January 7, 2024: Over a decade ago the U.S. Navy developed a new Unmanned Surface Vessel or USV, called the Blackfish. It was designed from scratch as a USV, not just the usual practice of taking existing small boats and adapting them for remote and autonomous control. The Blackfish was 3.2 meters long, looked like a large, unmanned jet ski, and was equipped with video cameras, sonar, and some other sensors. Using GPS, it can automatically patrol a predefined route, or be controlled remotely. What the navy wanted was an inexpensive USV for patrolling port areas where American ships are tied up, and so had to be able to detect divers, as well as small boats. That sort of work was eventually replaced by oceanographic research, and environmental monitoring.

The U.S. Navy earlier developed the AMN 1, which is a flat-bottomed USV for operating in shallow coastal waters and up rivers. For riverine operations, the navy has had to develop navigation software for tricky situations, like having the radar (in this case, laser-based lidar) be able to detect a bridge as something it can go under, and not an obstacle to further movement. AMN 1 is equipped with most of the equipment that current USVs have been successful with.

Some USVs, like the Israeli Protector and the American Spartan Scout, are already being used to patrol coastal and port areas like the Gaza coast, and the waters around the Lebanese border. These USVs are basically 4-8 ton, 11 meter speed boats equipped with radar, GPS and vidcams, and armed with a remote control 12.7mm machine-gun using night vision and a laser rangefinder. There is also a public address system, to give orders to boats that should not be there. These USVs have been used for two decades. They can be controlled from an operator ashore, or in a nearby ship, usually out to the horizon or at least 10-20 kilometers distant. They can stay out 8-48 hours at a time, depending on how much high speed movement is used. The one big shortcoming is that most USVs are built for speed, not rough seas. When the weather turns bad, and the waves get higher, they have to be brought in.

Spartan Scout was particularly useful when it got its first tryout in the Persian Gulf during late 2003. There are lots of small boats moving about, some of them up to no good. An Arab linguist on the mother ship was able to interrogate suspicious boats the Spartan Scout ran down. The civilian sailors were somewhat taken aback when they were interrogated by this Arab speaking boat that had no one aboard. While Spartan Scout was developed primarily to work with the now retired Littoral Combat Ship, most similar ships, like frigates and destroyers would like to have one just for port security.

The U.S. Navy has also developed a new anti-submarine USV (unmanned surface vessel) to operate from its LCS (Littoral Combat Ships). Officially called the 11-meter Fleet class Anti-Submarine Warfare Unmanned Surface Vehicle (ASWUSV), the 12.6 meter long boats weigh 8.5 tons and can carry 2.5 tons of sensors and other equipment. This USV can move up to 63 kilometers an hour and stay at sea for up to 24 hours. Most of the time, it would be moving slowly, using its sonar to search for subs. The ASWUSV is equipped with GPS and a computerized navigation system that allows it to automatically run search patterns. Thus, the sailors controlling the boat remotely can move it to an area where helicopter or aircraft dropped sonobuoys have picked up a contact and pursue it more intensively with the more powerful sensors it has on board. Such pattern searching, worked out with algorithms derived from experience with what subs can do, has been a successful tactic since World War II.

While ASWUSVs can be used by frigates and destroyers, they can also be used from shore stations. Some were apparently tested in the Persian Gulf, to help keep the Straits of Hormuz free of Iranian submarines. The ASWUSV also carries video cameras and radar, to assist in avoiding collisions with other ships, and to keep Iranian gunboats from capturing or damaging one. The ASWUSV was developed based on experience with the Spartan Scout, while the AMN 1 is building on that experience and developing new design features for the next generation of USVs. South Korea is the latest nation to develop and user an ASWUSV.