The U.S. Navy is having serious problems getting new naval mine hunting technology to work. The major problems are with two components of the RMS (Remote Minehunting System) device that is meant to provide the new LCS (frigate sized) ships with the ability to detect and eliminate naval mines. This system has two major components. The simplest one (technically) is the RMMV (Remote Multi-Mission Vehicle) a 7.5 ton remotely controlled submarine that carries the gear that actually finds the mines. The most troublesome of these items are the various electronic components. Because of that RMS fails on average every 18 hours of use. The RMMV alone fails every 25 hours but appears easier to get fixed. So far eleven RMS systems have been built but the navy needs many more and cannot justify ordering them (at about $31 million each) until the reliability is improved.
Getting RMS working effectively is a big deal. Since the late 1990s the United States Navy and many of its allies have devoted a lot of attention and cash to one of their greatest dangers; naval mines. The more dangerous bottom mines (which lie on the bottom of shallow coastal waters) require different tools to find and destroy than the older mines that lurk just beneath the surface However, many areas along the coast are too deep for the bottom mines (which are ineffective in waters more than 26 meters/80 feet deep).
As a result there has been a major change in how to deal with this problem. Instead of the old system, where a small force of mine clearing ships and helicopters were kept in readiness at a few bases, new mine clearing equipment will be on warships at all times. Currently it can take days or weeks to get mine clearing equipment to ships overseas that need it. In addition, the United States is replacing its two dozen mine hunter ships with LCS (Littoral Combat Ships) carrying mine hunting and clearing equipment.
To create this new approach required some most radical innovations so that there was portable mine hunting gear that any warship can carry and use. The key technology here is the use of miniature, unmanned, submarines. These UUVs (unmanned Undersea Vehicles) come in many sizes and models. One of these new mine hunting systems, the RMS, was developed during the 1990s and has been entering service with U.S. ships from the late 1990s on. RMS is a miniature robotic submarine (7.4 meters/23 feet long, 1.1 meter/four feet in diameter) that runs just below the surface, with only a mast (for getting air to the RMS's diesel engine and to hold radio antennas and a video cam that looks out for obstacles on the surface) above the waterline. The front of the RMS holds a sonar that helps with navigation by looking for underwater obstacles. RMS tows an AQS-20 variable depth (it can change its depth to get better coverage) sonar. This system maps an area, showing where objects that might be mines are. RMS carries enough fuel for 24 hours of operations at a speed of about 20 kilometers an hour. RMS can be set to survey an area and return to the ship that launched it. A controller on the ship can give RMS specific navigation commands or change earlier ones. In many cases the RMS survey will show areas free of any suspected mines and this allows friendly ships to go where they want to. The AQS-20 has been upgraded to include an underwater camera that will broadcast back to the ship high resolution images of underwater objects.
Most of these items are complex technology that was only recently developed. Because of that a lot of problems are expected. But these new systems are expected to replace an older, less capable but more reliable system that is rapidly being retired in the U.S. Navy.