Robotic Submarines Prowl The Belgian Coast

The Belgian Navy recently bought two Remus 100 UUVs (Unmanned Underwater Vehicle) for use in finding naval mines placed on the seabed in shallow coastal waters. More frequently, however, the Belgians will be using Remus to find and dispose of unexploded munitions from the last two world wars. There's a lot of that stuff down there, which fishing boats often bring up, sometimes injuring fishermen in the process. 

The Remus 100 is a 37 kg (80 pound) vehicle that looks like a small torpedo (1.75 meters/5.4 feet long and 190mm in diameter). Carrying side scanning sonar, and other sensors, a Remus 100 can stay under water for 22 hours, traveling at a cruising speed of five kilometers an hour (top speed is nearly twice that). The UUV can operate up to 100 kilometers from its operator and dive to 100 meters/300 feet. The Remus keeps costs down by using GPS, in addition to inertial guidance. The UUV surfaces every hour or two to get a GPS fix, receive instructions, and transmit data and then goes back to doing what it was programmed to do. It's not uncommon for a Remus to get lost while doing its job and for those situations there is an emergency transponder.

Remus 100 was designed mainly for civilian applications (inspecting underwater facilities, pollution monitoring, underwater survey or search). But there are similar military and police applications, like searching for mines or other terrorist activities. The U.S. Navy uses Remus, as do many other nations. This is in addition to many tasks conceived by the many civilian users. Australia and New Zealand also use Remus 100 and over 200 are in use (about a third of all UUVs). Depending on sensors carried each Remus costs $250,000-500,000. The U.S. used Remus 100 in Iraq to search for naval mines.

There is also a larger version, Remus 600. This is a 240 kg (528 pound) vehicle that is 3.25 meters (10 feet) long and 320mm in diameter. Carrying side scanning sonar, and other sensors, a Remus 600 can stay under water for more than 24 hours, traveling at a cruising speed of 5.4 kilometers an hour (top speed is nearly twice that). The UUV can operate up to 100 kilometers from its operator and dive to 600 meters (1900 feet).