Surface Forces: Mines Revisited


March 13, 2020: Russia is finally getting its new Project 12701 Alexandrite-E class MCM (mine countermeasures) ships into service. Construction began on the first ship in 2011 and was to enter service by 2015. That was delayed a year because of the 2014 sanctions (in response to the Russian attack on Ukraine) prevented the importation of some crucial components. As of early 2020, four of the new MCMs are in service and three more are under construction. The navy wants forty of these vessels to protect ports, and especially naval bases, from naval mines. While mines are expected in wartime there is also the risk of Islamic terrorists getting their hands on them and using them right now. Iran and pre-2003-Iraq have tried to use these weapons clandestinely in peacetime but this was not a widespread practice. However, the threat remains. Nations that are not prepared to cope will see their seaborne commerce disrupted along with their economy in general. A lot of nations are currently in need of help here.

The Alexandrite class ships displace 890 tons and have a fiberglass hull as protection against magnetic mines that detect metal ships. These new mine hunters have a max speed of 31 kilometers an hour but when working, and searching, move much more slowly. The ships have a max endurance of ten days and a crew of 45. Armament consists of one multi-barrel 30mm autocannon, shoulder-fired anti-aircraft missiles, machine-guns and small arms for some of the crew. Mine clearing equipment consists of sensors and USVs (unmanned surface vessel) operated remotely to get a closer look at bottom mines and then smaller UUVs ((unmanned underwater vessel) for planting explosives to destroy bottom mines. There are flail systems to clear and detonate surface mines.

One reason Russian built these new MCMs is that there is an active export market for MCMs. India is a prospective export customer because currently India only a few operational but elderly MCM ships. At the same time, India is buying Australian mine-detection systems that can be mounted on any ship to detect mines. Western nations are also using such systems on helicopters as well as ships. The MCM solution most popular in the West is USV/UUV systems that can be used from any warship or from shore in a threatened port. The USV/UUV gear can be flown in quickly since a closed port is a disaster that gets worse the longer the mines have it shut down.

USV/UUV equipment has greatly improved since the 1990s. For example in 2017 an Israeli firm demonstrated its new Seagull USV system carrying out MCM missions (finding and destroying bottom mines) off the Belgium coast in rough weather. Seagull is designed to operate in Sea State 5 (six meter waves and 38 kilometer an hour winds) conditions and survive Sea State 7 (nine meter waves and 59 kilometers an hour winds).

Each Seagull system consists of two Seagulls and a base station operated from shore or on a ship for the three people needed to operate Seagull and its sensors and explosives. One Seagull carries several types of sensors (sonars and others) while the other Seagull carries a minisub for getting a closer look at bottom mines, or wire-guided torpedoes for destroying subs or bottom mines. Each Seagull USV is 12 meters (39 feet) long, has a top speed of 57 kilometers an hour, a payload of 2.5 tons and can stay at sea for up to four days at a time. The Seagull USVs can operate up to a hundred kilometers from base stations. Each Seagull system costs $30 million but can do the work of a manned MCM (mine countermeasures) costing three times as much or, when it comes to ASW (anti-submarine warfare) operations, frigate or corvette costing ten times as much. Seagull is a lot cheaper to maintain and operate and puts far fewer personnel at risk.

Seagull is not a radical new concept but rather the result of decades of unmanned aerial, land and naval vehicle development. The Israelis have been in the lead in most categories. For example in 2013 an Israeli firm presented a larger (11 meter/34 foot) version of the older nine meter Protector USV. This one was armed with a water cannon and Spike missiles. The 2013 model was more stable in rough seas and can stay out for over 12 hours at a time.

Ever since the end of the Cold War a growing number of naval officers and civilian experts have been urging that more attention be paid to dealing with naval mines. These warnings had an impact. For example in 2012 over 30 other nations conducted a joint mine clearing exercise in the Persian Gulf. Numerous separate events were directed at dealing with Iranian attempts to block the entrance (Straits of Hormuz) to the Persian Gulf. The impact of that exercise led to others held annually ever since. While Iran is the most immediate naval mining threat, they are not alone. North Korea, China and Russia much larger naval mine stockpiles, but these three are not boasting of how and when they would use them,

Iran insists that because of its mines and other weapons it will have no trouble blocking the export of oil via the Straits of Hormuz. Some 35 percent of the world's oil shipments pass through these straits, which comes to about 15-20 tankers a day (plus a dozen or more non-tankers). The Persian Gulf, in general, is a busy waterway. It is 989 kilometers long and the average depth is 50 meters (maximum depth is 90 meters). Naval mines are Iran's best bet if they want to shut down the straits. The Iranian problem is that they have a small navy, an obsolete air force, and a poor track record when it comes to shutting down tanker traffic in the Persian Gulf or the Straits of Hormuz. They tried once before, in the 1980s, when they were at war with Iraq. Iran quickly discovered that laying mines in wartime was difficult because the enemy was actively trying to prevent that. So Iran and Iraq began attacking each other's tanker traffic early on with other weapons, in an attempt to cut off each other's oil sales (and, thus, military purchases). Iran didn't want to shut the Straits of Hormuz because it needed the oil revenue more than Iraq, which was getting billions in aid from other Arab states. So each country concentrated on attacking shipping in the Persian Gulf. Over 500 ships were attacked, 61 percent of them tankers. Only 23 percent of the tankers attacked (mainly with anti-ship missiles) were sunk or immobilized. The attacks, using fighter-bombers and warships, only hit about two percent of the ship traffic in the Gulf. Iran lowered its oil prices to cover the higher cost of ship insurance and, in 1986, Russia and the United States intervened to protect Kuwaiti and Iraqi tankers (which were taking most of the damage).

The Iranian military is in worse shape today than it was in the 1980s and would not last long trying to attack ships with mines. That leaves the Straits of Hormuz. This is actually a wide (about 30 kilometers) deep channel. Normally, shipping sticks to narrow (a few kilometers wide) channels, going in and out, to avoid collisions. The main Iranian threat has always been seen as naval mines because the one place where Iran has a good chance of planting a lot of mines is the Straits of Hormuz.

The Arab states have a lot of mine clearing equipment and more numerous air and naval forces than Iran. In addition, there are the United States and NATO forces in the area. The problem was that all these mine clearing forces had not, until 2012 practiced under realistic (wartime) conditions. In short, it has long been unclear exactly what it would take to deal with Iranian mines in the straits. Many of those questions were finally answered in 2012 and during subsequent mine clearing exercises.

For an Iranian mining attempt to work they would have to get the mines onto the bottom of the straits and then prevent the rest of the world from clearing those mines. That would be difficult, as would Iranian attempts to plant additional mines. Such attempts would not be impossible as Iran has small submarines and speed boats along with sailors willing to carry out suicidal missions to deliver the mines. Even that may not be sufficient, as this sort of fanaticism failed against the Americans in the 1980s. While Iran has worked to overcome its shortcomings, most of the solutions appear to be publicity stunts mainly meant to make the Iranian population feel better.

Iran has a few thousand naval mines and that is a small arsenal compared to Russia (over 200,000), China (over 100,000) and North Korea (over 50,000). It is generally agreed that all these mines are a serious danger. While often ignored, naval mines are a formidable weapon. But these passive weapons just don't get any respect. The historical record indicates otherwise.

Modern naval mines were widely used for the first time over a century ago, during the Russo-Japanese war (1904- 1905). These were contact mines, floating in shallow water and kept in place with an anchor and chain. When the tide was right they would be just below the surface, ready to explode whenever struck by a ship. Some 2,000 of these mines were used to destroy sixteen ships during the Russo-Japanese war. That's one ship lost for every 125 mines used.

During World War I (1914-18), modern mine tactics and clearing methods evolved. Thousands of mines were laid to provide defensive barriers against enemy movement in the North Sea. Mines were also used offensively by secretly placing them across known enemy sea routes. More than 1,000 merchant and warships were lost because of the 230,000 mines used. That's over 200 mines used for every ship lost.

During World War II there was a major effort to develop better mine clearing methods to deal with an even larger number of mines. During World War II 2,665 ships were lost or damaged by 100,000 offensive mines. That's one ship for every 37 mines. Some 208,000 mines were used defensively to inhibit enemy movement and tie up his resources.

Naval mines achieved several striking successes during World War II. In the Pacific naval mines proved more destructive to the Japanese war effort than the atom bombs. During a 10 week period in 1945, 12,000 mines were placed off the Japanese coast by American bombers. These destroyed 1,250,000 tons of Japanese shipping (670 ships hit, 431 destroyed). That's 18 mines for each ship hit. The Americans had air superiority, so losses during these 1,500 missions amounted to only 15 planes, most of them accidents. Had these missions been flown against the opposition, losses would have been between 30 and 60 aircraft, plus similar losses to their fighter escorts. Either way, it was a stunning success for naval mines,

A conventional submarine campaign was also waged against Japanese shipping using mines. Comparisons between subs using mines and torpedoes are interesting. A hundred submarines were involved in a campaign that ran for 45 months from December, 1941 to August, 1945. Some 4.8 million tons of enemy shipping was sunk with torpedoes. For every US submarine sailor lost using submarine launched torpedoes, 560 tons of enemy ships were sunk. During the mine campaign, 3,500 tons were sunk for each U.S. fatality. On a cost basis, the difference was equally stark. Counting the cost of lost mine laying aircraft (B- 29's at $500,000 each) or torpedo armed submarine ($5 million each), we find that each ton of sunk shipping cost six dollars when using mines and fifty-five dollars when using submarines. This data was classified as secret until the 1970s. It indicates that mines might have been more effective than torpedoes, even if the mines were delivered by submarine.

The Germans waged a minelaying campaign off the east coast of the United States between 1942 and 1944. Only 317 mines were used, which sank or damaged 11 ships. This was a ratio of 29 mines used for each ship hit. More importantly, eight major ports were closed for a total of 40 days. One port, Charleston, South Carolina, was closed for 16 days, tying up not only merchant shipping but the thousands of men, warships, and aircraft dealing with the situation. American submarines also waged a limited mine campaign in the Pacific. For 658 mines used, 54 ships were sunk or damaged (12 mines per ship). No subs were lost. Considerable Japanese resources were tied up dealing with the mines. On the Palau atoll, the port was closed by the mines and not reopened until the war ended. Even surface ships were used to lay mines. Three thousand mines were laid by destroyers. Only 12 ships were hit but these were barrier fields, not the ambush type mine fields that a submarine can create by sneaking into an enemy held area.

In Korea during the early 1950s, the Soviets provided North Korea with 3,000 mines, many of 1904 vintage. These were used to defend Wonson harbor. It took several weeks for UN forces to clear these, at a loss of a dozen ships hit. Half of these ships were destroyed.

During the Vietnam War over 300,000 American naval mines were used, primarily in rivers. The vast majority were not built as mines but were aerial bombs equipped with magnetic sensors instead of fuzes. These bombs/mines used a small parachute to ensure that no damage occurred on landing. In shallow water, these makeshift weapons sat on the bottom and performed as well as mines until a timing system deactivated the or the battery was exhausted. While modern bottom mines have long-lasting batteries, there is still a limit (several years) that they can remain active.

In 1972 Haiphong Harbor was mined with 11,000 of these "destructors," as the US air force called them, and less than a hundred conventional mines. Haiphong Harbor was shut down completely for months, and it took years to clear out all the American mines. The "destructor" mine design was so successful that it is still in use, using more modern electronics and batteries, as the Mk 62 mine.

During the 1991 Gulf War, the Iraqis laid over a thousand mines off the Iraqi and Kuwaiti coast. The predominantly US naval forces did not have sufficient mine sweeping resources to deal with this situation and had a helicopter carrier and cruiser hit and damaged while trying to clear the area. This effectively prevented any US amphibious operations, although the Marines were not going to be used for a landing anyway. It took over a month of mine clearing after the fighting ceased to eliminate all the mines. In the meantime, two U.S. warships were damaged by these mines. In 2003, the Iraqis again tried to use mines but were hampered by prompt American, British, and Kuwaiti action.

In any future war, naval mines will again surprise everyone with how effective they are. It is feared that terrorists might get their hands on some bottom mines, but so far, there do not appear to have been any attempts.

The U.S. Navy has systems similar to the Israeli Seagull and has many helicopters equipped for mine clearing. But the navy is having a very difficult time maintaining its force of MH-53E helicopters. These aircraft are the only ones that can tow a sled containing naval mine detecting gear. This sort of thing is called AMCM (Airborne Mine Countermeasures) and is considered essential in areas, like the Persian Gulf, where the enemy (Iran) might use a lot of naval mines that would have to be cleared quickly in wartime.

The MH-53E is an update of the original 1960s era CH-53 and entered service in the early 1980s. Fifty MH-53Es were built and they have been worked hard ever since. That’s why only 30 are left and few of them are fit to fly at any one time. Originally the navy planned to retire the MH-53Es in 2008, but replacements (lighter sleds that could be pulled by smaller and more modern helicopters) did not work out as expected. So retirement was pushed to 2012, then 2017 and currently the navy hopes to keep some MH-53Es operational into the 2020s.

Meanwhile, efforts continue to develop lighter equipment for the mine hunting task. Some of these projects have had limited success. The AQS-24A mine-hunting system looks like a torpedo with extra fins and attachment. It is lowered into the water and dragged by the helicopter at speeds of up to 34 kilometers an hour. The AQS-24A contains a high-resolution sonar that seeks out mines that lie on the sea bottom, waiting for ships to pass over. The bottom mine then detonates if a ship type it was programmed to attack is detected. The U.S. Navy has been using this mine hunting approach since the 1980s. The original sled system went through several major upgrades and is considered very reliable and effective. The MH-53E sled can carry more equipment and sweep a larger area faster.

The U.S. Navy has also developed a complementary system, ALMDS (Airborne Laser Mine Detection System). Designed to operate from the MH-60S helicopter, ALMDS uses a Laser Imaging Detection and Ranging blue-green laser to detect, and identify naval mines near the surface. Unlike the AQS-24A, ALMDS operates from the low flying, and smaller, helicopters. Surface mines are either moored (via a chain to the bottom) or floating (a favorite terrorist tactic), and many float just below the surface. The laser works very quickly and enables the ALMDS equipped helicopter to quickly check out large areas for surface mines. Terrorists have used naval mines before, of the floating variety. Navies tend to use the more sophisticated, expensive and hard-to-get bottom mines (that lie on the bottom, in shallow water).

American allies have also developed new mine detection and clearing tools and some of the new U.S. equipment uses foreign tech. While new mine designs have become more effective, the basic problem is that the many older mine designs are still very dangerous, especially for the unprepared.




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