Discover the Riverine Command Boat (RCB-X)

An Experimental Military Boat

Riverine Command Boat (Experimental)
Riverine Command Boat (Experimental). Photo courtesy U.S. Navy

The Riverine Command Boat (Experimental) (RCB-X) is an experimental military craft that is testing alternative fuel blends. RCB-X uses a blended fuel consisting of 50 percent algae-based biofuel and 50 percent NATO F-76 fuel. The goal is to reduce the Navy’s consumption of petroleum-based fuels. RCB-X is an experimental version of the Swedish Riverine Command Boat. Over 225 Riverine Command Boat’s are in use worldwide.

Riverine Boat Specs

Riverine Command Boat (Experimental) (RCB-X) is a 49-foot long, 12-foot wide craft that is fast and agile. The vessel is designed for use on rivers for patrols and assaults by small forces. The RCB-X has a top speed of 44 knots, 1,700 horsepower and a crew of four. It also has a 3-foot draft allowing for easy travel on most rivers. It has Swedish built engines and Rolls Royce twin-ducted water jet propulsion. The bow is reinforced allowing the craft to be run onto shore at full speed without damage. RCB has a range of 240 nautical miles on rivers or open water.

There are six gun mounts on the vessel. One on the bow and another behind the mast are remote- controlled from the cockpit. The other four are used for manned weapons. It can carry .50 caliber machine guns, mortar, 40 mm grenade launchers or Hellfire missiles. The mortar launcher is a twin-barrel 12 cm. mortar. RCB can carry up to 20 troops at one time, and be transformed into a dive support vessel or a command craft. The boat can also be configured as an ambulance to take wounded soldiers off the battlefield by river. Made of heavy-duty aluminum, it has a 580-gallon fuel tank that contains a large, high-speed fuel fill capability. The bow drops down making it easy to disembark and return to the craft quickly. The cockpit is armor plated for protection and the cabin can be sealed against nuclear, chemical and biological agents. Over 4 tons of cargo can be carried on the craft.

RCB-X and RCB’s are built by Safeboat International under license from the Swedish company Dockstavarvet. The first models cost anywhere from $2 to $3 million each.

Bio Fuel

Because the Riverine boat is a test version for fuels, it garners power from a 50 percent algae-based and 50 percent NATO fuel called hydro-processed renewable diesel or HR-D. If the RCB-X used 100 percent biofuel, it would contain water which fouls the engines of Navy craft. Biofuels also have a six-month service life and the blend allows for longer term storage of fuel.

The biofuel blend is made by a company called Solazyme, which calls the fuel Soladiesel. Soladiesel is designed to be used directly in place of conventional fuels, with no modifications to the engines or fuel system of the craft. In 2010 Solazyme delivered 80,000 liters of Soladiesel to the U.S. Navy and was under contract for an additional 550,000 liters at the time of publication. The fuel is produced in partnership with Chevron and Honeywell in Illinois. Solazyme also makes a replacement for jet fuel and standard diesel vehicles. Solazyme’s algae grows in the dark using sugars from plants such as sugar cane and corn. Their system uses standard, industrial fermenters allowing for rapid scaling of production. Solazyme is based in San Francisco, California.


The Navy began testing the Riverine boat in 2010. It planned to deploy a strike group for local operations using the blended fuel in 2012 with full deployment in 2016. The Navy is testing the RCB-X, and it may be a possible fast craft for going from brown water (river) to green/blue water (ocean).