Naval mine hunters say that, “a mine is a terrible thing that waits.” It waits and waits till it destroys/damages a naval vessel or is destroyed by the naval mine hunters. During Operation Starvation in 1945, the US Navy dumped close to 25,000 mines on the vital water routes and ports to disrupt enemy shipping and starve Japan. Hundreds of mines remained in the waters for decades and endangered shipping during peacetime. Sea mines are full of stealth and deceit, lurking dangerously to destroy/damage and disrupt naval operations and merchant shipping. Naval mines are an invisible enemy which allows any maritime nation to defend itself, regardless of its naval capability. They deter and push underwater and surface navy to move away from the shoreline towards the open sea.

Naval Mines

The basic sea mine is detonated when a ship comes in contact with it and causes an electrical circuit to be completed that activates the explosive through a highly-sensitive fuse or initiator within a operating radius of 50 to 60m. Sea water is very corrosive and effects every object in the sea including mines which became ineffective or un stable after some time. The problem of longevity was solved as early as the 1870s with a device called the Hertz Horn which contained a vial of conductive liquid. The vial broke due to the contact of the ship with the horn, it would complete the circuit which initiated the explosion. The same principle was used for bursting artillery shells in the air where the vial broke due to the set back force and the circuit was completed thereby initiated the bursting of the shell. Many countries developed influence mines which employed a variety of sensors that activated the mine when a ship sailed in proximity to it. Sensors used are based on engine sound, pressure of waves due to the movement of the ship and magnetic field or a combination of these methods of detonation. There are other varieties like the Limpet mine which is manually attached to the target by magnets; command detonation mines; Rocket mine; Torpedo mine; Moored mine; Dummy mine and so on. The moored mine is deployed where water is too deep for bottom mines and normally uses a combination of acoustic, magnetic and pressure sensors or even more sophisticated optical shadows or electro potential sensors. Recently a new class of attacking mines have been developed which is a combination of a mine-carrying platform and a torpedo or a missile system. Mines can be planted by aircraft, submarines, surface ships, underwater robots, and frogmen, as well as merchant ships, fishing ships, ferries and motor boats. Some of the current and future developments are greater operating ranges, sensitive to fast-moving targets including submarines; modernisation of current exploders and development of multipurpose exploders; development of multipurpose transportable mines; reduction of target attack time and simultaneous enhancement of reliability and noise immunity of mines and so on.

Concept of Mine Countermeasures (MCMO)

The MCMO Operations are inter connected operations that enable naval forces to counter the mine threat and are:

Mapping, Survey and Intelligence Operations. It cannot be predicted as to the exact area where naval operations will be undertaken but it certain that naval forces will encounter technically sophisticated mine in the littorals and other areas of interest. Thus during peacetime sustained effort is required for bottom-mapping and environmental survey along with an active mine threat intelligence to provide comprehensive and exhaustive data collection counter mine operations. This requires high level of Command, Control, Communications, Computers and Intelligence(C4I) and data analysis programmes.

Surveillance Operations. It is essential to continuously update the data base with adequate surveillance and intelligence assets. This will result in acquiring an updated and increasingly detailed assessment of mine production, stockpile locations, mine-laying platform locations, and readiness of a potential adversary’s mining force.

Organic MCMO. The goal of organic mine countermeasure operations is to enable naval forces to conduct their warfighting missions without being exposed to the risks of operations in mined waters until the arrival of dedicated MCM forces. This will help the non MCM force to shape the battle space by detecting and avoiding operations in mined waters.

Dedicated Mine Countermeasure Operations. Dedicated MCMO are conducted to clear enemy minefields, to further shape the battle space, and to project power from the sea. Airborne, surface, and shallow water MCM forces supported by Explosive Ordnance Disposal divers and Naval Special Warfare forces, are used to conduct dedicated MCMO.

Mine Countermeasures Vessel (MCMV)

MCMV is a naval ship designed for the carrying out the twin role of minesweeper and mine-hunter. It thus locates the mines then destroys them. Operation Overlord was the largest opposed amphibious assault of the Second World War (June 6, 1944). It involved crossing the English Channel by more than 5,000 vessels and about 160,000 troops, and was the most difficult and costly MCM operation. The extensive mine field and obstacle clearance was carried out by more than 300 MCM ships, swimmers, and large number of supporting forces. Such a large mine sweeping operation will probably never be seen again. An example of US Navy’s MCM-1 is given briefly:

MCM and MCM-1 (Avenger) class of ships. The current MCM ships are capable of supporting all mine-hunting aspects to include detection, classification, identification and destruction. However the MCM-1 class can carry out minesweeping which includes mechanical sweeping against moored mines and magnetic/acoustic combination influence sweeps against moored and bottom influence mines. The MCM-1 has the AN/SQQ-32 mine-hunting sonar for mine detection and classification. It was developed by Raytheon and Thales Underwater Systems (formerly Thomson Marconi Sonar)and currently features on all MCMVs of the US Navy. It relies on the AN/SLQ-48 tethered mine neutralization system (MNS) to identify and render inoperative sea mines. The AN/SLQ-48 is a recoverable, submersible which carries high-definition sonar for reacquisition and a low-light-level TV and floodlights for identification of the target. The MNS places an explosive charge near the bottom or moored mine target to destroy the mine in place. It receives its commands and power from the mother ship. A closed-loop degaussing system is being developed for the MCM-1 to lower the ship’s magnetic signature and reduce the frequency of calibration at degaussing ranges. Degaussing is a method to decrease or eliminate a remnant magnetic field.

Other Platforms used for MCMV role. Unmanned Underwater Vehicle can be of immense value to the MCMO. MCMO can be carried out by helicopters like Sikorsky’s S-80/MH-53E (Sea Dragon). The MH-53E is a multipurpose helicopter employed for vertical replenishment and airborne MCM. It has three engines, equipment for towing the EOD Mk 105 hydrofoil anti-mine sled, AN/AQS-14 side-looking mine-hunting sonar, a variety of mine sweeping systems including Mk 103 mechanical sweep, Mk 104 acoustic influence sweep, Mk 106 combination acoustic and magnetic influence hydrofoil sled, AN/SPU-1/W Magnetic Orange Pipe magnetic influence sweep (for shallow water), AN/ALQ-141 dual acoustic sweep, A/N 37U deep mechanical sweep, and Mk 2(G) acoustic influence sweep. The Explosive Ordnance Disposal (EOD) diver system and marine mammal system, play a key role in offshore mine warfare operations. EOD MCM detachments are employed to identify, neutralize, and exploit mines as well as participate in post-interdiction intelligence collection. Dolphin’s biological sonar called echo location, is good at detecting mines. The Californian Sea Lion also displays similar traits thus the US Navy has launched a unique Naval Marine Mammal Programme to train dolphins and sea lions to detect mines and other objects. The EOD diver system and mammals are combined to work as a team.

Indian Perspective

India inherited mine sweeper vessels from UK which were wooden hulled vessels and were subsequently replaced by Soviet origin minesweepers (Pondicherry class) in the 70s. However, the break-up of former Soviet Union created serious problems of maintenance and spares support which was also applicable to all military hardware of Soviet origin. During mid 2004, the Ministry of Defense (MoD) approved the induction of a new generation of MCMVs. The MCMVs were to have high-resolution sonar for detecting mines and then neutralise them with remote-controlled mine disposal systems. The ships were to have lower acoustic and magnetic signatures and improved resistance to underwater explosions. The plan was to have eight MCMVs to be constructed by Goa Shipyard Limited (GSL), which had been modernised for this purpose. The acquisition went through many twists and turns when the RFP for construction and technology assistance was sent to many companies. The Defence Acquisition Committee had cleared nomination of GSL for construction of 12 MCMV vessels in February 2015 in collaboration with South Korea’s Kangnam Corporation. During January 8, 2018, the Indian Government cancelled the tender due to differences in pricing and mode of transfer of technology. It is understood that the acquisition process will start again with the invite sent to Kangnam Corporation, Intermarine of Italy, Navantia of Spain, Lockheed Martin of US, ThyssenKrupp of Germany and Russian shipyards. It appears that the ‘Make in India’ for defence is floundering due to high cost of transfer of technology by foreign OEMs. It is hoped that the issue is resolved and this important operational void is soon made up.