U.S. intelligence officials have assessed that Iranian forces have deployed a small number of mines in the Strait of Hormuz, a critical choke point for global shipping, according to reports. The move gives the Iranians a means, along with missiles and drones, of threatening ships.
The U.S. Navy recently decommissioned the minesweeping vessels that it had operating in the Persian Gulf region. However, it has other ships and aircraft for finding and destroying mines.
As a computer scientist who researches how to detect mines, I have been researching how artificial intelligence techniques, such as machine learning, can help navies detect modern sea mines. Here’s what I’ve learned about how the mines work and how they can be neutralized.
Types of mines
The mines most people picture, like those seen in films such as “Godzilla Minus One,” are floating spheres tethered to the seabed, with small protrusions called Hertz horns that trigger the mine when it makes contact with a ship. These are called moored mines.
In the film, characters use a small wooden boat to sweep mines without triggering them because the mines responded to a metal-hulled ship’s magnetic field. Detecting magnetic fields is characteristic of influence mines, which respond to a ship’s magnetic, acoustic or pressure signature, as opposed to simple contact mines that detonate when ships run into them.
Modern mines typically combine multiple sensing modes. Some are designed to detonate only after a certain number of ships have passed, allowing them to ignore smaller vessels or minesweeping attempts and target higher-value ships. Examples include the Iranian Maham 3, which uses both magnetic and acoustic sensors.
Not all mines float. Many modern mines instead sit on the seabed. These mines are most effective in shallow water, where ships pass closer to the seabed. Some bottom mines sit exposed on the seabed, while others are partially or completely buried in sediment. Examples include the Iranian Maham 7 and the Manta mine, a low-profile bottom mine used by Iraq during the 1991 Gulf War. These mines can be deployed by small vessels or laid from aircraft, making them relatively easy to place. They are triggered when they sense a ship passing overhead.
This is an example of a ‘Manta’ naval mine.
U.S. Naval Forces Central Command/U.S. Fifth Fleet on Flikr, CC BY
Many modern mines are cylindrical or torpedo-shaped, allowing them to be deployed from aircraft or submarines and descend in a controlled way before settling on the seabed. More advanced designs include so-called rising mines, which sit on the seabed and launch upward toward a target once it is detected.
Mine countermeasures
A key advantage of naval mines is not just the damage they can cause, but also the time and resources required to find and clear them. This is because it’s challenging to do so over large areas quickly and reliably.
Even the…
