Mines have a long history of reshaping naval warfare, both by damaging individual ships and by countering the actions of entire fleets. Remarkably, though, one way to make them even more effective is to take a “back to the future” approach in which vintage mine technologies, even some dating a century or more, are employed alongside modern capabilities.
Even relatively unsophisticated mines have been used to prevent ship movements from Vietnam to the English Channel, while also thwarting amphibious assaults from the gates of Istanbul to the coasts of Korea. From 1988 through 1991, mines damaged three U.S. warships and many civilian ones in the Persian Gulf.
Most recently, Ukraine has used naval mines to help invasion of Odesa. Mines can help to negate the superior power of enemy fleets not only by directly damaging their ships, but by inducing them to avoid key waters or to engage in mine-countermeasures efforts that delay and disrupt their plans. For example, naval mines could help to stymie a potential Chinese invasion of Taiwan, hindering China’s ability to rapidly deliver a massive force ashore. In locations across the globe, naval mines could also be used to trap hostile submarines in port. They can also be used to impose “sanctions with a bite” by precluding an aggressor from using specific waterways until certain conditions are met.
The U.S. military is working to develop its currently vestigial naval mining capabilities. It has a handful of air-dropped bottom influence mines, which sit on the seafloor and detonate when they sense a ship’s characteristic sounds or magnetism overhead. The U.S. is working on mines that can be delivered clandestinely or can be released from aircraft at long ranges from the target area. In addition, the U.S. is developing mines that can launch torpedoes when they detect a ship’s presence, a capability that it first developed towards the end of the Cold War.
Burnishing capabilities from the 1980s, though, could be only the beginning. A very effective way of complementing today’s advanced mines is by employing mine technology that dates back a century or even more. Moored contact mines that detonate on impact, like the “spiky balls” used in World War I, require different modalities of mine countermeasures (MCM) from bottom influence mines. Sonar searches for moored and bottom mines have to be conducted sequentially, while moored contact mines are immune to ship emulating MCM gear that attempts to prematurely detonate influence mines.
For the U.S., scattering a few moored contact mines among a larger number of bottom influence mines would require additional MCM efforts to counteract both, protracting clearance timelines. If an adversary did not undertake MCM against moored contact mines, because it was not aware of their usage, it would likely lose ships and then have to belatedly address that secondary threat. Throughout these protracted and perhaps confused MCM operations, MCM forces and other ships would be vulnerable to U.S. targeting.
Similarly, old-fashioned drifting mines can be tremendously disruptive to an adversary’s fleet actions or its MCM efforts against fixed mines. Under international law, drifting mines must neutralize themselves within one hour of release. However, under the right circumstances, they can do a lot of mischief within that single hour. Slightly submerged drifting mines could be released from uncrewed undersea vehicles or low-visibility uncrewed surface vehicles just up current from a fleet or from MCM forces tackling a fixed minefield.
The technology involved is very old: the U.S. first used drifting mines that detonate on contact in 1777. Drifting mines could help to disrupt a fleet as it was trying to maintain formation or adhering to channels where MCM had previously been conducted. Available tactics against drifting mines are mostly risible, consisting of having people try to spot incoming mines, then trying to avoid and/or shoot them. The result is that ships would be continually damaged by an invisible threat, with no meaningful capacity to counter it.
A third approach is to use remotely controlled mines that have a hard-wired connection to a facility on land. Controllers at that facility can decide whether to detonate a mine when a ship approaches one of them or could simply activate (or de-activate) a set of influence mines that respond to ship signatures. Again, the U.S. has been here before: at the turn of the 20th century it protected ports with remotely controlled minefields. Today, coastal nations such as Taiwan and the Baltic states could employ such minefields to better protect their shores from hostile fleets. Having numerous, distributed links between individual mines and various shore locations can reduce vulnerability to both the severing of cables and the targeting of the control facilities themselves. Remotely controlled mines are relatively impervious to typical MCM tactics, while any MCM assets would be highly vulnerable to various shore-based defenses.
Overall, while naval mine warfare benefits from technological development, employing a few old-style mines can be a useful complement to modern capabilities. The low costs associated with naval mines may be further reduced by constructing some with century-old technology. Some other nations already use seemingly antiquated mines: Russia’s M08 moored contact mine is named for the year of its development—1908. By using moored contact, drifting, or remotely controlled naval mines in combination with advanced counterparts, the U.S. and other nations can inexpensively help to counter prospective aggressors as part of a range of naval defenses.
Dr. Scott Savitz is a Senior Engineer at the nonprofit, nonpartisan RAND Corporation.
