can be outrun).

Nevertheless, in an era where hull numbers are at an all-time low, can we afford to lose another 11 without replacement? The fleet right now, whilst low on mass, is nicely balanced across all capabilities. Loss of these ships would upset that balance.

Commanding Officers

Commanding a ship is an unusual mix of leadership and technical expertise in a uniquely exposed environment. The idea of developing those skills in a smaller platform before moving on to something larger is as old as the navy.

The great historical naval leaders such as Nelson, Collingwood, Fisher, and Beatty all cut their leadership teeth in commands of various sized ships. You won’t find a flag-ranked warfare officer in the current navy who didn’t drive at least one ‘small’ ship before assuming higher command.

As ships become more and more expensive, physically learning how to berth and handle a much cheaper one first is a good idea as well. Take these platforms away and you remove this element of experience and development from the future leaders of the navy.

What needs replacing?

The RN operates two types of minehunters, the Hunt Class (named after various hunts around the country in what was clearly a different time…) and the Sandown Class. The first Hunt class mine counter measures vessel (MCMV) was commissioned in 1980 and was the RN’s first ‘plastic’ ship (Glass Reinforced Plastic (GRP) to reduce magnetic signature).

As the largest GRP ships in existence, they were cutting edge and used to proudly boast that per yard, they were the most expensive ships in the RN. They could ‘hunt’ mines using a forward-looking sonar and ‘sweep’ for them using wires, magnetic loops and acoustic generators streamed over the back end. Sweeping in a heavy sea-state was a hairy sport even before factoring in that one had to pass over the mine before it could be destroyed.

Fortunately, sonar technology improved such that by the late 90s, this technique had become obsolete and ‘hunting’ became the sole method of detection. As a side-note, early Hunts had possibly the worst maritime engine ever, the Deltic diesel.

These engines were built to run in aircraft (unbelievably) and then in trains, both at high & steady revs. The stop/start (and salty) nature of maritime operations made them break and/or catch fire with remarkable regularity. If fact, Deltics made T45 engines seem positively Rolls-Royce…

Like their more expensive younger relatives are due to, Hunts have now all had their Deltics replaced by engines that actually work making it, as is so often the case, a very capable vessel as it nears the end of its life. The Sandown class came along in the early 90s and with their combination of their fancy variable depth sonar and flappy-paddle voith-schnieder propulsion were generally sneered at by the hair-chested Hunt community.

Some amusement was to be had from the early sonars which did indeed vary their depth, often without any human input. “How much does your ship draw? Are you sure?” was an ‘amusing’ question to ask an early Sandown captain. The sonar problem was quickly fixed but Sandown’s still don’t have propellers and are therefore not to be trusted.

More seriously, the general consensus is that in shallow water the Hunt’s sonar upgrades have given it a detection edge over the Sandown but that the latter’s variable depth sonar makes it better in deeper water. This makes the two-of-each combination permanently stationed in Bahrain very effective.

The future

There are lots of options for replacing these vessels when they finally go out of service. The Future of Royal Navy Minehunting, written in 2018 by Save The Royal Navy, articulates them well.

In broad terms, it is fair to say that one day there will be a technical solution that negates the need for crewed vessels. However, one day the oceans will be transparent and we won’t need submarines, all aircraft will be pilotless, hypersonic missiles will render carriers useless and the battlefield soldier will be a robot.

But not yet.

Detecting and dealing with mines remains a slow and complicated business that requires persistence on task, large amounts of power (for the sonar) and significant experiential judgement. Attempts to substitute these with innovative solutions, and there have been many, have so far always resulted in a less capable solution in one or all of these fields.

Airborne solutions; divers deployed in rigid inflatables; Type 31s with a MCM mission bay and remotely operated submersibles are all either in use or on the table but thus far all have significant vulnerabilities and/or weaknesses.


Doing the sort of maths that the MoD finance teams rightly despise is still a useful exercise. Each Hunt cost c£40 million in 1980. This equates roughly to £120 million today. 12 new ships would therefore cost c£1.5 billion, or the cost of single Type 26 Frigate. Operating costs are roughly £3 million a year compared to nearly £15 million for a T45. It doesn’t really matter how precise these figures are, MCMVs are very cheap.


The Royal Navy’s mine hunting fleet provides the UK with a world-leading warfighting capability that is on essential live operations in the UK and elsewhere every day of the year. It buys the RN considerable equity with our allies whilst providing both balance and mass to what would otherwise be a top-heavy fleet. As a training tool for both divers and future commanders it is invaluable.

Twelve replacement ships would maintain all this for roughly the price of a single Type 26.

They all go out of service in the next 10 years and thus far, I’m not hearing much noise about their replacements. I hope this changes in the near future.

Commander Tom G Sharpe OBE RN (Retd)

Tom Sharpe is a freelance communications consultant specialising in managing reputations and capacity building for complex and often contested organisations. Prior to this he spent 27 years in the Royal Navy, 20 of which were at sea. He commanded four different warships; Northern Ireland, Fishery Protection, a Type 23 Frigate and the Ice Patrol Vessel, HMS Endurance.


  1. A not-so-flattering nickname for mine warfare ratings.

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