On 5 August 1864 at Mobile Bay, Admiral David Farragut gave his famous—albeit often misquoted—order: “Damn the torpedoes . . . Captain Drayton, go ahead!”1 Admiral Farragut’s bravado made him one of the Navy’s most renowned heroes. Yet, unknown to many, Admiral Farragut did not charge brashly into unknown waters. During the week before the assault. Lieutenant John Watson, Admiral Farragut’s aide, had led small boats into the bay under the cover of darkness to chart the positions of the mines.2 Perhaps then, the victor of New Orleans and Mobile Bay also deserves the title: the Father of Mine Countermeasures.
The technical sophistication of mines and mine countermeasures has increased dramatically since 1864. Today, mines can distinguish between warships, merchantmen, and submarines and can search actively for targets. Lieutenant Watson’s small boats have been superseded by minesweepers, minehunters, and mine-countermeasures ships equipped with sophisticated sonars and mine-neutralization vehicles.
Mines are deadly to all ships; however, to a submarine, they are especially threatening. Unlike a submarine’s other enemies—e.g., helicopters and other submarines— mines generally make no noise as they wait for a target. Some mines—e.g., the U.S. Mk 60 Captor—are torpedoes complete with active sonar tracking. This quality of mines strips submarines of their most effective defense—namely, the ability to hear danger before encountering it. However, just as technological advances have made mines more dangerous, they also might allow submarines to play an effective role in mine countermeasures.
To understand how submarines fit into the mine-countermeasures equation, one must first understand modem mines. There are three basic types of mines: floating, moored, and ground (or bottom) mines. Although “outlawed” by the Hague Convention of 1907, floating mines drift freely with currents and, therefore, pose little to no threat to a submerged submarine. Moored mines have two basic variants—contact and influence—and many subvariants, including mines designed to oscillate between depths. The ability to oscillate between depths, usually around a thermal layer, makes it more difficult for a submarine to avoid such mines. In the blue-water areas, however, the effectiveness of moored mines is questionable because of the vast space through which submarines actually can travel.
Considered by many to pose the greatest danger to submarines, ground mines have a wide variety of influence activation methods: acoustic, magnetic, pressure, and electric potential.3 Activation methods can be combined to provide a more specific set of criteria when defining a target; this capability also makes them harder to sweep and clear. Some mines have a special coating to reduce their sonar echo; others are designed to resemble debris—such as a refrigerator or discarded automobile—on sonar. Some modern ground mines can burrow into soft bottoms while maintaining their ability to detect, at a minimum, magnetic signatures.4 A ground mine covered by a quarter inch of sand is almost impossible to detect with sonar, and, in general, will be found only when a target attracts its attention. Contemporary ground | mines can be laid by submarines, surface ships, aircraft, small fishing vessels—just about anything that can carry mines.
Mines have wide variety of offensive and defensive uses in both littoral regions and the open ocean. They are effective in harbors, in coastal regions, and in the strategic chokepoints of the ocean.
Harbors are the key to maintaining both an economy and a navy. Without seaborne trade, a nation’s economy will come to a grinding halt. Additionally, a lack of ports to resupply naval vessels certainly will reduce a navy’s effectiveness. Ports also are essential in sustaining a military campaign; disrupting the flow of ships in and out of a port—or shutting it off altogether—is a surefire way to cripple an enemy.
From the perspective of defense, placing mines around the entrance to a harbor will prevent enemy ships—particularly submarines—from closing. Because the approaches to harbors are relatively shallow—usually less than 200 feet—ground mines will be the likely weapon of choice. Friendly ships will know the one safe path through the field; enemy ships, however, will be forced to risk the dangers of the mines to gain entrance. Mines are 24-hour sentries that don’t sleep, eat, and, with today’s technology, usually don’t miss an intruder. Consider also that the noise of one mine activating and seeking a target generally will trigger other nearby mines. Thus, these relatively inexpensive sentries can launch a very sophisticated saturation attack against an approaching enemy.
Mines also can provide a strong defense. Consider again the protected harbor with its one safe passage. A few well-placed ground mines would close that passage, sealing off the harbor until they could be swept. In an open harbor with no protection other than coastal defense ships, a submarine could lay mines within the harbor from four nautical miles away. The only thing a defender might hear would be the mine-housing units as they speed their mines to their destinations. In a very short time, an open harbor would be a death trap for merchant ships and warships alike.
In coastal regions, mines are an effective means of defense, especially if a country is confronted by a stronger naval power. During the Persian Gulf War, Iraqi mines were a great equalizer against the U.S. Navy.5 Iraqi ground mines effectively prevented a U.S. amphibious assault against Iraqi-occupied Kuwait, stopped Coalition naval forces from patrolling the northern Persian Gulf, and had a major impact on the ability of the USS Wisconsin (BB-64) and the USS Missouri (BB-63) to provide naval gunfire support. Mines also interfered with sealift, including U.S. military cargo bound for Saudi Arabia.
Consider that the two mines that damaged the USS Princeton (CG-59) and the USS Tripoli (LPH-10) probably cost Iraq a fraction of the millions of dollars that it took to repair those two ships and it is obvious why mines are so attractive to so many nations.
The third main use of mines is in open, deep water, more specifically, in deep-water chokepoints—e.g., the Strait of Gibraltar or the Greenland-Iceland-United Kingdom Gap. The correct use of mines in open water can be just as devastating to an enemy as mining his home ports. Consider the impact on the U.S. Navy in the Mediterranean Sea if the Strait of Gibraltar were closed because it had been sown with mines. What would the Russian submarine fleet do if “Red Route One,” the main passage from its homeports to the Atlantic Ocean, were rendered impassable?
It makes sense, therefore, that today’s submarine force should be proficient in mine countermeasures (MCM). However, an examination of the MCM capabilities of the silent service shows that mines now are quite possibly the most challenging opponent faced by submariners.
While most MCM tactics for submarines remain classified, some information regarding research on promising new MCM equipment—especially the sonars, drones, and lasers used to detect mines—has come to light.
Despite their aforementioned limitations, sonars remain the most efficient method of detecting mines. New submarines, such as the Seawolf (SSN-21), will be equipped with synthetic-aperture and ultrawide-band sonars. These active sonars, operating near the 100 kilohertz region, provide very sharp images at ranges up to 600 feet, while providing enough attenuation at ranges of more than 1,000 feet to be virtually undetectable by sonar-equipped ships.6 More important, because emissions are very rare at that frequency range, acoustically activated mines would not be triggered by the sonar. Therefore, a submarine would be able to generate high-resolution images of the ocean floor and remain relatively safe from any mines in the area.
Another recent innovation in mine countermeasures is the use of drones. GEC-Marconi is developing the Archerfish system, a self-propelled, remote-controlled disposal weapon that can be used to destroy both moored and ground mines. The Archerfish carries a low-light television camera in its nose and is controlled from its launching platform via a fiber-optic link. A shipboard operator would nose the drone up to a mine and then detonate a small shaped charge to destroy it. Although the Archerfish initially was conceived as a surface-launched weapon, researchers at GEC-Marconi are investigating its use by submarines as well. A submarine probably would not use the Archerfish to sweep an entire mine field; instead, it could clear a path into protected regions. The major drawbacks to deploying the Archerfish on submarines are finding a place for its control station and other related equipment and the fact that the weapons would occupy torpedo spaces in a submarine’s weapon-storage area.7
A third method of mine detection currently being investigated is laser-based sensors. These sensors use very focused beams— typically, less than six millimeters wide—with wavelengths in the blue-green region. One such system is the SM-2000 synchronous laser line-scanning system, developed by Westinghouse Corporation. The U.S. Navy already has tested this equipment, and has conducted several trials on board the USS Dolphin (AGSS-555). Laser line scanners “provide high-contrast, high-resolution images for route-survey and wide-area search operations at up to five times the range, even in turbid water, that can be achieved by other sensors.”8 Most important, lasers cannot trigger a mine.
Not many things are certain in naval warfare, but the Navy can be sure that it will encounter mines wherever it operates. Today, however, one of the most technically advanced portions of the Navy, its submarine force, is largely incapable of responding to this threat. Avoiding mined areas will ensure the safety of submarines from mines, but it also will ensure that submarines are excluded from the theater of action—neutralizing a large portion of U.S. naval strength. It is imperative, therefore, that the Navy continue to research and develop systems that will close the gap between mines and underwater MCM capabilities unless it is prepared to have billion-dollar ships sunk by thousand-dollar mines—and allow the submarine force to become irrelevant.
1. Roy Nafarette, ed., Reef Points, 1990–1991 Edition (Annapolis, MD: U.S. Naval Academy, 1990), p. 183.
2. Tamara M. Melia, “Damn the Torpedoes”: A Short History of U.S. Naval Mine Countermeasures, 1777–1991 (Washington, D.C.: Naval Historical Center, 1991), p. 3.
3. David K. Brown, “Damn the Mines!” U.S. Naval Institute Proceedings, March 1992, p. 46.
4. Brown, p. 46.
5. Ernest Fortin, “Those Damn Mines,” U.S. Naval Institute Proceedings, July 1992, p. 33.
6. John Boatman and Mark Hewish, “Naval Mine Countermeasures: Finding the Needle in the Haystack,” International Defense Review, July 1993, pp. 560–561.
7. Boatman and Hewish, p. 562.
8. Boatman and Hewish, p. 562.