October 25, 2024: Australian firm Anduril has built working prototypes of its three-ton autonomous submarine, called Ghost Shark. Prototypes have been tested at sea, using a partial complement of sensors required to make Ghost Shark operational. These prototypes were able to submerge and travel under water then surface so they could be recovered. Ghost Shark development began in 2021, based on previous research and work on autonomous submarines.

One previous autonomous submarine was Remus 100. This is a 37 kg vehicle that looks like a small torpedo. It is 1.6 meters long and 190mm in diameter. Carrying a side scanning sonar and other sensors, a Remus 100 can stay underwater for 22 hours, traveling at a cruising speed of five kilometers an hour with a top speed of nine kilometers an hour. The Remus can operate up to 100 kilometers from its operator, and dive to 100 meters. For guidance Remus uses GPS when surfaced and then nearly as accurate Inertial Guidance System/INS when submerged. Remus surfaces every hour or two to get a GPS fix, and then goes back to doing what it was programmed to do. Ukraine is using Remus to find and eliminate Russian bottom mines in shallow coastal waters.

The battery powered Remus 100 was designed mainly for civilian applications like inspecting underwater facilities, pollution monitoring, underwater survey or search. But there are similar military and police applications, like searching for naval mines. Australia and New Zealand also use Remus 100, and several hundred are in use. Depending on sensors carried, each Remus costs $350,ooo to $500,000.

Britain donated two Sundown class minehunters to Ukraine. These ships had several Seafox UUVs on board. Seafox is similar to Remus and used to detect and destroy naval mines, by placing explosive charges. Seafox weighs 43 kg and is 1.31 meters long and 390mm in diameter. There are many other variants of the basic Remus technology. Ghost Shark is one of them, just bigger, heavier and more capable. Ghost Shark, like Remus, can be equipped with different sensors and other accessories depending on the mission.

Ghost Shark is much larger than the battery powered Remus and Seafox. It was not revealed what energy source is. It could be an autonomous AIP system, which can be powered by Lithium ion batteries. Japan and South Korea have been using special Lithium ion batteries designed for use in submarines. AIP is even more efficient when used in an uncrewed submarine like Ghost Shark.

The U.S. Navy has ordered some Ghost Sharks and is testing them this year. The Americans want to see Ghost Shark design specifications finalized as soon as possible so that mass production can begin in the United States.