Submarines: The Long Arm Of The Hidden Threat


October 20, 2018: In September 2018 the U.S. successfully used a JDAM glide and satellite navigation kit to deliver a 2,000 pound (909 kg) Quickstrike naval mine to a location over sixty kilometers from where the B-52 bomber was. This Quickstrike had no explosives, just inert material to maintain the proper weight. The Quickstrike had its naval mine sensors and other electronics plus a locator device. That enabled a ship to locate and recover the Quickstrike, which was found to be functioning properly. These tests began in 2015, using a 500 pound (228 kg) Quickstrike and later a 1,000 pound (456 kg) Quickstrike. Now the Air Force or Navy can deliver all three sizes of these Quickstrike ER (extended range) mines using JDAM. In addition to GPS JDAM also has an unjammable (but somewhat less accurate) INS (inertial guidance system). This less accurate INS is precise enough for Quickstrike.

The original Mk-62 Quickstrike was basically a 500 pound bomb, with a sensor package attached to the rear. There were three different sensor packages, each providing a different set of sensors to detonate the mine. The Mk-62 is a "bottom mine," which is dropped in shallow water, and then detects a ship passing above using pressure (of the ship on the water), magnetism (of the metal in the ships hull), or vibration. The sensor also comes with a computer, to enable the mine to follow certain instructions (like only detonate for ships that meet a certain criteria.) Think of Quickstrike as the ultimate underwater weapon, being relatively inexpensive, autonomous relentless in carrying out its’ mission.

One drawback with the Quickstrike is that the aircraft delivering it had to drop the mines at an altitude of 300 meters or less while moving at 500-600 kilometers an hour. The mines are usually dropped in known shipping lanes, especially those that serve as approaches to a major port. During World War II, air dropped mines proved devastating to Japanese shipping. Same thing with their use against North Vietnam during the Vietnam War. Any bomber aircraft that can go in low and slow can deliver Quickstrike. Thus the F-35, F-18, B-2, B-1B, P-8 and P-3C can also deliver naval mines. The U.S. air force and navy revived regular Quickstrike bombing exercises over a decade ago and publicized them to send a message to North Korea, Iran and China about how quickly their seaborne lifelines could be cut. China responded by stationing air defense systems to cover the shallow water sea lanes that Quickstrike could be used in.

The United States responded with Quickstrike ER. The current JDAM smart bomb kit comes with wings that enable the bomb to glide up to 70 kilometers thus avoiding many enemy air defenses. It also means you don’t have to risk your nuclear subs for the delivery of these mines. Subs have long been an effective way to plant mines in enemy waters. The JDAM approach does not eliminate all risk from anti-aircraft systems. China and Russia have modern S-300 systems with ranges of over 200 kilometers. But the farther away the attacking aircraft are the less they are at risk. That’s because American aircraft go into combat with EW (electronic warfare aircraft) and EW devices on all aircraft. That provides a lot of protection but it is not 100 percent and the less time you spend in the danger zone the less risk you are exposed to.

There more improvements planned for Quickstrike. The next step is to test longer range glide bombs like JASSM, with a range of up to 900 kilometers. The original JDAM bomb kit (added to 500, 1,000 and 2,000 pound bombs), cost $26,000 each. The longer range (120 kilometers) JSOW (JDAM with larger wings and more powerful guidance system), cost $460,000 each. The even longer range JASSM cost $500,000 (the 400 kilometers version) to $930,000 (the 900 kilometer JASSM ER) each. Air defense systems can detect JDAM, JSOW and JASSM but with some difficulty because these glide bombs are small, low and slow moving.

Meanwhile, the United States and its allies have to spend a lot more effort figuring out how to effectively deal with enemy naval mines. The few enemies the West has posses a lot of these mines. 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 it should be 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. That was a need because during this long (1939-45) war a total of 2,665 ships were lost or damaged to 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 between April and August 1945, 12,000 mines were delivered to 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 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 U.S. 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 minefields 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 on the west coast of North Korea. 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 North Vietnamese 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 insure that no damage occurred on landing. In shallow water these makeshift weapons sat on the bottom and performed as well as mines. Haiphong Harbor was actually 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, as the Mk 62 Quickstrike mine. Now there is the Quickstrike ER which is one of the mines delivered via JDAM.

During the 1991 Gulf War, the Iraqis laid over a thousand mines off the Iraqi and Kuwaiti coast. The predominantly American 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 U.S. 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.




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